Advances in Computer Science, Engineering & Applications

Wireless mesh architecture is a first step towards providing high-bandwidth network coverage. This architecture has major drawback of losing the bandwidth over multiple hops thereby resulting in poor quality of service (QoS) at nodes separated by more than two hops. This paper proposes a three step approach to guarantee bandwidth demand at each node of the network thereby providing high quality of service even to nodes separated by large distances from each other. The authors have presented a novel method for clustering the nodes and load sharing amongst the clusters based on graph partitioning approach. This work also presents a system and method of integrating Wireless Mesh Networks (WMN) with wired network for further increase in the QoS.

This paper describes a new secret key cryptosystem named CIPHER128 (C128). The algorithm is based on a feistel structure which encrypts a 128 bit block. It demonstrates few effective features like multiple S-Boxes, variable plain text size depending on data and key, padding by random variables, data and key dependent cyclic shift operations and variable length key.

In mobile ad hoc networks (MANET), achieving QoS guarantees by over-provisioning of the resources is typically infeasible because in these networks, the overall available bandwidth is quite limited. In this paper, we propose an optimal bandwidth allocation technique in IEEE 802.11e MANET. In this approach, initially available bandwidth is estimated using the bandwidth probing technique. The estimated available bandwidth is shared in reserved and shared region by the bandwidth sharing scheme for the real-time and non-real time flows respectively. The bandwidth allocation policy allocates additional bandwidth from the reserved region of available bandwidth, when the mobile host needs additional bandwidth for real-time flows. In case of excess bandwidth utilization of mobile hosts, the excess bandwidth is restored to the shared region of available bandwidth thus minimizing the reserved region.. By simulation results, we show that the proposed approach offers optimal bandwidth for MANET

A Mobile ad-hoc network (MANET) is an extremely testing lively network. They are self configuring, autonomous, quickly deployable and operate without infrastructure. Mobile ad hoc networks consist of nodes that cooperate to provide connectivity and are free to move and organize randomly. Nodes can connect and depart the network at anytime and should be in position to relay traffic. These nodes are often vulnerable to failure thus making mobile ad hoc networks open to threats and attacks. Communication in MANET relies on mutual trust between the participating nodes but the features of MANET make this hard. Nodes sometimes fail to transmit and start dropping packets during the transmission. Such nodes are responsible for untrustworthy routing. A trust based scheme can be used to track this behavior of untrustworthy nodes and segregate them from routing, thus provide trustworthiness. In this paper a trust based AODV protocol is presented which assigns a trust value for each node. Nodes are allowed to participate in routing based on their trust values. A threshold value is assigned and if the nodes trust value is greater than this value its marked as trustworthy node and allowed to participate in routing else the node is marked untrustworthy. This scheme increases PDR and decreases delay thereby enhancing the trustworthiness in AODV based MANET routing. The work is implemented and simulated on NS-2. The simulation result shows the proposed protocol provides more reliable and consistent data transfer compared with general AODV in presence of unpredictable and unreliable nodes in MANET.

Mobile ad hoc network is a self organized network with a collection of wireless nodes without a fixed topology and centralized administration among the nodes. There is an urgent need for trustworthiness in MANET, as the survival of the spontaneous network depends upon the trust and cooperation among different nodes. The nodes have unmitigated control over the data packets passed through them and so the malicious nodes may accomplish the control over the data packets, thus they may threat the normal nodes in the network. Here the need for establishing a trusted environment in MANET arises. Trusted environment increases the probability of a successful transaction and reducing the opportunities of being defrauded. Trust is used to determine the reliability and inter opinionative between nodes and their neighbors. Difference between actual and expected value of the node behavior determines the degree of trust of that node. In this paper first discuss the need for trusted environment, then the basic issues while designing trusted environment. Then survey some existing trusted models for MANET and point out some issues regarding with them. Based on these studies a solution suggested, dynamic fuzzy based trust model through a drop less route using AODV in MANET. Also advantages of the proposed model are discussed.

Performance of the video on demand system highly depends upon the efficient traffic processing. Video stream data processing becomes a very interesting area over the decade for its exponential rapid growth market. Existence packet flow control mechanism can’t handle the video streaming smoothly. Streaming video content sent in compressed form over the network and displayed by the viewer in real time. Stream data stream contains the audio and video data. A good policy is highly required to control the loss of video stream data over the high speed network. By efficient control mechanism of the video streaming to reduce the over burden load to the VOD system and increases the system performance of centralized as well as distributed VOD architecture. A good policy of the video stream control mechanism efficiently implements on the all types topologies. This paper presents the policy based traffic control mechanism for the video streaming in real time scenario.

Zone Routing protocol (ZRP) combines the best features of both proactive and reactive MANET routing protocol and hence comes under the category of MANET hybrid routing protocol. ZRP is based on the concept of zones where zone is defined based on the number of hops, the actual physical distance is not considered. The zone size is directly propositional to the distance between the sender and border nodes, so if the distance increases, the radio coverage of the sender node will not be able to reach the border nodes in the zone, so that the sender node will need to increase the number of broadcasts to find the border nodes in the zone, which will obviously increase the bandwidth utilization. Since effective utilization of bandwidth is one of the major issues faced by MANET routing protocols the paper proposes a modification for ZRP by considering physical distance of the nodes also as a factor in determining the Zone radius for the effective utilization of the bandwidth and an easy cost effective way to determine the distance between the nodes using triangulation. Moreover considering the actual distance leads to the selection of shortest path and thus decreases the delay in packet delivery.

Apart from voice services, data made its foray in cellular networks with 2.5G networks. Today, with 3G network already in place, the data requirements of mobile subscribers is very high. With the increasing demand for mobile internet and rich data services such as streaming media for audio and video, this data requirement is expected to multifold in near future. Correspondingly the existing network infrastructures will have to scale to satisfy this huge bandwidth demand in future. The simple solution for this is to build up new infrastructure. But huge investments are involved with it. So, network operators have started looking for the alternative ways of satisfying this data needs. Among many alternatives, mobile data offloading is a most promising one. This paper presents the extensive need, benefits, and technological solutions for Mobile data offloading.

Gigabit Ethernet Standard provides 1 Gbps bandwidth and is backward compatible with 10 Mbps (Ethernet) and 100 Mbps (Fast Ethernet). It can also be installed with lower cost than other technologies having similar speed. The performance studies of Gigabit Ethernet is more complex than Ethernet or Fast Ethernet protocols. In this paper we have described the implementation of Gigabit Ethernet design on FPGA using Altera’s Triple Speed Ethernet IP Core. The performance analysis of Gigabit Ethernet Standard has been studied using various physical media. This analysis includes performance measurements with different number of frames and frame lengths.

In this study, proposed Information Gathering Chronological Model (IGCM) design offers a large-scale questionnaire, i.e. a good reference for evaluating the prevalence of symptoms and sensations from the usage of mobile phones or wireless devices. The IGCM was applied to assess the possible health effects from mobile phones on population. The study was carried out as a survey by posting the questionnaire both the online and manual among the randomly selected 307 Indians. Mobile subscribers were assessed for self reported symptoms and sensations and safety management adopted during calling. A good number of mobile phone users were found to be associated with symptoms i.e., headache, ringing delusion, forgetfulness, increase in the carelessness, dizziness, extreme irritation, speaking falteringly, neurophysiologic discomfort, cell phone side ear temperature increase and speaking falteringly when analyzed the output of IGCM. Study concluded that proposed model IGCM has significance in order to monitoring and evaluating frequently available holistic information especially health care management by mobile phone subscribers.

The advent of code division multiple access (CDMA) technology has offered solution to the incessant termination of ongoing calls experienced in second generation networks. Seamless connectivity is now made possible as these networks provide an uninterrupted-transfer loop known as the overlap region, which must be effectively managed to ensure efficient handoffs. This contribution adopts a practical approach to the soft handoff problem, with concrete experimental solution that will benefit network operators and the wireless research community. We achieve this by studying an existing CDMA cellular network over a period of two months. Under ideal conditions, we adapt the existing data to the COST-231 Hata pathloss model and derive a soft handoff (SHO) probability model, peculiar to the study environment and generic to similar environments. In order to draw effective conclusions and advise on best practices, the model was simulated for various coverage areas and propagation exponents. Simulation results confirm that SHO thresholds should be carefully chosen in order to minimize network defects.

Mobile agents are active objects that can autonomously migrate in a network to perform tasks on behalf of their owners. Though they offer an important new method of performing transactions and information retrieval in networks, mobile agents also raise several security issues related to the protection of host resources as well as the data carried by an agent itself. Mobile agent technology offers a new computing paradigm in which a program, in the form of a software agent, can suspend its execution on a host computer, transfer itself to another agent-enabled host on the network, and resume execution on the new host. Mobile Agent (MA) technology raises significant security concerns and requires a thorough security framework with a wide range of strategies and mechanisms for the protection of both agent platform and mobile agents against possibly malicious reciprocal behavior. The security infrastructure should have the ability to flexibly and dynamically offer different solutions to achieve different qualities of security service depending on application requirements. The protection of mobile agent systems continues to be an active area of research that will enable future applications to utilize this paradigm of computing. Agent systems and mobile applications must balance security requirements with available security mechanisms in order to meet application level security goals.

A security solution has been introduced, which protects both the mobile agent itself and the host resources that encrypt the data before passing it to mobile agent and decrypt it on the visited host sides i.e. it transfers the URL to the Mobile Agent System that will pass that encrypted URL to the server where it will be decrypted and used. The methods of Encryption/Decryption used are a Public-key Cipher System and a Symmetric Cipher System that focuses on submitting data to the server securely. The proposed approach solves the problem of malicious host that can harm mobile agent or the information it contain.

Organic Transistor (OT) modeling, fabrication and applicability has undergone remarkable progress during last ten years. Organic Thin Film Transistors (OTFTs) have received significant attention recently because of their considerable utility. They can be fabricated at lower temperature and significantly reduced cost as compared to Hydrogenated Amorphous Silicon Thin Film Transistors (a-Si: H TFTs). Fabrication of OTFTs at low temperature allows utilization of wide range of substrates, thereby permitting usage of organic transistors as future candidate for many low-cost electronics applications that require flexible polymeric substrates such as RFID tags, smart cards, electronic paper, and active matrix flat panel displays. This paper provides detailed insight of OTFTs, their operating principles, device materials and various structures such as Top Gate Top Contact (TGTC), Top Gate Bottom Contact (TGBC), Bottom Gate Top Contact (BGTC) and Bottom Gate Bottom Contact (BGBC). Although OTFTs find tremendous and widespread applications, but is marred by few limitations related to factors such as speed, compatibility, stability, degradability and variability. This paper comprehensively discusses the performance and limitations of OTFTs.

Supervised classifiers are limited by the annotated corpora available. Active learning is a way to circumvent this bottleneck, reducing the number of annotated examples required. In this paper, we analyze the benefits of active learning combined with bagging applied to Quotation Start, Noun Phrase Chunking and Text Chunking tasks. We employ query-by-committee as query strategy to actively select examples to be annotated. By using these techniques, we achieve reductions up to 62.50% on the annotation effort depending on the task to obtain the same quality as in passive supervised learning.

A data warehouse stores historical information, continuously being generated over time, to support decision making. The queries posed for decision making are usually exploratory, long, complex and analytical in nature. These queries, when posed against a large and continuously growing data warehouse, consume a lot of time for processing and thereby resulting in high response times. This problem of high response time can be addressed by constructing materialized views on the data warehouse. These views, which store data along with its definition, cannot be arbitrarily constructed as they need to contain relevant and required information for answering most future queries. The approach proposed in this paper attempts to identify such information, from previously posed queries on a data warehouse, using clustering and association rule mining techniques. The information identified using the approach is likely to answer most future queries in reduced query response times. As a result, the decision making would become more efficient.

Nowadays with rapidly growing databases in manufacturing industries it’s really an unmanageable timing problem to analyze them and to make decision from them. Studying this type of problem using data mining techniques leads more clarification for manufacture and also for better research work. Here in this paper a similarity based cluster technique is proposed on engineering materials database and implemented using c sharp .net.

An encryption method is proposed that uses self-invertible matrix, modular function, Non-Linear shift register and the chaotic map known as Logistic. Parameter of Logistic map act as secret key. As chaotic system used in this algorithm is 1-D system, the key space is lesser than 2

100

which shows that the method is weak against Brute-force attack but identifiability property of the selected key from key space assures its strength against the attack. Key sensitivity and plaintext sensitivity of the key chosen from key space for the algorithm is analyzed and its strength against known-plaintext attack is also tested and conclusions are derived.

In this paper, we propose a new technique for checking the relevancy of sessions created by visitors on a web-page for measuring the web-page ranking, since session of a web-page is considered as an important parameter for web-page ranking calculation in a search engine. It is assumed that session on a web-page depends on the relevancy of the web-page contents with respect to the requirement. A longer session on a web-page may not yield high relevancy of the web-page, hence a threshold value (THV) is considered for individual web-page based on the contents to avoid the probable noise. The threshold value (THV) is calculated by Keyword Matching Index (Kindex) and Data Transfer Speed of the client-server. The Kindex is measured by implementing fuzzy logic on Pattern Matching of requirement and web-page contents. Field Matching information is fetched through hierarchical database.

A Mobile Ad hoc Network (MANET) is a collection of wireless nodes, forming a temporary network without using any fixed architecture. Communications among the nodes of a MANET are accomplished by forwarding data packets for each other, on a hop by hop basis. The research in this area is commonly simulation based as not many ad hoc networks are currently deployed. Based on routing topology, routing protocols in MANETS are categorized as flat routing and hierarchical routing. In flat routing protocols like DSR and AODV, every node has assigned uniform functionalities. But their performance degrades as the network size grows. Hierarchical routing protocols like CGSR and HSR maintain hierarchy on entire network. But overhead may be high to maintain hierarchy in the mobile network environment. In this paper we propose an On Demand Hierarchical Routing protocol, in which certain number of intermediate nodes present on the route-path are selected as way-nodes and the entire route-path is partitioned into segments by these way-nodes. We call this protocol as Way Directing Node Routing (WDNR), in which the source and destination nodes run a high level inter-segment routing approach. Within each segment it runs a low-level intra-segment routing protocol. The main advantage of this protocol is, when a link on a route-path fails due to node mobility, instead of discarding entire route and rediscovering the fresh route between source and destination, the broken link can be repaired locally. Our model is light weight compared to basic hierarchical routing, as the selection of way-nodes is made only for active routes, on an on-demand basis. Our WDNR protocol uses AODV as intra-segment routing protocol and DSR as inter-segment routing protocol. It mainly solves the scalability problem of flat routing and overhead problem of hierarchical routing. WDNR protocol also exhibits the functionality required to scale large networks and reduce the overhead in hierarchy maintenance. Simulations are carried out in GloMoSim. The simulation results show that WDNR scales better for larger networks with higher than 800 nodes, incurring about 50 to 70 percent less overhead than AODV protocol, while other performance metrics are comparable to basic DSR and AODV.

Search Engine is a Web-page retrieval tool. Nowadays Web searchers utilize their time using an efficient search engine. To improve the performance of the search engine, we are introducing a unique mechanism which will give Web searchers more prominent search results. In this paper, we are going to discuss a domain specific Web search prototype which will generate the predicted Web-page list for user given search string using Boolean bit mask.

Steganography is a process of secret communication where a piece of information or secret message is hidden in such a way that the very existence of the secret information remains concealed without raising any suspicion in the minds of the viewers and hence preventing its detection. This is generally achieved by embedding a piece of information inside another piece of innocent looking information and can be a spatial or time or transform domain method. All these methods hide information in different types of media such as text, image, audio, video etc. Amongst these varieties of available media, digital images are more commonly used for implementation of data hiding techniques because of their size and popularity. This paper uses a spatial domain LSB substitution method for information embedding and Arnold transformation is successively applied twice in two different phases in order to achieve higher security. The system is tested and validated against a series of standard gray scale images and the results thus obtained are found to be highly promising.

Mobile Ad-hoc Networks (MANETS) are infrastructure less self-organizing and self-configuring network. The nodes in MANETS are highly mobile and the routing mechanisms of these may vary depending on various applications. This poses serious challenges to routing and reliability. Reliability and reachability are the two important terms related to dissemination of data in MANETs. This paper studies the AODV protocol in MANET. And also try to understand the multiple connections in MANET under various situations. Several issues have been identified in the creation of multiple connections. The prominent issue recognized is the bandwidth of a node in creation of multiple connections. This poses major concern in connection establishment and connection maintenance. This paper also proposes a new idea of improving the simultaneous multiple connections with the consideration of bandwidth of each node.

Pervasive computing is the next thrust area for the researchers, service providers and end users alike but the challenges associated for them are equally grilling. Ad-hoc availability of resources makes it extremely important for the stake-holders to keep their Software Architecture as flexible as possible in order to maintain the Quality of Service. This work provides a solution to the dynamic environment, posed by pervasive computing by suggesting a metadata driven adaptive framework, which can be modeled into existing Architecture Description Languages (ADLs) as well as directly implemented on existing platforms. This work reflects a conceptual framework, as an extension to existing work in this field of adaptive software architectures that can be further customized into more sophisticated system as per the requirements of a pervasive environment or any other similar application area.

Transmission Control Protocol (TCP) is the most commonly used transport protocol on the internet. The performance of TCP in wireless network is not satisfactory as it was originally designed for wired networks. This paper proposes Dynamic DCF Backoff Algorithm(DDBA) to improve the throughput of TCP in wireless mobile environment. The proposed DDBA minimizes TCP Instability problem initiated by wrong link failure information from the source node. The simulation in NS2 shows improved TCP performance in Grid, Cross and Random topology of wireless networks incorporating mobility of nodes.

Clustering methods divide the dataset into groups of similar objects called as clusters. Two objects in different clusters are dissimilar and objects in the same cluster are similar. Evaluation of clustering results is known as cluster validation. Cluster validation can be of different types. Internal cluster validation indices measure the quality of the clusters based on the intrinsic properties of the data. External cluster validation is based on external information about the data. The advantage of internal validation is that external information is not required. But using small amount of external information can make unsupervised clustering technique using internal cluster validation for finding optimal clustering solution achieve better results. The advantage with supervised clustering technique using external validation is that clusters confirming to class distribution are obtained. But using intrinsic information present in the data can prevent over fitting of data by supervised learning technique using external validation. In this paper we propose various hybrid cluster validation indices using internal and external cluster validation indices. The advantage with hybrid indices is that validation is done using both intrinsic information of data and available external information.In this work we focus on hybrid cluster validation indices for semi-supervised clustering.

Wireless sensor networks (WSN) provide the availability of small and low-cost sensor nodes with capability of sensing physical and environmental conditions, data processing, and communication. These sensor nodes have limited transmission range, processing and storage capabilities as well as their energy resources. Routing protocols for wireless sensor networks are responsible for maintaining the energy efficient routes in the network and have to ensure extended network lifetime. In this paper, we propose and analyze a new approach of routing by clustering. The new cluster head selection approach by a homogeneous sensor node (having same initial energy) in wireless sensor network has been proposed, which involves choosing the cluster head which lies closest to the midpoint of the base station and the sensor node. Our proposed routing algorithm is related with energy and distance factors of each nodes. This scheme is then compared with the traditional LEACH protocol which involves selecting the cluster head which is nearest to the particular node. We conclude that the proposed protocol effectively extends the network lifetime with less consumption of energy in the network.

Identifying the smallest portion of the image that represents the entire image is a basic need for its efficient storage. Texture can be defined as a pattern that is repeated in a specific manner. The basic pattern that is repeated is called as Texel(Texture Element). This paper describes a method of extracting a Texel from the given textured image using K means clustering algorithm and validating it with the entire image. The number of gray levels in an image is reduced using a linear transformation function. The image is then divided in to sub windows of certain size. These sub windows are clustered together using K-means algorithm. Finally a heuristic algorithm is applied on the cluster labels to identify the Texel, which results in more than one candidate for Texel. The best among them is then chosen based on its similarity with the overall image. The similarity between the Texel and the image is calculated based on then Normalized Gray level co-occurrence matrix in the maximum gradient direction. Experiments are conducted on various texture images for various block sizes and the results are summarized.

SMC is a problem of n parties with inputs (x

1

, x

2

…x

n

) , hand over their inputs to third party for computation f(x

1

, x

2

…x

n

) and third party announces the result in the form of y. During joint computation of inputs, all the organizations involved in computation wish to preserve privacy of their inputs. So need is to define a protocol which maintains privacy, security and correctness parameters of SMC. In this paper, single third party and multi third party model are defined and compared. The probabilistic evidences for single and multi third party SMC model have been analyzed with security analysis graphs. In this paper, we have also worked on identification and reduction of malicious conduct of TTPs in multi TTP environment.

Attention has been drawn to mobile devices, which show that the success will be the portability of applications from one platform to the other. With integration of 3D virtual objects into real environment in real time thus allowing student to relate with their physical environment and also making the subject more interesting. This study carry out based on the understanding of different types of learning theories, concept of mobile learning and mobile augmented reality and discusses how applications using these advanced technologies can improve learning process.

The Secured Transport System by authenticating Vehicles and Drivers using RFID is aimed at providing a secure transportation mechanism. As the vehicular traffic is growing exponentially, monitoring the authenticity of drivers and vehicles is a hurricane task for RTO (Regional Transport Office). Though monitoring is achieved to some extent by Global Positioning Systems (GPS), currently it is restricted to taxi cabs. Our proposed work utilizes server-client methods used in other areas. Each vehicle will be embedded with a client module circuitry and RTO offices will host servers. Vehicles’ and Drivers’ information gathered by client is validated by Servers and thus RTO can keep track of various credentials like vehicle insurance, driving license of every vehicle plying on streets.

Data storage management is one of the most challenging issues for Grid resource management since large amount of data intensive applications frequently involve a high degree of data access locality. Grid applications typically deal with large amounts of data. In traditional approaches high-performance dedicated servers are used for data storage and data replication. This allows opportunistic grids to share not only the computational cycles, but also the storage space. This paper explains new mechanism for Dynamic and Scalable Storage Management (DSSM) in grid environments is proposed. The storage can be transparently accessed from any grid machine, allowing easy data sharing among grid users and applications. The concept of virtual ids that, allows the creation of virtual spaces has been introduced and used. The DSSM divides all Grid Oriented Storage devices (nodes) into multiple geographically distributed domains and to facilitate the locality and simplify the intra-domain storage management. Grid service based storage resources are adopted to stack simple modular service piece by piece as demand grows. To this end, we propose four axes that define: DSSM architecture and algorithms description, Storage resources and resource discovery into Grid service, Evaluate purpose prototype system, dynamically, scalability, and bandwidth, and Discuss results. Algorithms at bottom and upper level for standardization dynamic and scalable storage management, along with higher bandwidths have been designed.

In recent days terrorism poses a threat to homeland security. It’s highly motivated by the “net-war” where the extremist are organized in a network structure. The major problem faced is to automatically identify the key player who can maximally influence other nodes in a large relational covert network. The nodes and links are represented in the form of a directional semantic graph where each node is related with more than one relationship with the other node. The behaviors of nodes are analyzed based on the semantic profile generated. This analysis helps the crime analyst to judge the key player for a criminal activity. The semantic profile is obtained by choosing carefully the path types that suits best for a specific node. The selection strategies can be generalized as path equivalence and constraint based. The strategy further supports the variable relaxation approach by grouping all the paths with the same sequence of relations as a single path type. This can also be made as user friendly by letting the user to represent their own preferences on the nodes and links.

Operating System (OS) as the root of trust for all applications running on the computer systems and plays an important role in information security. If the network or the software in application level that are executing on the operating system be unsecure, it is expected that OS as a defensive layer or in another words as the last defensive layer protects the security of information. In this paper, first, we extract and classify a vast spectrum of security features which has been used in multi-purposed OS, and then attribute them to three levels of low, medium and high. Our case study indicates how it is possible to evaluate OS security and specify the security level of an OS.

Ad hoc networks are wireless networks without a fixed infrastructure, and are usually established on a temporary basis for a specific application like emergency rescue or battle field communication. Energy management in wireless networks is the process of managing the sources and consumers of energy in a node or in the network as a whole for enhancing the lifetime of the network. Since, most of the mobile nodes in the network are equipped with low power batteries, it could be difficult for a mobile device to sustain for a long time if it send and receive data more often. To solve this problem here we describe the power management issues in mobile nodes using modified Zone Routing Protocol (ZRP) and it was simulated using NS2 simulator.

Future generation 4G wireless network is designed for flawless and continues connections between devices of several independent wireless networks like WLAN, GPRS and so on. Heterogeneous wireless networks will be dominant in the next-generation wireless networks with the integration of various wireless access networks. One of the most challenging problems for coordination is vertical handoff, which is the decision for a mobile node to handoff between different types of networks in heterogeneous network. Handoff is based on received signal strength comparisons; in this paper we develop a Vertical Handoff strategy for 4G network based on bandwidth and Power (Signal Strength) between different networks .we compare the results with handoff mechanism depending upon only signal strength. Results show a significant performance improvement of the proposed system over the signal strength driven handoff or connectivity driven handoff.

Information’s security and delicacy make the electronic systems in a challenging and chasing phase when it is passed on from an end to other via Internet. In today’s world, as the necessity and importance of sensitive information are growing with new advancements and technologies, they become more prone to attacks and oriented towards the insecure environment. Attackers always want just an attack on such information to either to use it or intercept it. In this direction, many researchers have put their good efforts not only just to provide information security, instead they also consider the related primary security concerns, like confidentiality, access control, integrity along with the quality issues of reliability, robustness, usability etc. This effort included and presented a technological advancement based comparative study of various Sensitive Information Security (SIS) models and their proposed methods, algorithms, and experimental results. This study provides a great forum and better understanding of these models with their respective advantages and disadvantages.

Introduction of Smart phones redefined the usage of mobile phones in the communication world. Smart phones are equipped with various sophisticated features such as Wi-Fi, GPS navigation, high resolution camera, touch screen with broadband access which helps the mobile phone users to keep in touch with the modern world. Many of these features are primarily integrated with the mobile operating system which is out of reach to public, by which the users can’t manipulate those features. Google came up with an innovative operation system termed as ANDROID, which is open system architecture with customizable third party development and debugging environment which helps the user’s to manipulate the features and to create their own customizable applications.

In this paper, ‘Emergency Based Remote Collateral Tracking System’ application using Google’s Android Mobile Platform is addressed. Emergency is divided into three categories: heart beat based emergency, security threats like personal safety and road accidents. This application is targeted to a person who is driving a vehicle. Heart rate monitoring device is integrated with our application to sense the heart beat of a person driving the vehicle and if there is any abnormalities in the heart beat, then our application performs a dual role. One in which, application uses a GPS to track the location information of the user and send those location information as a message via SMS, email and post it on Facebook wall Simultaneously, an emergency signal is sent to Arduino Microcontroller.

Road accidents are quite common, this application is also designed to detect the accident using the sensors in the Android Mobile. Security threat can occur anywhere, our application also answers for personal safety, when the user interacts with the application by pressing the button, then automatically the application generates the geographical information and sends that location information via SMS and email to a pre-stored emergency contact and the same information will be posted on user’s Facebook wall. This application is written in JAVA programming language which runs on Eclipse Integrated Development Kit.

Transition and Mobility management has been a growing concern with numerous problems originating from roaming between IPv6 and IPv4 access networks owing to ever-growing research. Hence the various architectures concerning transition/mobility among IPv6 and IPv4 are studied. It is an observed fact that, there is still a need for more research to be done on the IPv6 transition in order to solve many problems that are not yet resolved. Henceforth, AIMM-I46 architecture has been proposed and designed as an integrated IPv4/IPv6 addressing, mobility and transition mechanism. In this paper, the performance of AIMM-I46 architecture analyzed when different data size, link capacity are used. Adventnet Network Simulator Toolkit 7 is used to evaluate the performance of AIMM-I46, using different performance evaluation metrics such as data loss rate, throughput, packet overhead and latency which have significant implications on any protocol performance. The simulated results shows that the proposed architecture provides inter mobility and interoperability between IPv4 and IPv6 networks.

We propose an algorithm to determine stable connected dominating sets (SN-CDS) for mobile ad hoc networks (MANETs) using the notion of a “strong neighborhood,” defined based on a “threshold neighborhood distance ratio” (

TNDR

≤ 1). A node

j

at a physical Euclidean distance of

r

from node

i

is said to be in the strong neighborhood of node

i

if

r

/

R

≤

TNDR

where

R

is the fixed transmission range of all nodes in the network. A non-CDS node is said to be covered it at least one of its neighbor nodes is in the SN-CDS. The proposed algorithm prefers to include a covered node with the maximum number (≥ 1) of uncovered neighbors into the SN-CDS; ties are broken using node ids. The algorithm stops when every node is either in the SN-CDS or has at least one neighbor node in the SN-CDS. If

TNDR

= 1, then SN-CDS corresponds to the maximum-density based CDS (MaxD-CDS) algorithm, a heuristic to approximate a CDS with the minimum number of constituent nodes. We observe that an SN-CDS (with TNDR < 1) has a significantly longer lifetime than a MaxD-CDS and for a given condition of network density and node mobility, the difference in the lifetime increases as the value of TNDR decreases. The tradeoff is lower connectivity as well as a larger constituent node size and hop count per path.

For many years, file replication and dereplication in distributed computing environment has been researched to enhance and optimize the scalability of the entire system. Although numerous work have been proposed on the issues of file replication, a comprehensive approach still misses out on various fronts. An effort has been made in the present work to propose a reliable and comprehensive file replication and memory aware dereplication mechanism for a trusted private cloud, based on the file threshold. The proposed approach introduces a File Replication Server (FRS) that is responsible for replicating the file on peer FRS, when the file threshold limit is reached. The proposed approach handles file replication, dereplication, access and performance transparency to the system, thereby ensuring the replication and dereplication decisions about the files in a seamless and efficient manner. The approach is simulated on JAVA platform. A comparative study of the proposed approach with the Request Reply Acknowledgement (RRA) and Request Reply (RR) protocol is presented, showing the significant reduction by 37.5% to 58%, in terms of total number of messages exchanged for file replication.

Hierarchical Mobile IPv6 introduced Mobility Anchor Points to reduce the signaling overhead due to frequent change of Access Routers by the Mobile Nodes. In order to increase the scalability and to improve the overall performance of the network multiple layers of MAPs are introduced. This creates the problem of optimal MAP selection by the MNs. Several MAP selection schemes have been proposed for this purpose. This paper considers three MAP selection schemes: Furthest MAP selection scheme, Nearest MAP selection scheme and Mobility based MAP selection scheme. All the three schemes are compared with respect to signaling overhead, handoff latency and tunneling cost in multi layer MAP network architecture. Analytical results show that the furthest MAP selection scheme has minimum inter domain binding update cost, the nearest MAP selection scheme has low cost in other respects except inter domain BU cost but the Mobility based MAP selection scheme offers most optimal performance in all respects.

Wireless Sensor Network (WSN) is a self-organized wireless ad-hoc network comprising large number of resource constrained devices called sensors. Usually sensors battery drainage is the main constraint in developing powerful WSN applications. Accordingly, a power conserving strategy must be implemented in all WSN layers. This paper focuses on the network layer which includes routing techniques as a main participant in power conserving applications. The main goal of the present work is to develop a routing technique based on genetic algorithm which aims to minimize total consumed power per round; hence lifetime is maximized compared to other techniques. The proposed technique enables sensor network to continue its operation during the continuous sensor failure without introducing additional control packets. Genetic algorithm is used in the proposed technique to find the minimum power ring which passes through all sensors and the base station. The algorithm operates on the base station only to save sensor’s memory, processing resources, and indeed the power consumption.

The hierarchical macro/femto cell WiMAX networks are observed to be quite promising for mobile operators as it improves their network coverage and capacity at the outskirt of the macro cell. However, this new technology introduces increased number of macro/femto handoff which inturn may affect the system performance. Users moving with high velocity or undergoing real-time transmission suffers degraded performace due to huge number of unnecessary macro/femto handoff. Our proposed handoff decision algorithm eliminates the unnecessary handoff while balancing the load of the macro and femto cells. The performance of the proposed algorithm is analyzed using Continuous Time Markov Chain (CTMC) Model. In addition, we have also contributed a method to determine the balanced threshold level of the received signal strength (RSS) from macro base station (BS). The balanced threshold level provides equal load distribution to the macro and femto BSs. The balanced threshold level is evaluated based on the distant location of the femto cells for small scaled networks. Numerical analysis shows that threshold level above the balanced threhold results in higher load distribution to the femto BSs.

In this study, we present a transmission-control middleware, which enables an Android terminal to select a suitable TCP in a WLAN Environment. Various approaches toward developing a congestion control algorithm of TCP have been proposed to prevent congestion. Some of these approaches are loss based whereas others are delay based to predict network traffic, and their hybrid type also exists such as Compound-TCP[9] and TCPIllinois[10]. However, all of these approaches are designed to allow each terminal to run independently. Moreover, in the case of a mobile terminal, its TCP is limited to behave modestly to avoid filling the bandwidth. In this paper, we suggest a middleware that exchanges communication conditions to predict traffic on the basis of the number of communication terminals connected to the same access point. In the future, we will improve the middleware to predict the values of the Congestion Window of the other terminals.

A special class of mobile application has been made feasible by Mobile ad-hoc networks. They benefit from the fast deployment and reconfiguration of the networks, are mainly characterized by the need to support many-to-many interaction schema within groups of cooperating mobile hosts and are likely to use replication of data objects to achieve performances and high data availability. This strong group orientation requires specialized solutions that combine adaptation to the fully mobile environment and provide the adequate level of data and service availability with certain amount of fault tolerance. In this paper performance analysis of existing Location-based MANETs techniques with respect to various issues they address such as Data availability and data consistency, Partition detection, etc., is carried out.

It is a very common practice to use network simulators for testing different network performance parameters before the real-life deployment of such a network. Apart from ns-2, few other recent network simulators have come into existence today and are gaining in more popularity. In this paper, we survey some of the widespread network simulators that are in use today, and try to evaluate their performance over certain parameters by setting up identical network simulation scenarios.

"There is a great deal of difference between an eager man who wants to read a book and a tired man who wants a book to read" - G.K. Chesterton

With the colossal collection of traditional and digital including books, journals, audio materials, photographs, e-journals, e-books, web resources and more in recent years, finding an o‘nymous item is becoming more and more difficult, resulting in a number of practical conflicts. The accessing and the procurement of the details pertaining to a publication is becoming an ubiquitous problem. Widespread use of wireless technologies paired with the recent advances in the wireless applications, manifests that digital data dissemination could be the key to solve emerging problems. Wireless Sensor Network technology has attracted increased attention and is rapidly emerging due to their enormous application potential in diverse fields. This buoyant field is expected to provide an efficient and cost-effective solution to the effluent problems. This paper proposes a SmArt LibrARY (SALARY) System based on wireless sensor network technology which provides advanced features like automatic update in the addition/deletion of a publication, automated guidance, and item reservation mechanism. The paper describes the overall system architecture of SALARY from hardware to software implementation in the view point of sensor networks. We implemented a full-fledged prototype system for library management to realize the design functionalities and features mentioned. Our preliminary test results show that the performance of this WSN based system can effectively satisfy the needs and requirements of existing integrated library system hassles thereby minimizing the time consumed to find the slot of thou publication, real-time information rendering, and smart reservation mechanisms.

One of the important and challenging problems in the design of ad hoc networks is the development of an efficient routing protocol that can provide high-quality communications among mobile hosts for that proposing new protocol to evaluate the node lifetime and the link lifetime utilizing the dynamic nature, such as the energy drain rate and the relative mobility estimation rate of nodes. Integrating these two performance metrics by using the proposed route lifetime-prediction algorithm select the least dynamic route with the longest lifetime for persistent data forwarding and based on quadrant. our proposed route Lifetime-prediction protocol in a exploring dynamic nature routing for large scale network (LEDNR) protocol environment based on Ad hoc on demand distance vector routing (AODV).

The mobility models are used to represent the unpredictable movement pattern of the nodes in Mobile Ad-hoc Network (MANET) and give us an idea regarding their location, velocity and acceleration change over time. These models are used for simulation purpose in standard software tools such as QualNet, ns-2 etc. This paper evaluates the performance of routing protocols for mobility models such as Random Way Point (RWP), Random Walk (RW) and Random Direction (RD) under idealistic and realistic conditions based on a parameter termed as Probability of Reachability (POR). The POR is defined as the fraction of reachable routes to all possible routes between all pairs of sources and destinations. For this purpose a simulator is designed in MATLAB. We observe a marked difference in value of POR under idealistic and realistic conditions.

This paper deals with the application of concept of identifiability based on output equality approach on chaotic ciphers developed using 2-D chaotic maps, Duffings and Arnolds Cat map and they are named as Duffings and Arnold’s Cat, according to the map used. Due to the less key space generally many chaotic cryptosystem developed are found to be weak against Brute force attack which is an essential issue to be solved. Thus, concept of identifiability proved to be a necessary condition to be fulfilled by the designed chaotic cipher to resist brute force attack, which is an exhaustive search. As 2-D chaotic maps provide more key space than 1-D maps thus they are considered to be more suitable. This work is accompanied with analysis results obtained from these developed cipher. Moreover, identifiable keys are searched for different input texts at various key values. The ciphers are also analyzed for plaintext sensitivity and key sensitivity for its validity to provide security.

Autonomous Under Water Sensor Networks UWSNs form distributed amorphous computing environments. Efficient resolution for an unreachable UWSN which includes failure-prone nodes will require strategies that are as simple as possible in computations and local communications, to facilitate self-organization. Localization of Under Water Sensor Networks UWSNs is the most challenging and essential task. In this paper we propose a localization technique for UWSNs which is implemented using a self-organizing localizing algorithm. When acoustic waves propagate through a medium, it travels with varying speed. This change in speed of sound wave is highly influenced by ocean parameters. In our proposed work we study the effect of sound speed on localization algorithm for Underwater Sensor Networks. The results show that our proposed localization technique performs better.

This paper presents an analytical model for estimating throughput and energy consumption in B-MAC protocol for Wireless Sensor Networks. The design includes transmission power control and multi-hop transmission of frames through adjusted transmitted power level. Proposed model reduces collision with contention level notification. The proposed model has been simulated using MATLAB. The simulations reveal better results for throughput and energy consumption of the proposed model as compared to B-MAC protocol.

In the changing business environment, where enterprise users are expected to handle critical tasks and decision-making in real-time, it has become a business imperative to stay competitive and agile by adopting mobility to handle business needs. In a typical enterprise, the entire business value chain is geographically fragmented which drives the need to mobile-enable the existing enterprise applications.

This paper highlights the key customer pain areas in Enterprise Mobility adoption across the enterprises. It, not only addresses the Critical Success Factors for enterprise mobility enablement but also outlines the business needs to rapidly create enterprise mobile solutions across all lines of businesses.

The paper enlightens the value impact of enterprise mobility on workplace, organizations and technology and discusses the critical growth factors, key enablers and transformational strategies along with enterprise mobile application components.

Moreover, the paper outlines key design considerations, recommendations and enterprise mobility value proposition to potential organizations in terms of tangible and financially oriented results.

This paper present a dynamic guard channel assignment technique based on a two low layer of hierarchical cellular architecture which evaluates the QoS of (LMST) low speed and (HSMT) high speed moving terminals in an indoor area. The lower layer of the proposed architecture is based on a femto cellular solution for absorbing the traffic loads of LSMT. The higher layer is based on a picocell solution for absorbing the traffic load of the HSMT. The result show that using the optimum number of channels and adjusting dynamically the number of guard channels in each layer, the QoS of LSMT and HSMT are evaluated, having a small negative effect on the QoS of LSMT.

Content-based publish-subscribe is emerging as a communication paradigm able to cope with the needs of scalability, flexibility, and reconfigurability typical of highly dynamic distributed applications. However very few efforts concentrates on application development and cost analysis for content based publish subscribe model in real time mobile environment. In this paper we illustrate the application developed for content based publish subscribe in wired and wireless network. Also we present the result of cost analysis performed using cost model in real time mobile environment. The result of the experiment which is carried out using mobile devices show accordance with cost analysis, which verifies the correctness and usefulness of cost model.

Energy conservation is an important issue in Mobile Ad Hoc Networks (MANETs) as most of the nodes are powered by a battery source which has limited energy reservoir and it also becomes very difficult to recharge or replace the battery of the nodes. Existing MANET routing protocols s. a. DSR and AODV use common transmission range for transfer of data and does not consider energy status of nodes. This paper discusses a new energy aware scheme (EA-AODV) based on AODV using variable transmission range. The protocols are simulated using Network Simulator-2 and comparisons are made to analyze their performance based on energy consumption and network lifetime metrics. The results show that EA-AODV makes effective node energy utilization.

The use of speech recognition [2] [3] techniques in many practical applications has demonstrated the need for an Automatic speech Recognizer (ASR), it is a complex machine developed with the purpose to understand human speech. The conventional methods for speech recognition, such as HMM (Hidden Markov Model) and DTW (Dynamic Time Warping), are very complicated and time consuming. To apply Digital Signal Processor TMS320C6713 Digital signal processing Starter Kit (DSK) board is an attempt to implement a laboratory based Automatic speech Recognizer [1]. The proposed approach in this paper simplifies the algorithm using Linear Predictive Cepstral coefficients (LPCC) and Vector Quantization (VQ). The paper includes a performance evaluation of the above techniques on Matlab and application evaluation on DSK board. The database on which the training and testing was carried out is created in-house laboratory under calm and noise free environment.

Wireless networking is becoming an increasingly important and popular way of providing global information access to users on the move. One of the main challenges for seamless mobility is the availability of simple and robust vertical handoff algorithms, which allow a mobile node to roam among heterogeneous wireless networks. The next generation of mobile networks will support not just simple mobile connectivity but access to evolving smart space environments. In this paper, we propose a novel vertical handoff decision algorithm for overlay wireless networks consisting of heterogeneous wireless environment. This paper presents the proposal of optimal network selection algorithm in wireless heterogeneous environment that is based on TOPSIS method when solving the multi criteria analysis. The target network is selected using TOPSIS based decision algorithm which, in addition to usual parameters, also takes a prediction of the RSS into account

Congestion is a major problem in mobile ad-hoc networks. In mobile ad hoc networks congestion creates delay in transmission and also loss of the packet that causes wastage of time and energy on recovery. The Wireless Networks have to play an important role to adopt and execute a large no of innovative application. New challenges have come considering the major limitations of the ad hoc network like node’s limited processing power, balance the load of network (to maintain the computation of the node). To overcome the above problem some algorithm is invoked and there may be huge amount of packet loss and this leads to decrease the lifetime of the network. The objective of our proposed algorithm is to identify the congestion areas between source and its neighboring nodes to the destination and thus it will help to avoid the congestion of the network in the intermediate links and also minimize the packet loss in the network. Using a new mathematical model considering the swarm-based ant intelligence concept, we found an efficient congestion control mechanism (Ant’s probabilistic transition rule).

The crucial decision issues in MANET like load balancing or link discovery after an existing link breakage for routing are dependent on the mobility of the participating nodes. These decisions will be accurate if the changes within the network due to mobility can be apprehended efficiently. In this paper, we have proposed a formal modeling approach to assess the changes in terms of node density in a zone based network. A two layered Colored Petri net is proposed for describing the mobility of a single node and the resulting changes within a network due to this mobility. The model is expected to provide useful information through analysis and that helps a lot for taking these critical decisions.

Mobile object tracking is a key application of wireless sensor network based surveillance systems. Sensor deployment is an important factor in tracking performance. In this paper, we consider the problem of optimal sensor deployment for mobile object tracking using the node sequences model without considering the sensing quality and the specific movement trace. We determine that there are three patterns that can reduce tracking error rate: regular tiling pattern, random pattern, and irregular pattern. We analyze the properties of these patterns and provide an upper bound of the tracking error rate for each pattern in the worst case scenario. We also provide theoretical analysis and simulation evaluations to demonstrate that the irregular pattern outperforms the other two patterns.

Recent advances in mobile communication and development of sophisticated equipments lead to the wide spread use of Location Based Services (LBS). A major concern for large-scale deployment of LBSs is the potential abuse of their client location data, which may imply sensitive personal information. Protecting location information of the mobile user is challenging because a location itself may reveal user identity. Several schemes have been proposed for location cloaking. In our paper, we propose a generic Enhanced LBS Reference Model (ELRM), which describes the concept, the architecture and the functionalities for location privacy in LBS. As per the architecture, the system ensures location privacy, without trusting anybody including the peers or LBS servers. The system is fully distributed and evaluation shows its efficiency and high level of privacy with QoS.

The lack of static infrastructure causes several issues in mobile Ad Hoc network, such as energy utilization, node authentication and secure routing. In this paper we propose a new scheme for energy efficient secure routing of data packets in MANET. This approach will reduce the computational overhead to make it more energy efficient than existing schemes. As there is no stationary infrastructure,each node in MANET acts a router that forwards data packets to other nodes. Therefore selection of effective, suitable, adaptive and robust routing scheme is of utmost importance. We have reduced the amount of network activity for each node required to route a data packet. This leads to lesser wastage of energy and increases security.Our simulation results will show how this is energy efficient and secure. Finally we have discussed how this scheme prevents various attacks which may jeopardize any wireless network.

In MANET environment intermediate nodes on a communication path are expected to forward packets of source node towards destination node. This enhances the communication range of mobile nodes beyond their wireless transmission range. From the security point of view a proper mechanism should be there, so that nodes can trust each other for safe delivery of their data. Therefore trust establishment is considered as an important approach to defend safe communication in MANET. In the previous years several trust models have been proposed to enhance the security of mobile ad hoc network. However an important factor, mobility of node, before establishing the trust relationship among nodes is yet not discussed. In this paper trust model is been proposed. In this model the Trustworthiness of each node is calculated with the mobility factor. Minimal configuration, quick deployment and absence of central governing authority make ad hoc networks suitable for emergency situations. Natural disasters, military conflicts are some real life scenarios where trust among nodes is very important. Thus this model will be very effective in these situations. Speed of node is used to decide on the trust value for the trustee node.

Applications are generally designed and developed with little regards to security consideration. Fortunately, there is abundant of processes and technologies today that is available that can be used to easily secure an application while it is in the maintenance phase. In this paper, we have discussed how we can use symmetric and asymmetric cryptography methods and security architecture can be created to protect a system from various cipher attacks after deployment.

Recently, Xiao

$et \ al.$

proposed a strong designated verifier certificateless signature scheme. Zhang

$et \ al.$

claimed that Xiao

$et \ al.$

’s scheme is vulnerable to key replacement attacks. In this paper, we show that Zhang

$et \ al.$

’s cryptanalysis on Xiao

$et \ al.$

’s scheme is incorrect and Xiao

$et \ al.$

’s scheme is insecure against key replacement attacks. On the other hand, Li

$et \ al.$

proposed a certificateless signature scheme without

MapToPoint

. It is shown that an adversary who replaces the public key of a signer can forge valid signatures for that signer without knowledge of the signer’s private key.

Information technology is facing lots of problems, while transmitting sensitive data and confidential data due to rapid growth of technology. The sensitive data is intended to share between only authorized persons, not for all. Information security concentrates on sensitive knowledge pattern that can be exposed when extracting the data. Therefore, researchers, for a long time period, have been investigating paths to improve privacy for sensitive data in information security analysis task process. So, many techniques have been introduced on privacy preserving issues in information security by using cryptography, steganography and their combination. In this paper we proposed an effective and efficient approach based on cryptography and Chains Matrix Multiplication (CMM) steganography uses optimal substructure property for generating random key to hide the data. It has to be improved privacy of sensitive data in information security analysis.

The signcryption scheme is a primitive in public key cryptography and it is useful where privacy and authenticity are required simultaneously. Our proposed Elliptic Curve Cryptography (ECC) based signcryption scheme preserves all the basic security features with lower overheads like authentication, confidentiality, non-repudiation, unforgeability, forward secrecy as well as public verifiability feature. We have showed through formal security analysis that our proposed scheme is secured against any adversary. The proposed scheme has been implemented in AVISPA, a well-known formal verification tool and the simulation results show that the proposed scheme is secured against any intruder attack.

This paper proposes a new universal steganalysis method based on contourlet transform with high detection rate. An important aspect of this paper is that it uses the minimum number of features in the transform domain and gives a better accuracy than many of the existing steganalysis methods. Only five features have been extracted from the contourlet transformed image and a back propagation neural network classifier has been used to classify whether the given image is stego image or cover. The efficiency of the proposed method is demonstrated through experimental results. Also its performance is compared with the state of the art wavelet based steganalyzer (WBS), Feature based steganalyzer (FBS) and Contourlet based steganalyzer (CBS). The results show significantly high performance of our method.

The k-Means clustering algorithm partition a dataset into meaningful patterns. Intrusion Detection System detects malicious attacks which generally include theft information. It can be found from the studies that clustering based intrusion detection methods may be helpful in detecting unknown attack patterns compared to traditional intrusion detection systems. This paper presents modified k-Means by applying preprocessing and normalization steps. As a result the effectiveness is improved and it overcomes the shortcomings of k-Means. This approach is proposed to work on network intrusion data and the algorithm is experimented with KDD99 dataset and found satisfactory results.

This paper presents a novel Steganographic technique of color image authentication technique based on the Discrete two dimensional Z-Transform using Quantization Index Modulation (QIM). The Z-Transform is applied on sub-image block of size 2 x 2 in row major order of the carrier image for frequency components of the corresponding spatial components. Image authentication is done by hiding secret message/image into the real part of the frequency component of the carrier image. A single bit of secret message/image is embedded in each carrier image byte based on Quantization Index Modulation where a tolerance factor Δ has been used for invisible embedding. After embedding, a delicate re-adjusting phase is applied in all the frequency components of each mask, to keep the pixel values positive and non-fractional in the spatial domain. It is also applicable for secrete data transmission through carrier color image by hiding secrete data. Experimental results proof the robustness and performance of the proposed technique.

Embedding message into audio signal especially within songs without compromising its audible quality is one of the growing research areas. The techniques are used for different purposes in practical life. Various methods are evolved for hiding information into audio signals and quality is maintained only by calculating the acceptance ratio of embedding data using human perception. Therefore, an efficient way of finding the limit of embedding information in song signal is one of the challenging issues. In this paper, using modulation of channel capacity in modified form is used to determine the embedded data and song signal trade-off ratio for getting future guideline embedding information in song signal with correlation among embedded data is fabricated. A comparative study has been made with similar existing techniques for performance analysis and experimental results are also supported with mathematical formula based on Microsoft WAVE (".wav") stereo sound file.

In this paper, a novel two-dimensional Discrete Fourier Transformation based information embedding has been proposed for color image authentication (DFTIECIA). The DFT is applied on each 2 x 2 sub-image block of the carrier image. Based on channel and the absolute difference value of four most significant bits of the second frequency component in row major order, at most four bits are embedded in the LSB part of second, third and fourth frequency component based on the varying perceptibility of human eye for three channels viz. red, green and blue. The first component is used as indicator for further re-adjustment, if necessary. Inverse DFT (IDFT) is applied on each 2 x 2 mask after embedding to generate stego image. Experimental results conform that the proposed algorithm performs better than the Discrete Cosine Transform (DCT), Quaternion Fourier Transformation (QFT) and Spatio Chromatic DFT (SCDFT) based schemes.

Distributed denial-of-service (DDoS) is a very powerful attack on Internet resources as well as system resources. Hence, it is imperative to detect these attacks in real time else the impact will be irresistible.In this work we propose a new method of applying cumulative sum (CUSUM) algorithm to track variations of the attack characteristic variable X(n) from the observed traffic (specific to different kinds of attacks) and raise an alarm based on threshold. But often a threshold based mechanism produces many false alarms. Adaptive Neuro Fuzzy Inference System (ANFIS) which is capable of removing the abrupt separation between normality and abnormality as well as appropriately select the membership function parameters has been used for detection of attacks based on CUSUM values. The detection mechanism is well corroborated by experimental results.

The security of digital images has become increasingly more important in today’s highly computerized and interconnected world. In this work a new image encryption technique is proposed which is based on genetic algorithm. The method comprises three stages. The first stage is selection of key sequence. Linear congruential pseudo random generator is used for key sequence generation. The crossover operation is performed in the second stage. In third stage, mutation operation is performed on the result obtained from the previous stage. The proposed method combines both transposition and substitution techniques to secure the data. The results obtained are analyzed through histograms. Performance of the proposed algorithm is measured in terms of correlation coefficient. The analysis carried out reveals that the proposed algorithm works successfully for all types of images.

Semantically image has very meaningful categories. Classifying image using the low level feature is a challenging task. So far several methods has been used for automated machine learning in semantic image classification in this paper we have proposed a new and far more efficient method for semantic image classification using normalized vectors of WFSVM(weighted feature support vector machine). For image classification, the image data usually have a large data set on number of feature dimensions. Traditional image classification algorithms based on the SVM assign normalized automated weights to these features. The relevant and non relevant features of image are separated using these normalized vectors. Using normalized vector the efficiency and training time of SVM is improved to a greater extent. In this paper we proposed an approach to use weighted normalized vectors in place of normalized vectors. The Experiment is carried out on 256_categories database and result in better. The weighted normalization of vector has two advantages than the traditional SVM: the better performance of generalization ability and less training time.

The cryptographic hash function Grøstl is one of the five finalists of SHA-3 competition organized by US National Institute of Standards and Technology (NIST). In this paper we propose a modified Grøstl-256 hash algorithm, which is 1.2 times faster than Grøstl-256 and as secure as Grostl-256. We further show that the modified Grøstl performs equally well as the original one when compared against standard metrics that are used to evaluate hash functions. A prototype tool developed to compare and evaluate the modified and the original Grostl-256 algorithm has been used for this purpose.

Reliable user authentication is becoming an increasingly important task. Biometric based authentication offers several advantages over other authentication methods. Iris based biometric authentication gained more popularity because of its greater accuracy and uniqueness. In this paper, a new method is proposed based on Haar transform and Majority Voting to improve the overall efficiency of existing iris recognition systems in terms of accuracy and storage space. An existing iris recognition algorithm proposed by Libor Masek is used to generate an iris template. Haar transform is applied on those templates to reduce the storage space. Majority voting technique is being performed with target class iriscodes to improve the accuracy of the recognition system. Iriscodes of various combinations are made using different levels of haar decomposition and each combination is represented as a method. Experiments on well known CASIA iris database show that the proposed technique is more efficient and promising.

Advanced internet technologies providing services like e-mail, social networking, online banking, online shopping etc., have made day-to-day activities simple and convenient. Increasing dependency on the internet, convenience, and decreasing cost of electronic devices have resulted in frequent use of online services. However, increased indulgence in the internet by people has also accelerated the pace of digital crimes. The increase in number and complexity of digital crime cases has caught the attention of forensic investigators. The Digital Investigators are faced with the challenge of gathering accurate digital evidence from as many sources as possible. In this paper, an attempt was made to recover digital evidence from a system’s RAM in the form of information about the most recent browsing session of the user. Four different applications were chosen for the experiment and it was found that crucial information about the target user such as, user name, passwords, etc., was recoverable.

This paper proposes a method for face detection and recognition using Modified Hidden Markov Model (HMM) and Support Vector Machine (SVM). It is a two layer architecture system that identifies all image regions which contain face or non-face. At the first stage, the Kernel HMM classifies input pattern into three classes: a face class, undecided class or non-face class. In the final stage, SVM detects the face class or non-face class if any sub-image falsely judged as undecided class. This system alleviates the problem of false positive rate. The experimental result shows that the proposed approach outperforms some of the existing face detection methods and we have compared various face detection method.

A blind high capacity lossless semi-fragile audio watermarking algorithm based on the statistical quantity related to the correlation among the audio sample values is proposed. Time domain embedding is used to reduce the computational time in searching the synchronization codes. The watermark is embedded into the non-silent high energy frames (HEF) to take advantage of the perceptual properties of the Human Auditory System (HAS) and to improve the transparency of the digital watermark. The Offset value used for embedding is made adaptive to the required SNR for the final watermarked audio signal. The watermark can be removed using a secret watermarking key with only minimal remaining distortion. The method proposed is media format independent and it can be used with lossy compression. Both subjective and objective tests reveal that the proposed watermarking scheme maintains high audio quality and is simultaneously highly robust to pirate attacks, including MP3 compression, cropping, time shifting, filtering, re-sampling, and re-quantization., and re-quantization.

Without physical boundaries, a wireless network faces many more vulnerabilities than a wired network does. Compared to Wi-Fi, security has been included in the design of WiMAX systems at the very start. IEEE802.16 standard (WiMAX) provides a security sublayer in the MAC layer to address the privacy issues across the fixed BWA (Broadband Wireless Access). After the launch of this new standard, a number of security issues were reported in several articles. Ever since the beginning, work has been in progress for the neutralization of these identified threats.

In this paper, we first overview the IEEE802.16 standard, especially the security sublayer, and then authorization protocol PKM in WiMAX has been analyzed. We found that PKM (Privacy and Key Management) is vulnerable to replay, DoS, Man-in-the middle attacks and we propose a new methodology to prevent the authorization protocol from such attacks.

We also give a formal analysis of authentication protocol (PKMv2) and for the proposed protocol; we conclude that our proposition prevent the attacks like Denial of service (DOS), Man-in-the-middle and replay. The formal analysis has been conducted using a specialized model checker Scyther, which provides formal proofs of the security protocol.

In this paper a novel steganographic technique based on Discrete Cosine Transform (DCT) is demonstrated for image authentication in frequency domain. The transformation is implemented on sub-image block called mask of size 2 x 2 of spatial components in row major order for the entire image. Single bit of authenticating secret message/image is fabricated in the real part of the frequency component of 2

nd

and 3

rd

carrier image byte of each sub-image block. A minor re-adjustment is incorporated only in the first component of each sub image block after embedding to keep the pixel values positive and non fractional in spatial domain. Robustness is achieved through embedding secret bits in variable positions of the carrier image byte determined by random function and subsequent masking. Experimental results depict enhanced performance of the proposed watermarking technique.

In emerging technology of Internet, security issues are becoming more challenging. In case of wired LAN it is somewhat in control, but in case of wireless networks due to exponential growth in attacks, it has made difficult to detect such security loopholes. Wireless network security is being addressed using firewalls, encryption techniques and wired IDS (Intrusion Detection System) methods. But the approaches which were used in wired network were not successful in producing effective results for wireless networks. It is so because of features of wireless network such as open medium, dynamic changing topology, cooperative algorithms, lack of centralized monitoring and management point, and lack of a clear line of defense etc. So, there is need for new approach which will efficiently detect intrusion in wireless network. Efficiency can be achieved by implementing distributive, co-operative based, multi-agent IDS. The proposed system supports all these three features. It includes mobile agents for intrusion detection which uses SNMP (Simple network Management Protocol) and MIB (Management Information Base) variables for mobile wireless networks.

Nodes are replicated in fault-tolerant networks not only to increase the aggregate decision reliability but also to survive the failure of a subset of those nodes. A simple majority rule is the most common aggregate decision rule. One may believe that a simple majority rule may not be optimal when node replication is performed in organization following a hierarchical structure like a corporation or a military command. This research shows that if the node’s observations are better than random, then a simple majority rule is better than a hierarchical decision. Moreover, even though there are a few compromised nodes that falsify their vote, a simple majority rule will still be superior. However, a hierarchical decision process is more scalable and the vote can be aggregated faster. This paper also proposed a technique based on the law of diminishing marginal utility to calculate the optimum number of nodes in a decision process.

This work is modified work of Anil kumar and Navin Rajgopal, where they have considered that dealer encrypts the secret and share the secret with 2 participants. Only the dealer can encrypt and decrypt the secret. Even the sharing and reconstruction of secret is performed by only the dealer. Due to this no other user will be able to reconstruct the secret. There are few drawbacks in this method. This works with only 2 participants as the second image is dependent on the first share and the image. For reconstruction both the shares are must. The dealer encrypts and decrypts the secret which takes more time. No other participants can reconstruct the secret even though they have the secret.

We have considered this work and made some changes so that no encryption decryptions are performed. The secret can be shared among any number of participants, and a few shares are sufficient to reconstruct the secret. The reconstruction can be done by any participant unlike the work mentioned above, where only the dealer can reconstruct the secret. We are also considering the images to cover the secret shares based on the pseudo random numbers, but this is different from the way the numbers are used in the above method.

Security is an age long dream in all the walks of our social life. In software industry, security is regarded as wheels on which the entire system can move smoothly. Various tools/techniques have been deployed for developing secure software, but, on the other hand, attackers are continuously exploiting vulnerabilities to compromise security. Firewalls, intrusion prevention/detection and antivirus systems cannot simply solve this problem to the desirable extent. Only a rigorous effort by the software development community for building more secure software can foil attackers and allow users to feel protected from such exploitations. Research studies reveal that security cannot be added in developed software rather it should be introduced

right from the beginning

in the SDLC. To achieve this objective, security measures must be embedded throughout the SDLC phases and starting from the requirements phase itself. Non-Repudiation requirement is globally accepted as one of the prominent security requirements. Appropriate level of non-repudiation may well enforce security features and hence, ensure security for deployed software. A checklist is proposed, in this paper, which may enable assessment of the appropriateness of non-repudiation requirements and lead to counter/additional measures for security assurance.

The one dimensional (1D) barcode was developed as a package label that could be swiftly and accurately read by a laser scanner. It has become ubiquitous, with symbologies such as UPC used to label approximately 99% of all packaged goods in the US [1]. The two-dimensional (2D) barcode has improved the information encoded capacity, and it also has enriched the applications of barcode technique. Recently, there are researches dealing with watermark technique on barcode to prevent it from counterfeited or prepensely tampered. The existent methods still have to limit the size of embedded watermark in a relatively small portion. Furthermore, it also needs to utilize original watermark or other auxiliary verification mechanism to achieve the barcode verification. In this paper, we propose a novel watermarking barcode reading enhancement method. The proposed method can fight most of reading challenges of watermarking barcode. Experiments with challenging barcode images show substantial improvement over other state-of-the-art algorithms.

Video Frame quality and statistical undetectability are two key issues related to steganography techniques. In this paper, we propose a novel flash video file (.flv file extension) information-embedding scheme in which the embedded information is reconstructed without knowing the original host flash video file. The proposed method presents high rate of information embedding and is robust to lossless and lossy compression. The characteristic of the proposed scheme is to use a weak point in the header information of flash video file to assist compression process. Experimental results have indicated that the method is robust against lossless and lossy compression.

Wireless Mesh Networks (WMNs) have emerging application because of its ad-hoc features, high internet bandwidth capability, and interoperable with various networks. However, all features of WMNs vulnerable due to their inadequate security services, and most of the existing techniques protect WMNs only.from single adversary node, but these techniques are failed to protect against multiple colluding attacks, and also have same reputation value for all types of attacks. To overcome these problems for future solutions, we have done clear analytical survey on network layer attacks. Eventually, we have come up with taxonomy of network layer attack.

In IT era, every organization is depends on computer and internet for its daily routine works. A major objective of an information security policy is to ensure that information is always available to support critical business processing. This is a great challenge to develop secure software to meet its requirements and to satisfy security requirements i.e. Confidentiality, Integrity, and Availability (CIA) against identified risks. To prevent sensitive data, creating session mechanism is used which is helpful in reducing denial of service attack. In this paper, a methodology has been proposed and validated to assess the availability risk at design level using methods and classes.

This paper presents a tool for the analysis, and simulation of direction-of-arrival estimation in wireless mobile communication systems over the Rayleigh fading channel. It reviews three subspace based methods of Direction of arrival estimation algorithms. The standard Multiple Signal Classification (MUSIC) can be obtained from the subspace based methods. In improved MUSIC procedure called Cyclic MUSIC, it can automatically classify the signals as desired and undesired based on the known spectral correlation property and estimate only the desired signal’s DOA. The next method is an extension of the Cyclic MUSIC algorithm called Extended Cyclic MUSIC by using an extended array data vector. By exploiting cyclostationarity, the signal’s DOA estimation can be significantly improved. In this paper, the DOA estimation algorithm using the de-noising pre-processing based on time-frequency conversion analysis is proposed, and the performances are analyzed. This is focused on the improvement of DOA estimation at a lower SNR and interference environment. This paper provides a fairly complete image of the performance and statistical efficiency of each of above three methods with QPSK signal model for coherent system.

Scheduling is absolutely the resource management. A group of interdependent jobs/tasks forms the workflow application and scheduling is to map the jobs/tasks on to the collection of heterogeneous resources available in a massive geographic spread. Most complicated applications consist of interdependent jobs that coordinate to solve a problem. The completion of a particular job is the criterion function essentially to meet in order to start the execution of those jobs that depend upon it [1]. This kind of workflow application may be represented in the form of a Directed Acyclic Graph (DAG). Grid Workflow is such an application and is modeled by DAG. This paper proposes a tool that generates Directed Acyclic Graph through Randomizer, which helps in solving the scheduling problem among the dependent tasks by considering the parameters, computation cost (COMPCost) of the nodes and the communication cost (COMMCost) between the nodes. This tool is developed in Java, considering it as a platform independent and web authoring application developer. The task dependencies are made random, the computation cost and communication cost are also randomly allocated by the randomizer. The output generated by the tool includes (i) a visual component of an actual DAG,(ii) a table with complete information on task, its predecessors, COMPCost, COMMCost and (iii) detailed description about the number of levels, number of tasks at each level, identification of a tasks in a level and relationship between the nodes.

Parallel processing system (PPS) provides high communication speed and utilization of resources to the information processing system. In order to attain an effective PPS, Multistage Interconnection Network (MIN) is used. Designing a fault tolerant and cost effective MIN is a major key issue. This paper presents a new fault tolerant irregular MIN named as Advance Irregular Alpha Multistage Interconnection Network (AIAMIN). The proposed MIN is the advance form of modified alpha network (ALN). It has been analyzed that the proposed AIAMIN yields better fault tolerance by providing more alternate path between any pair of source and destination address, as compare to the existing modified ALN.

To study the Energy Efficiency (

EE

) of cloud database so as to achieve green computing, the measurement model and approach of

EE

should be defined, the

EE

characteristics of cloud database should be investigated, and the

EE

of cloud database should be compared with that of parallel database. In this paper, the measurement model of

EE

and its mathematical expression are proposed; the test cases including data loading, querying and analyzing are defined; the measurement approach of cloud database’s

EE

is described; the

EE

characteristics of HBase (a cloud database) when executing loading, retrieving, querying, aggregation and join operations are analyzed and compared with that of GridSQL (a parallel database). Plenty of experiments show that, despite that cloud database is an application of “green cloud computing”, the

EE

of HBase remains to be further optimized.

This Paper describes Traffic Maintenance System as a Grid System and proposes an approach for reducing congestion on road traffic. It introduces terminology, notations and evolves congestion controlling strategy. The steps used in this strategy such as clustering, scheduling and communication are described with an illustrative example.

Grid Computing is information technology which used to share resources across the global to solve the large scale problem. It is based on networks to enable large scale aggregation and sharing of computational, data, sensors and other resources across global. Grid Computing Environment provides the services like Job Executing Environment and web services as well. So Grid Computing Environment should be secured from the outside and inside intruder. Grid Computing is a Global Infrastructure on the internet has led to a security attacks on the Computing Infrastructure. The wide varieties of IDS (Intrusion Detection System) are available which are designed to handle the specific types of attacks. No technique can give QoS along with IDS. So this paper proposes a Mobile Agent-based Intrusion Detection System (MA-IDS) architecture, is a secured architecture to provide the security, maximizing the user’s benefits and Quality of Service (QoS). The Most Benefit Travelling Salesman Problem (MBTSP) is introduced to describe how the Agent acts in this model by using optimized routing algorithm.

The adaptability in software is the main fascinating concern for which most of the software architects today are really interested in providing the Autonomic computing. In order to provide remedy for the service failures that occurs at the servers of the respective service providers, there is a need to introduce the self-reconfiguration planes to be applied astronomically without the interruption of the administrator to solve the problem manually. Different programming models have been introduced for providing the dynamic behavior of the services being provided. Few among them are the Aspect Oriented Programming (AOP) and Feature Oriented Programming (FOP) both of them having the ability to modularize the crosscutting concerns, where the former is dependent on aspects, advice and lateral one on the collaboration design and refinements. In this paper we will use the design patterns which will satisfy the properties of autonomic computing system: for the Decision-Making phase we will introduce Case-Based Reasoning design pattern, and for Reconfiguration phase we will introduce Reactor design pattern. The most important proposal in our design pattern is that we will use the Association Rule Learning method of Data Mining to learn about new services that can be added along with the requested service to make the service as a dynamic composition of two or more services. Then we will include the new service as an aspectual feature module code without interrupting the user. The pattern is described using a java-like notation for the classes and interfaces. A simple UML and Sequence diagram are depicted.

Vehicular Ad-hoc Networks (VANET) are a special kind of Mobile Ad-hoc network (MANET), in which vehicles on the road forms the nodes of the networks. Now a days, VANETs find several applications as an Intelligent Transportation System. Dynamic network architectures and node movement characteristics differentiates VANETs from other kinds of ad hoc networks. Since VANETs have a dynamic network topology, routing in VANETs are complicated. Ad-hoc On-Demand Distance Vector (AODV) routing protocol is the most commonly used topology based routing protocol for VANET. During the route discovery process AODV broadcasts route request message (RREQ). It creates many unused routes between a source and a destination node. This paper aims at improving the performance of AODV by enhancing the existing protocol by creating stable clusters and performing routing by Cluster Heads and Gateway nodes.

In this paper, we proposed a new model for recognizing various emotions of humans with different age groups and gender. Fuzzy is used for extracting more accurate region of interest, i.e., face. The dimensionality of face image is reduced by the Principal Component Analysis (PCA) [12] and finally emotion is recognized and classified using Euclidean Distance. Database is prepared and some performance metrics like recognition-rate v/s Eigen-range has been calculated. The proposed method was also tested on FACES Collection database [13]. The experiment results demonstrate that the emotion recognition system has been successful with average recognition rate of 96.66% (with both experiment databases) when approximately or more than 60% eigenfaces used. It is also shown that database can be easily expanded to classify faces and non faces images.

The number of processing cores within computing nodes which are used in current clustered systems, are growing up rapidly. Despite this trend, the number of available network interfaces in such nodes almost has been remained unchanged. This issue can lead to high usage of network interface in many workloads, especially in workloads which have high inter-process communications. As a result, network interface would become a performance bottleneck and can degrade the performance drastically. The goal of this paper is to introduce a new process mapping algorithm in multi-core clusters aimed to reducing network interface contention and improving the performance of running parallel applications. Comparison of the new algorithm with other well-known methods in synthetic and real workloads indicates that the new strategy can gain 5% to 90% performance improvement in heavy communicating workloads.

Peer to peer (P2P) grid system has good potential for decentralized grid scheduling. The existing P2P grid resource management algorithms allow detection of resources after generation of task. Recently, few new P2P grid resource management schemes proposed discovery of resources before task is generated. These schemes simply shortlist best possible subset of grid resources on basis of one or many overlays. In this paper, we suggest that these algorithms have potential to include the step of organizing shortlisted resources in non-increasing order on basis of optimization criteria. Addition of this step will reduce time to find out schedule of DAG’s interdependent tasks on fully decentralized P2P grid. An optimization criterion is based on computation capability and communication cost of grid resources.

This paper introduces an overview of Web-based GIS and its applications and some of the easily assessable Desktop Open Source GIS Software with easy–to–follow guidance that will help water resource decision-maker and interested stakeholder. Web-based GIS is a prospective application in GIS and represents an important advancement over the traditional desktop GIS. Its application eliminates duplication and inconsistency (which is often possible between GIS professionals) and makes location information conveniently and intuitively accessible across organization/s, at a lower cost per user. Internet provides a medium for processing geo-related information and spatial information to users at an amount larger than traditional GIS. XML and Java have been developed to facilitate the utilization of the internet as well as to provide a coding standard in the software industry. Therefore, in the last few years, there has been a significant development in the area of free and open source GIS software. This paradigm shift from stand-alone GIS to open access Web GIS services provide greater opportunities for sustainable solutions in water resource management and planning.

Adaptability in software is the main fascinating concern for which today’s software architects are really interested in providing the autonomic computing. Different programming paradigms have been introduced for enhancing the dynamic behavior of the programs. Few among them are the Aspect oriented programming (AOP) and Feature oriented programming (FOP) with both of them having the ability to modularize the crosscutting concerns, where the former is dependent on aspects ,advice and lateral one on the collaboration design and refinements. In order to provide remedy for the service failures that occurs at the servers of the respective service providers, there is a need to introduce the self-reconfiguration planes to be applied autonomically without the interruption of the administrator to solve the problem manually. In this paper we will Propose an Service Injection Design Pattern for Unstructured Peer-to-Peer networks, which is designed with Aspect-oriented design patterns .We propose this pattern which is an amalgamation of the Strategy Design Pattern, Worker Object Aspect-Oriented Design Pattern, and Check-List Design Pattern these can be used to design the Self-Adaptive Systems. The main concept here is that when a client requests for a complex service then Service Composition should be down to fulfill the request. With the help of strategy pattern we can choose a service that can do the task of two or more services at a single click. With the Web Service Description Language (WSDL) which is an XML file that can be requested from all the Web Services providing peers (as HTTP GET). This file contains the all the description about the service, means the input and output parameters of that service and its location details. When a client requests for a service that is not loaded currently in the memory will be injected as Aspectual Feature Module code. Here we will be using the Service Oriented Architecture (SOA) with Web Services in Java to Implement the Design Pattern. The pattern is described using a java-like notation for the classes and interfaces. A simple UML class and Sequence diagrams are depicted.

Services might be moved, or relocated and may undergo changes during its life cycle but compromising the changes with respect to the business policy will be the key issue which has not been addressed by the existing business process change management framework. Hence there should be an effective framework for managing these changes without affecting the business functionality and also ensuring the associated business policy. This paper stresses mainly on handling these emergency changes to a business process which is capsuled as web services dynamically at the business analyst level. We use Finite State Machine for simulating the business logic set which includes the business policy constraints with its associated mapping function in order ensure the changes made are policy enabled during run time. It also facilitates Business Analyst directly to control and manage the business logic of the targeting web services dynamically and thereby eliminates the IT staff effort.