A new class of Hash-Chain based key pre-distribution schemes for WSN

doi:10.1016/j.comcom.2012.09.015

Computer Communications

Volume 36, Issue 3, 1 February 2013, Pages 243-255

https://doi.org/10.1016/j.comcom.2012.09.015 Get rights and content

Abstract

In the last decade, we witness a proliferation of potential application domains of wireless sensor networks (WSN). Therefore, a host of research works have been conducted by both academic and industrial communities. Nevertheless, given the sensitivity of the potential applications that are generally tightly related to the physical world and may be human beings, a large scale deployment of WSN depends on the dependability provided by these emerging networks. Particularly, security emerges as a challenging issue in WSN because of the resource limitations. Key management is one of the required building blocks of many security services, such as confidentiality, authentication, etc. Unfortunately, public key based solutions, which provide efficient key management services in conventional networks, are unsuitable for WSN because of resource limitations. Symmetric key establishment is then one of the most suitable paradigms for securing wireless sensor networks.

In this paper, we tackle the resiliency of symmetric key pre-distribution schemes against node capture. We propose a hash-based mechanism which enhances the resiliency of key pre-distribution for WSN. Applied to any pool based key pre-distribution scheme, our solution gives birth to an enhanced scheme which is more resilient against node capture attacks. We analyze and compare our solution against the existing schemes, with respect to some important criteria such as: the network resiliency against node capture, secure connectivity coverage, storage requirement, communication overhead and computation complexity. We show through analytical analysis that our solution enhances the network resiliency without introducing any new storage or communication overheads. Moreover, we show that our solution introduces insignificant computational overhead.

Introduction

A Wireless Sensor Network (WSN) is a wireless network which is composed of a set of tiny autonomous sensor nodes with sensing, computation, and wireless communication capabilities [1]. The purpose of such networks is to collect information issued from a controlled environment or a target object and then send it to a base station usually called the sink. Because of size factor and cost considerations, wireless sensor networks suffer from resource constraints including energy, memory, computation power and communication bandwidth and range. Nowadays, wireless sensor networks are increasingly used in numerous fields such as military, medical, industrial and environmental sectors; they are more and more involved in several sensitive applications which require sophisticated security services. Due to the resource limitation, existing security solutions for conventional networks could not be used in wireless sensor networks. So, the security issues became then one of the main challenges for the resource restricted environment of WSN which requires new specific solutions.

Key management is a corner stone service for many security services such as confidentiality and authentication which are required to secure communications in wireless sensor networks. The establishment of secure links between nodes is then one of the most challenging problems in WSN. The public key based solutions, which provide efficient key management services in conventional networks, are unsuitable for wireless sensor networks because of the energy, computation and storage limitations. Some public key schemes have been implemented on real sensors [2], [3], however most researchers believe that these techniques are still too heavyweight over actual sensors’ technology because they induce an important communication and computation overhead [4]. Symmetric key establishment is then one of the most suitable paradigms for securing exchanges in WSN. Because of the lack of infrastructure in WSN, we have usually no trusted third party which can attribute pairwise secret keys to neighboring nodes, that is why key pre-distribution is the most suitable paradigm for WSN.

Many symmetric key pre-distribution schemes for wireless sensor networks have been proposed in literature [5], [6], [7], [8], [9], [10], [11], [12], [13]. We classify these schemes into two categories: deterministic schemes which ensure a total secure connectivity coverage and probabilistic schemes where secure connectivity is not guaranteed and conditioned by the existence of shared keys. In order to evaluate the performances of key pre-distribution schemes, we consider five main metrics which are: network resiliency against node capture, secure connectivity coverage, communication overhead, computation complexity and storage overhead. In this paper, we consider in particular the resiliency of symmetric key pre-distribution schemes. Existing research works which addressed the network resiliency either introduce an important storage and communication overhead or degrade the secure connectivity coverage. In contrast to these solutions, our goal is to enhance the resiliency of WSN key management schemes without introducing any new storage or communication overheads while maintaining a high secure connectivity coverage.

In this work, we propose a hash-based mechanism which can be applied to existing pool based key pre-distribution schemes to enhance the network resiliency. To achieve this goal, we introduce a new method based on one way hash chain which conceals keys in such a way that the disclosure of some keys reveals only derived versions, which cannot be used to compromise other links in the network using backward keys. We call our solution: hash-chain class of key pre-distribution schemes and denote it by HC. Our class, applied to existing key pre-distribution schemes, gives birth to new schemes which are more resilient against node capture attacks. We carried out analytical analysis to compare the efficiency of our approach against basic schemes with respect to important performance criteria: the network resiliency against node capture, the secure connectivity coverage, the communication overhead, the computation complexity and the storage overhead. The obtained results show that our solution enhances the network resiliency and reduces the fraction of compromised links up to 40% compared to existing schemes while it guarantees the same secure connectivity coverage, storage and communication performance. Moreover, we show through analytical analysis and simulations that the induced computational overhead is insignificant and that the energy consumed by hash computations in our solution is negligible.

The contributions of our work are many folds and can be summarized in the following points:

•
We review the state of the art of key management in WSN. Then, we propose a classification of symmetric key management schemes for WSN into two categories: probabilistic schemes and deterministic ones. We further refine the classification into sub-categories with respect to the underlying concepts and techniques used in key exchange and agreement.
•
We introduce a mechanism to enhance the network resiliency of key pre-distribution schemes for WSN. The proposed solution is based on lightweight hash chains and improves the resiliency of existing pool-based key pre-distribution schemes.
•
We apply our solution to two pool based key pre-distribution schemes which gives birth to enhanced schemes more resilient against node capture attacks. We analyze and compare our solution against basic schemes and show through analytical analysis that we enhance the network resiliency without introducing any new storage or communication overheads. Moreover, we show that our solution does not introduce significant computational overhead.
•
We identify a smart attack on our solution and we propose an enhanced version which alleviates the diagnosed smart attack while balancing the induced computation workload.

The remainder of this paper is organized as follows: Section 2 presents related works on key management for wireless sensor networks. We define in Section 3 the metrics used to evaluate our solution and to compare it to basic schemes. Section 4 gives a general idea of our class of pool based key pre-distribution schemes. In Section 5, we present the resilient HC (q-composite) scheme issued from the application of our mechanism to the well known probabilistic q-composite scheme, we compare the performances of the two schemes and we discuss analytical results. In Section 6, we apply our class to a deterministic scheme based on the combinatorial design which gives birth to a more resilient deterministic scheme; we also analyze and compare their performances. In Section 7, we introduce a new smart attack against our mechanism and propose an enhanced version as countermeasures against this attack. Finally, Section 8 ends up this paper with some conclusions.

Section snippets

Related works: Key management schemes for WSN

Key management problem in wireless sensor networks have been extensively studied in the literature and several solutions have been proposed. Many classifications of symmetric key management schemes can be found in [14], [15], [16]. In this work, we mainly classify symmetric schemes into two categories: probabilistic schemes and deterministic ones. In deterministic schemes, each two neighboring nodes are able to establish a direct secure link which ensures a total secure connectivity coverage.

Evaluation metrics

In this work, we consider five metrics to evaluate performances of WSN key management schemes:

Network resiliency against node capture: Due to the resource limitations in WSN, sensor nodes are usually not tamper resistant. If an adversary compromises a node, he can read all secret information from its memory. Such an attack can compromise not only adjacent links of compromised links but also external links that are independent of the compromised nodes. We define the resilience against node

Our solution: HC (x) a resilient class of hash-chain based key pre-distribution schemes

As introduced before, we consider in this work the resiliency of symmetric key pre-distribution schemes against node capture. We propose a resilient class of key pre-distribution protocols that we denote by HC (x) for hash-chain (x), where x is an existing pool based key pre-distribution protocol. This class of protocols enhances the resilience of existing schemes through a lightweight hash chaining technique that conceals the same keys pre-loaded in different sensor nodes. A preliminary work

HC (q-composite): A highly resilient q-composite scheme

In this section, we develop an enhanced resilient key management scheme by applying our solution to the q-composite scheme [6]. The proposed protocol which we denote by HC (q-composite) is more resilient against node capture as we demonstrate in the following analysis.

Before the deployment of the WSN, a large pool S of keys and their identifiers are generated off-line. Each node is preloaded with a key ring of m keys randomly selected from the key pool S. Before the deployment phase, we apply a

HC (SBIBD): A resilient combinatorial design-based key management scheme

In this section, we present an enhanced deterministic key management scheme highly resilient against node capture. The latter results from the application of our hash chain class to the Symmetric Balanced Incomplete Block Design scheme proposed by Çamtepe and Yener [12]. First, we present the basic scheme, then we explain how to apply our hash chain class to this scheme, and finally we compare the performances of the two schemes.

In [12], Çamtepe and Yener introduced the use of combinatorial

Extensions and enhancements

As shown above, the mechanism that we propose allows to enhance the resiliency of existing key pre-distribution schemes against oblivious node capture attacks. Nevertheless, the proposed scheme may incur unbalanced calculation overhead. Indeed, some nodes might hash their keys many times to deduce the shared key while others do not. Moreover, a smart attacker which captures nodes having the lowest values $(i \mod L)$ would allow a largest link compromise. In this section, we tackle these two issues

Conclusion

Asymmetric key management schemes are likely to be unsuitable for WSN because of resource limitations. Moreover, because of the lack of infrastructure in WSN, it is difficult to assume the existence of a trusted third party which can attribute pairwise secret keys to neighboring nodes. This is why symmetric key pre-distribution schemes are the most suitable paradigm for wireless sensor networks to secure exchanges.

In this paper, we presented a mechanism to enhance the network resiliency of key

Acknowledgments

This work is made as part of the Picardie regional project under reference I159C. The authors thank the Picardie regional council in France and the European Regional Development Fund (ERDF) for funding and supporting this project.

References (29)

I.F. Akyildiz et al.
Wireless sensor networks: a survey
Computer Networks
(2002)
J. Zhang et al.
Wireless sensor network key management survey and taxonomy
Journal of Network and Computer Applications
(2010)
R. Watro et al.
Tinypk: securing sensor networks with public key technology
N. Gura, A. Patel, A. Wander, H. Eberle, S.C. Shantz, Comparing elliptic curve cryptography and RSA on 8bit cpus, in:...
L. Eschenauer, V.D. Gligor, A key-management scheme for distributed sensor networks, in: ACM CCS ’02, 2002, pp....
H. Chan, A. Perrig, D. Song, Random key predistribution schemes for sensor networks, in: IEEE SP ’03,...
W. Du, J. Deng, Y. Han, S. Chen, P. Varshney, A key management scheme for wireless sensor networks using deployment...
C. Castelluccia, A. Spognardi. A robust key pre-distribution protocol for multi-phase wireless sensor networks, in:...
D. Liu, P. Ning, Establishing pairwise keys in distributed sensor networks, in: ACM CCS, 2003, pp....
Z. Yu et al.
A robust group-based key management scheme for wireless sensor networks

S. Zhu, S. Setia, S. Jajodia, Leap: efficient security mechanisms for large-scale distributed sensor networks, in: ACM...

S.A. Çamtepe et al.

Combinatorial design of key distribution mechanisms for wireless sensor networks

IEEE/ACM Transactions on Networking

(2007)

B. Maala et al.

Hero: hierarchial key management protocol for heterogeneous WSN

K. Kifayat, M. Merabti, Q. Shi, D. Llewellyn-Jones, Security in wireless sensor networks, in: Handbook of Information...

Cited by (54)

New key management scheme based on pool-hash for WSN and IoT
2023, Journal of Information Security and Applications
The Internet of Things (IoT) brings together the applications linking many devices to the Internet to make the environment more “smart”. Uses vary from the human scale, from housing (Smart Home) to that of the city (Smart Cities), transport and industry. Wireless sensor networks (WSNs), which are a sub-part of the IoT, have attracted a lot of interest over lasts years in security to ensure the integrity, the authenticity and the data confidentiality. Due to the deployment of nodes in remote areas, the solution brought to the wireless sensor network to increase the information security consists to protect the messages exchanged between nodes. In the paper, we propose a new key management protocol called the Key management scheme based on pool-hash, for the establishment of new key types. We present the modification of the proposed scheme to that of the basic scheme by detailing the different phases of key management. Modification exposes a new key pool contains original keys and other hashed admit the same identities thus new session keys transmitted between sensors nodes are defined during the discovery and path key phases. Then, we specify and formalize this protocol using a mathematical concept to model the probability of connectivity and resilience against node capture. The experimental results prove that the proposed scheme is adapted to the WSN applications in terms of connectivity and resiliency.
A secure model against mobile sink replication attacks in unattended sensor networks
2023, Computer Networks
Unattended wireless sensor networks (UWSNs), in which mobile sinks (MSs) are responsible for the data collection, and which are vulnerable to multiple attacks. For example, the adversaries can initiate MS replication attack after compromising a large number of sensor nodes (SNs). To resist such attacks, some scholars have proposed some schemes. In these schemes, it is assumed that MSs are equipped with tamper resistance hardware, so they are pre-distributed most of keys of a key pool for achieving authentication with SNs. However, in outdoor and even sensitive areas, tamper-resistant hardware is not always absolutely safe. Once MSs are compromised, networks become insecure. In this paper, we propose a secure model. The model contains three types of nodes, namely SNs, MSs, and a base station (BS). MSs are responsible for collecting the data encrypted by SNs and forwarding it to BS; BS is responsible for decrypting and analyzing the collected data. During the data collection process, an MS can collect an SN's data only after being authenticated by the SN using the pre-distribution key information. But it cannot decrypt the collected data. In this model, the adversaries can induce a new type of false data injection attack. In the attack, the replicated MSs impersonate uncompromised SNs to send false data to BS by using the compromised key information. If BS accepts a large amount of false data, it will make a wrong judgment. Analysis and simulation show that the proposed model has excellent resistance against MS replication attacks and false data injection attacks by setting appropriate parameter values.
Connectivity invariant lightweight resiliency improvement strategies for CRT-subset scheme
2022, Ad Hoc Networks
Citation Excerpt :
Even these schemes have predefined structures and are not scalable. Computational complexity of hash function based schemes [9,10,12,16,20,24,33] are slightly more than their base schemes due to computations of hash functions. As observed, our deterministic HC and 2HC variants have good connectivity (same as the base schemes [23,31]), and are highly resilient at the expense of nominal increment in memory, computational complexity, and communication overheads.
It has been found in the literature of key management for IoT devices that most of the schemes do not consider the attacking behavior of the adversary. Considering the effect of adversarial attacks on system nodes, we observe that when an adversary captures a node, it can read all the secret information from the memory of the node, resulting a partial disclosure of key pool and exposes a part of other node’s keyrings. Thereby, usage of these links that are made secure by these keys is no longer permitted. The situation worsens with the compromise of more nodes. So, it becomes important to study the robustness of a system against such attacks. In this regard, it is important to define a parameter that measures the security of sensor networks in an adversarial situation. Resiliency is one of such important parameters. Keeping the connectivity property intact, this paper presents a black-box approach to improve the resiliency of a class of lightweight combinatorial subset schemes, known as CRT-Subset schemes. We have developed unidirectional hash chains for CRT-Subset (HC(CRT-Subset)) by using key doublets through the use of a hash chaining mechanism. The idea extends to a key triplet to manufacture the bidirectional hash chains for CRT-Subset (2HC(CRT-Subset)) scheme. These ideas are explained through four Algorithms. Given the number of nodes required for a system to be implemented for practical purposes, our algorithms are capable of finding suitable parameters to efficiently construct the key rings for future cryptographic communications. They also provide efficient mechanisms to find common keys between two nodes. Furthermore, we have shown that both of our proposed methods are more resilient than the vast majority of existing schemes. Schematic analyses and comparisons exhibit the improvement achieved and thus ensure the practicality in (distributed) deployment for large (low-cost) networks. We observe that in a multi-key scenario, like our proposed resiliency improved variants of CRT-Subset schemes, the standard resiliency measure, $f a i l (s)$ , does not cover the full picture. So, we additionally introduce a new security parameter $T_{s}$ to measure the robustness of a network. It is mathematically a challenging problem to calculate the exact values of $T_{s}$ as well as $f a i l (s)$ . We compute a bound of $T_{s}$ for CRT-Subset and find the exact mathematical expression of $f a i l (s)$ and $T_{s}$ for the CRT-KPS scheme. In addition, we come up with a compact expression of $T_{1}$ for the CRT-Subset Scheme.
Two-dimensional diagonal layer hash chain based key pre-distribution scheme
2021, Journal of Information Security and Applications
Citation Excerpt :
Obviously, the results of this paper can be applied to other general schemes. To further enhance resiliency and meantime retain the same connectivity, some hash chain based KPD (HC-KPD) schemes [12, 19] were proposed. However, the HC- KPD schemes have to perform more hash operations to establish a secure link between two neighbor nodes.
Recently, Ehdaie et al. proposed a two-dimensional hash chain based key pre-distribution (2DHC-KPD) scheme that can enhance resiliency against node-capture attack when compared with the conventional hash chain based key pre-distribution (HC-KPD) scheme. However, these HC-KPD-like schemes cannot resist the advanced node-capture attack (ANA) that attackers have the knowledge of the identifiers of sensor nodes. In this paper, we adopt the diagonal layer from the two-dimensional key map in 2DHC-KPD scheme to design the diagonal layer hash chain based key pre-distribution (DLHC-KPD) scheme. Compared with all HC-KPD-like schemes, our DLHC-KPD scheme has the best resiliency against node-capture attack, and is also the only scheme that can resist against the ANA. The trade-off is more hash operations.
AHKM: An improved class of hash based key management mechanism with combined solution for single hop and multi hop nodes in IoT
2021, Egyptian Informatics Journal
The extensive growth of the Internet of Things (IoT) devices leads to the evolution of the broad range of smart applications in numerous fields such as smart home, wearable, education, agriculture, health care, transportation and many more. But security for IoT devices is still a challenging issue as many attacks are possible in the environment. Therefore strong security requirements are an important concern to safeguard the IoT smart devices. The sensor network has to select an efficient encryption algorithm to provide secure communication between sensor nodes. The basic requirement for encrypted communication is key establishment and distribution. The currently available key management process involves large computational overhead, energy consumption, and delay. This makes the network inefficient since sensor nodes have limited bandwidth capacity. The main aim of this paper is to establish a strong key management mechanism to overcome the issues in the current cluster based key management technologies. The work proposed a secure hash key-based key management scheme for the cluster based network environment. The proposed scheme considers the two-level verification process, a one-hop way for the nodes within the cluster and a multi-hop way for the nodes outside the transmission range. The work done is examined through simulation by varying the number of malicious nodes in the environment. The result shows that the rate of packet loss has been reduced when compared with a one-hop way of key management solution. The proposed work also enhances the performance of the network by lowering the energy, computational overheads, and delay.
An attack resistant key predistribution scheme for wireless sensor networks
2021, Journal of King Saud University - Computer and Information Sciences
Most of the key management schemes do not consider the attacking behavior of the adversary making such schemes less practical in real world. By knowing the adversarial behavior, several countermeasures against them can be effectively and efficiently designed by the defender/network designer. In this paper, we investigate the problem of node capture attack and propose a secure hybrid key predistribution scheme (HKP-HD) for wireless sensor networks (WSN). This scheme combines the robustness of the q-composite scheme with threshold resistant polynomial scheme. The proposed scheme aims to make the network more resistant against the node capture attacks. Adversary is assumed to be intelligent that tends to exploit different vulnerabilities present in network to build an attack matrix. It aims to destroy complete network with least number of nodes based on the attack matrix. As a countermeasure, the network designer constructs similar attack matrix based on the vulnerabilities in the network by considering sink as a major influencing factor. This matrix is used to calculate the attack coefficient of every node of the network that determines its probability of attack by the adversary. A hash chain based on maximum value of attack coefficient along with the multiple key pools is used to reduce the probability of the key compromise and communication overhead of the proposed scheme. The simulation results demonstrate that the proposed scheme has reduced probability of key compromise, communication overhead and storage overhead as compared to other schemes.

View all citing articles on Scopus

View full text