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Über dieses Buch

This comprehensive guide exposes the security risks and vulnerabilities of computer networks and networked devices, offering advice on developing improved algorithms and best practices for enhancing system security. Fully revised and updated, this new edition embraces a broader view of computer networks that encompasses agile mobile systems and social networks. Features: provides supporting material for lecturers and students, including an instructor’s manual, slides, solutions, and laboratory materials; includes both quick and more thought-provoking exercises at the end of each chapter; devotes an entire chapter to laboratory exercises; discusses flaws and vulnerabilities in computer network infrastructures and protocols; proposes practical and efficient solutions to security issues; explores the role of legislation, regulation, and law enforcement in maintaining computer and computer network security; examines the impact of developments in virtualization, cloud computing, and mobile systems.

Inhaltsverzeichnis

Frontmatter

Understanding the Traditional Computer Network Security

1. Computer Network Fundamentals

Abstract
The basic ideas in all types of communication are that there must be three ingredients for the communication to be effective. First, there must be two entities, dubbed a sender and a receiver. These two must have something they need to share. Second, there must be a medium through which the sharable item is channeled. This is the transmission medium. Finally, there must be an agreed-on set of communication rules or protocols. These three apply to every category or structure of communication.
Joseph Migga Kizza

2. Understanding Computer Network Security

Abstract
Before we talk about network security, we need to understand in general terms what security is. Security is a continuous process of protecting an object from unauthorized access. It is as state of being or feeling protected from harm. That object in that state may be a person, an organization such as a business, or property such as a computer system or a file. Security comes from secure which means, according to Webster Dictionary, a state of being free from care, anxiety, or fear [1].
Joseph Migga Kizza

Security Challenges to the Traditional Computer Networks

3. Security Threats to Computer Networks

Abstract
In February, 2002, the Internet security watch group CERT Coordination Center first disclosed to the global audience that global networks, including the Internet, phone systems, and the electrical power grid, are vulnerable to attack because of weakness in programming in a small but key network component. The component, an Abstract Syntax Notation One, or ASN.1, is a communication protocol used widely in the Simple Network Management Protocol (SNMP).
Joseph Migga Kizza

4. Computer Network Vulnerabilities

Abstract
System vulnerabilities are weaknesses in the software or hardware on a server or a client that can be exploited by a determined intruder to gain access to or shut down a network. Donald Pipkin defines system vulnerability as a condition, a weakness of or an absence of security procedure or technical, physical, or other controls that could be exploited by a threat [1].
Joseph Migga Kizza

5. Cyber Crimes and Hackers

Abstract
The greatest threats to the security, privacy, and reliability of computer networks and other related information systems in general are cyber crimes committed by cyber criminals, but most importantly hackers. Judging by the damage caused by past cyber criminal and hacker attacks to computer networks in businesses, governments, and individuals, resulting in inconvenience and loss of productivity and credibility, one cannot fail to see that there is a growing community demand to software and hardware companies to create more secure products that can be used to identify threats and vulnerabilities, to fix problems, and to deliver security solutions.
Joseph Migga Kizza

6. Hostile Scripts

Abstract
The rapid growth of the Internet and its ability to offer services have made it the fastest growing medium of communication today. Today’s and tomorrow’s business transactions involving financial data; product development and marketing; storage of sensitive company information; and the creation, dissemination, sharing, and storing of information are and will continue to be made online, most specifically on the Web. The automation and dynamic growth of an interactive Web have created a huge demand for a new type of Web programming to meet the growing demand of millions of Web services from users around the world. Some services and requests are tedious, and others are complex, yet the rate of growth of the number of requests, the amount of services requested in terms of bandwidth, and the quality of information requested warrant a technology to automate the process. Script technology came in timely to the rescue. Scripting is a powerful automation technology on the Internet that makes the Web highly interactive.
Joseph Migga Kizza

7. Security Assessment, Analysis, and Assurance

Abstract
The rapid development in both computer and telecommunication technologies has resulted in massive interconnectivity and interoperability of systems. The world is getting more and more interconnected every day. Most major organization systems are interconnected to other systems through networks. The bigger the networks, the bigger the security problems involving the system resources on these networks. Many companies, businesses, and institutions whose systems work in coordination and collaboration with other systems as they share each others’ resources and communicate with each other face a constant security threat to these systems, yet the collaboration must go on.
Joseph Migga Kizza

Dealing with Network Security Challenges

Frontmatter

8. Disaster Management

Abstract
Webster’s Dictionary defines disaster as a sudden misfortune, a catastrophe that affects society [1]. It is the effect of a hazardous event caused by either man or nature. Man-made disasters are those disasters that involve a human element like intent, error, or negligence. Natural disasters are those caused by the forces of nature like hurricanes, tornados, and tsunamis. Disasters, natural or man-made, may cause great devastation to society and the environment. For example, the 2006 tsunami in Southeast Asia caused both huge human losses and environment destruction. The effects of a disaster may be short lived or long lasting. Most disasters, both man-made and natural, have long lasting effects. To mitigate disaster effects on society and businesses, disaster management skills are needed.
Joseph Migga Kizza

9. Access Control and Authorization

Abstract
One of the system administrator’s biggest problems, which can soon turn into a nightmare if it is not well handled, is controlling access of who gets in and what is taken out of the system and who uses what resources, when, and in what amounts. Access control is restricting this access to a system or system resources based on something other than the identity of the user. For example, we can allow or deny access to a system’s resources based on the name or address of the machine requesting a document.
Joseph Migga Kizza

10. Authentication

Abstract
Authentication is the process of validating the identity of someone or something. It uses information provided to the authenticator to determine whether someone or something is in fact who or what it is declared to be. In private and public computing systems, for example, in computer networks, the process of authentication commonly involves someone, usually the user, using a password provided by the system administrator to logon. The user’s possession of a password is meant to guarantee that the user is authentic. It means that at some previous time, the user requested, from the system administrator, and the administrator assigned and/or registered a self-selected password.
Joseph Migga Kizza

11. Cryptography

Abstract
So much has been said, and so much has been gained; thousands of lives have been lost, and empires have fallen because a secret was not kept. Efforts to keep secrets have been made by humans probably since the beginning of humanity itself. Long ago, humans discovered the essence of secrecy. The art of keeping secrets resulted in victories in wars and in growth of mighty empires. Powerful rulers learned to keep secrets and pass information without interception; that was the beginning of cryptography. Although the basic concepts of cryptography predate the Greeks, the present word cryptography, used to describe the art of secret communication, comes from the Greek meaning “secret writing.” From its rather simple beginnings, cryptography has grown in tandem with technology, and its importance has also similarly grown. Just as in its early days, good cryptographic prowess still wins wars.
Joseph Migga Kizza

12. Firewalls

Abstract
The rapid growth of the Internet has led to a corresponding growth of both users and activities in cyberspace. Unfortunately, not all these users and their activities are reputable; thus, the Internet has been increasingly, at least to many individuals and businesses, turning into a “bad Internet.” Bad people are plowing the Internet with evil activities that include, among other things, intrusion into company and individual systems looking for company data and individual information that erodes privacy and security. There has, therefore, been a need to protect company systems, and now individual PCs, keeping them out of access from those “bad users” out on the “bad Internet.” As companies build private networks and decide to connect them onto the Internet, network security becomes one of the most important concerns network system administrators face. In fact, these network administrators are facing threats from two fronts: the external Internet and the internal users within the company network. So network system administrators must be able to find ways to restrict access to the company network or sections of the network from both the “bad Internet” outside and from unscrupulous inside users.
Joseph Migga Kizza

13. System Intrusion Detection and Prevention

Abstract
The psychology and politics of ownership have historically dictated that individuals and groups tend to protect valuable resources. This grew out of the fact that once a resource has been judged to have value, no matter how much protection given to it, there is always a potential that the security provided for the resource will at some point fail. This notion has driven the concept of system security and defined the disciplines of computer and computer network security. Computer network security is made up of three principles: prevention, detection, and response. Although these three are fundamental ingredients of security, most resources have been devoted to detection and prevention because if we are able to detect all security threats and prevent them, then there is no need for response.
Joseph Migga Kizza

14. Computer and Network Forensics

Abstract
The proliferation of computer technology, including wireless technology and telecommunication, the plummeting prices of these technologies, the miniaturization of computing and telecommunication devices, and globalization forces have all together contributed to our ever growing dependence on computer technology. This growing dependence has been a bonanza to computer criminals who have seen this as the best medium to carry out their missions. In fact, Richard Rubin [1] has called this new environment a tempting environment to cyber criminals, and he gives seven compelling reasons that cause such temptations. They are as follows:
Joseph Migga Kizza

15. Virus and Content Filtering

Abstract
As the size of global computer networks expands and the use of the Internet skyrockets, the security issues do manifest themselves not only in the security of computer networks but also in individual user security on individual PCs connected to the Internet either via an organization’s gateway or an Internet service provider (ISP). The security of every user, therefore, is paramount whether the user is a member of an organization network or a user of a home PC via an independent ISP. In either case, the effort is focused on protecting not only the data but also the user.
Joseph Migga Kizza

16. Standardization and Security Criteria: Security Evaluation of Computer Products

Abstract
The rapid growth of information technology (IT), our growing dependence on it, and the corresponding skyrocketing security problems arising from it have all created a high demand for comprehensive security mechanisms and best practices to mitigate these security problems. Solutions on two fronts are sought for. First well-implemented mechanisms and best practices are needed for fundamental security issues like cryptography, authentication, access control, and audit. Second, comprehensive security mechanisms are also needed for all security products so that consumers are assured of products and systems that meet their business security needs. The response to this high demand for security products has been an avalanche of products of all types, capabilities, varying price range, effectiveness, and quality. You name a product and you get a flood from vendors. As the marketplace for security products get saturated, competing product vendors and manufacturers started making all sorts of claims about their products in order to gain a market niche. In this kind of environment then, how can a customer shop for the right secure product, what security measures should be used, and how does one evaluate the security claims made by the vendors? Along the way, making a choice of a good effective security product for your system or business has become a new security problem we want to focus on in this chapter.
Joseph Migga Kizza

17. Computer Network Security Protocols

Abstract
The rapid growth of the Internet and corresponding Internet community has fueled a rapid growth of both individual and business communications leading to the growth of e-mail and e-commerce. In fact, studies now show that the majority of the Internet communication content is e-mail content. The direct result of this has been the growing concern and sometimes demand for security and privacy in electronic communication and e-commerce. Security and privacy are essential if individual communication is to continue and e-commerce is to thrive in cyberspace. The call for and desire for security and privacy has led to the advent of several proposals for security protocols and standards. Among these are Secure Socket Layer (SSL) and Transport Layer Security (TLS) Protocols, secure IP (IPSec), Secure HTTP (S-HTTP), secure e-mail (PGP and S/MIME), DNDSEC, SSH, and others. Before we proceed with the discussion of these and others, we want to warn the reader of the need for a firm understanding of the network protocol stack; otherwise go back and look over the material in Chap.​ 1 before continuing. We will discuss these protocols and standards within the framework of the network protocol stack as follows:
Joseph Migga Kizza

18. Security in Wireless Networks

Abstract
It is not feasible to discuss security in wireless networks without a thorough understanding of the working of wireless networks. In fact, as we first set out to teach the computer network infrastructure in Chap.​ 1 in order to teach network security, we are going, in the first parts of this chapter, to discuss the wireless network infrastructure. As was the case in Chap.​ 1, it is not easy to discuss a network infrastructure in a few paragraphs and expect a reader to feel comfortable enough to deal with the security issues based on the infrastructure. So, although we are promising the reader to be brief, our discussion of the wireless infrastructure may seem long to some readers and sometimes confusing to others. Bear with us as we dispose of the necessary theory for a good understanding of wireless security. A reader with a firm understanding of wireless infrastructure can skip Sects. 18.1, 18.2, 18.3, and 18.4.
Joseph Migga Kizza

19. Security in Sensor Networks

Abstract
The rapid development of wireless technology in the last few years has created new interest in low-cost wireless sensor networks. Wireless sensor networks (WSNs) or just sensor networks are grids or networks made of spatially distributed autonomous but cooperating tiny devices called sensors, all of which have sensing capabilities that are used to detect, monitor, and track physical or environmental conditions, such as temperature, sound, vibration, pressure, motion, or pollutants, at different locations [1]. A sensor, similar to that in Fig. 19.1, is a small device that produces a measurable response to a change in a physical condition. Sensor nodes can be independently used to measure a physical quantity and to convert it into a signal that can be read by an observer or by an instrument [1]. The network may consist of just a few or thousands of tiny, mostly immobile, usually, randomly deployed nodes, covering a small or large geographical area. In many cases, sensor networks do not require predetermined positioning when they are randomly deployed, making them viable for inaccessible terrains where they can quickly self-organize and form a network on the fly.
Joseph Migga Kizza

Elastic Extension Beyond the Traditional Computer Network: Virtualization, Cloud Computing and Mobile Systems

Frontmatter

20. Mobile Communication Systems and Related Security Issues

Abstract
In the previous two Chaps.​ 18 and 19, we dealt with wireless communication but restricted our discussion to sensor networks, wireless communication networks, and cellular networks. We discussed a good number of communication devices and their communication protocols. We also discussed the security problems, and we propose solutions in some cases. What we did not do is actually put all these devices and technologies together to create the current phenomenal mobile communication devices, and the technology is currently driving computing and communication. We are going to do this in this chapter and more. The last two decades have witnessed a revolution of sorts in communication spearheaded by the rapidly evolving technologies in both software and hardware. A mobile communication system consists of two or more of the following devices, running specifically developed software to sustain, for a period of time, a wireless communication link between them: mobile telephone, broadly construed here to include devices based on Code Division Multiple Access (CDMA), Time Division Multiple Access (TDMA), Global System for Mobile Communications (GSM), and Wireless Personal Digital Assistants (WPDA) digital technologies and follow-ons, as well as satellite telephones and e-mail appliances. Mobile communication systems are revolutionizing the world today, shrinking the world to between two or more small handheld mobile devices. The rapid changes in communication technologies, revolutionary changes in software, and the growth of large powerful communication network technologies all have eased communication and brought it to large swaths of the globe. The high-end competition between the mobile telecommunication operators resulting in plummeting device prices, the quickly developing smartphone technology, and growing number of undersea cables and cheaper satellites technologies are bringing Internet access to almost every one of the global rural poor faster than many had anticipated.
Joseph Migga Kizza

21. Virtualization Infrastructure and Related Security Issues

Abstract
Virtualization is a process through which one can create something that is there in effect and performance but in reality not there – that is virtual. It is a physical abstraction of the company computing resources like storage, network servers, and memory. VMware.com, a software developer and a global leader in the virtualization market, defines virtualization as a process in which software creates virtual machines (VMs) including a virtual machine monitor called “hypervisor,” which allocates hardware resources dynamically and transparently so that multiple operating systems, called “guest operating systems,” can run concurrently on a single physical computer without even knowing it [1]. For example, using software virtualization, one can, using the existing underlying hardware and software resources like operating systems, create and run several independent virtual operating systems on top of one physical operating system using the existing hardware resources to execute independent system tasks. Hardware virtualization also takes the same concept where several servers or client machines can be created based on one underlying hardware. The virtualization concept has been with us for some time.
Joseph Migga Kizza

22. Cloud Computing and Related Security Issues

Abstract
Cloud computing as a technology is difficult to define because it is evolving without a clear start point and no clear prediction of its future course. Even though this is the case, one can say that it is a continuous evolution of a computer network technology going beyond the client–server technology. It is a technology extending the realms of a computer network creating an environment that offers scalability, better utilization of hardware, on-demand applications and storage, and lower costs over the long run through the creation of virtual servers cloned from existing instances each offering near instantaneous increase in performance, allowing companies to react quickly and dynamically to emerging demands. The “cloud” or “cloud solution,” as the technology is commonly referred to, can either be hosted onsite by the company or off-site such as Microsoft’s SkyDrive and Samsung’s S-Cloud.
Joseph Migga Kizza

23. Other Efforts to Secure Information and Computer Networks

Abstract
The rapid advances in computer technology, the plummeting prices of information processing and indexing devices, and the development of sprawling global networks have all made the generation, collection, processing, indexing, and storage of information easy. Massive information is created, processed, and moved around on a daily basis. The value of information has skyrocketed, and information has all of a sudden become a valuable asset for individuals, businesses, and nations. The security of nations has come to depend on computer networks that very few can defend effectively. Our own individual privacy and security have come to depend on the whims of the kid next door.
Joseph Migga Kizza

Hands-on Projects

24. Projects

Abstract
This is a special chapter dealing with security projects. We have arranged the projects in three parts. Part I consists of projects that can be done on a weekly or biweekly basis. Part II consists of projects that can be done in a group or individually on a semi-semester or on a semester basis. Part III consists of projects that demand a great deal of work and may require extensive research to be done. Some of the projects in this part may fulfill a master’s or even Ph.D. degree project requirements. We have tried as much as possible throughout these projects to encourage instructors and students to use open source as much as possible. This will decouple the content of the guide from the rapidly changing proprietary software market.
Joseph Migga Kizza

Backmatter

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