Amirhossein Moravejosharieh

Review: A survey of secure protocols in Mobile IPv6

Mobile IPv6, also known as MIPv6, is an IP-layer protocol that offers mobility support. The MIPv6 protocol allows Mobile Nodes (MNs) to remain connected to Correspondent Nodes (CNs), even when moving to foreign networks. Basically, MNs may change their position throughout the IPv6 network while retaining their existing connections by managing address variations in the Internet layer. Numerous advantages are thus attained, but security remains a fundamental concern. According to our research, a number of protocols can form a secure connection environment between MNs and CNs, though each has advantages and disadvantages. This paper presents a state-of-the art survey of security protocols in MIPv6. Moreover, we propose taxonomy, and comparative study that does not exist in the surveys in the literature. Along with the location management feature within these protocols, potential attacks and security threats, together with the security services and requirements are necessary for minimizing such problems, are subsequently presented.

Overview of Mobile IPv6 Security

Mobile IP enables a mobile node to be recognized via a single IP address even though the node may travel from one network to another. Despite reposition between different networks, connectivity at different positions is attained continuously with no user intervention. Mobile IP grants connectivity to nodes everywhere, whether within home networks or away from home. General improvement in MIPv6 may offer enhanced security, however, there are areas still prone to attacks. Security solutions for the mobile IP protocol are still in progress. IP Security (IPsec) in the IPv6 protocol can secure Mobile IPv6 more than IPv4. IPsec presents security services for the application and transportation layer protocols of the TCP/IP stack. However, there are several unsolved concerns and problems with Mobile IPv6 in most cases which justifies development of new methods to provide acceptable level of security. This article focuses on how IPsec works, Mobile IPv6 security, potential threats and security considerations.

A survey of IEEE 802.15.4 effective system parameters for wireless body sensor networks

Summary Wireless body sensor networks are offered to meet the requirements of a diverse set of applications such as health-related and well-being applications. For instance, they are deployed to measure, fetch and collect human body vital signs. Such information could be further used for diagnosis and monitoring of medical conditions. IEEE 802.15.4 is arguably considered as a well-designed standard protocol to address the need for low-rate, low-power and low-cost wireless body sensor networks. Apart from the vast deployment of this technology, there are still some challenges and issues related to the performance of the medium access control (MAC) protocol of this standard that are required to be addressed. This paper comprises two main parts. In the first part, the survey has provided a thorough assessment of IEEE 802.15.4 MAC protocol performance where its functionality is evaluated considering a range of effective system parameters, that is, some of the MAC and application parameters and the impact of mutual interference. The second part of this paper is about conducting a simulation study to determine the influence of varying values of the system parameters on IEEE 802.15.4 performance gains. More specifically, we explore the dependability level of IEEE 802.5.4 performance gains on a candidate set of system parameters. Finally, this paper highlights the tangible needs to conduct more investigations on particular aspect(s) of IEEE 802.15.4 MAC protocol. Copyright

Study of target tracking and handover in Mobile Wireless Sensor Network

Mobile Wireless Sensor Networks (MWSN) are becoming increasingly common these days and are hugely used in different applications like remotely monitoring health of patients, wild life tracking, localization and target tracking. In all these applications, mobile sensor nodes associate and communicate with different fixed coordinators. Reliable data transmission, maintaining an acceptable level of resiliency, providing seamless handover, effective target tracking and low energy consumption are few of the key requirements of effective communication in MWSNs. Out of these, the work done in this paper focuses on target tracking and the tangible need to have a seamless as well as fast handover in MWSNs. A few studies have been conducted to evaluate the performance of the IEEE 802.15.4 Media Access Control (MAC) layer in MWSNs. Moreover, the paper proposes three different target tracking schemes as part of the handover activity of sensor nodes to demonstrate the feasibility of experiencing seamless handover procedure. The schemes are properly validated through simulation studies.

Study of resource utilization in IEEE 802.15.4 Wireless Body Sensor Network, Part II: Greedy Channel Utilization

The channel scarcity phenomenon has recently introduced new challenges in the field of Wireless Body Sensor Networks (WBSNs). Within a WBSN, nodes communication is restricted throughout their defined active period. As the number of WBSNs increases, the overlapping active periods are elevated due to inefficient utilization of the spectrum. This consequently results in higher packet loss ratio and eventually performance degradation of the WBSNs entirely. To overcome the aforementioned issue, in this paper, we have proposed a new scheme called “Greedy Channel Utilization” (GCU) scheme in which coordinators compete for slot reservation and attempt to utilize the channel voraciously by pushing other contestants in to sleep mode. To evaluate the performance of our proposed scheme, we compared it with the bare IEEE 802.15.4 Std. in terms of channel utilization percentage, packet loss ratio, sensors orphan time and energy consumption of sensors and coordinator. Eventually, this study concludes the outperformance of GCU scheme over the blind scheme.

Mutual interference in large populations of co-located IEEE 802.15.4 body sensor networks-A sensitivity analysis

We consider scenarios where a large number of wireless body sensor networks (WBSN) meets at the same location, as can happen for example at sports events, and assess the impact of their mutual interference on their achievable transmission reliability. In particular, we consider several of MAC- and application parameters for a range of static and dynamic schemes for allocating WBSNs to frequencies, and determine their relative impacts on achievable performance. Our results indicate that parameters related to the MAC backoff scheme have by far the largest impact on performance, and that frequency adaptation can provide substantial performance benefits.

Adaptive channel utilisation in IEEE 802.15.4 wireless body sensor networks: Continuous hopping approach

IEEE 802.15.4 is arguably considered as a well designed standard protocol to address the need for low-rate, low-power and low-cost Wireless Body Sensor Networks (WBSNs). Within a WBSN, Nodes communication occurs during their confined active periods. The increase in number of active WBSNs would consequently result in the elevation of the overlapping ratio between the active periods of neighbouring WBSNs. In this paper, we address the interference caused by neighbouring WBSNs and its devastating consequences. Frequency hopping could be considered as a possible approach to alleviate the WBSNs performance degradation due to such interference. Our proposed “Continuous-Choice” scheme is compared with previously introduced “Initial-Choice” and “Blind-Choice” schemes in terms of channel utilisation, success rate, Satisfaction rate and energy consumption (both sensors and coordinator). Eventually, it is concluded that Continuous-Choice outperforms both Initial-Choice and Blind-Choice schemes in terms of above-mentioned performance measures.

Wireless Network Security Using Elliptic Curve Cryptography

As wireless sensor networks continue to grow, so does the need for effective security mechanisms. Sensor networks may interact with sensitive data and/or operate in hostile unattended environments, it needs to be secured. It is an important challenge to find out suitable cryptography for wireless sensor networks due to limitations of energy, computation capability and storage resources. We present a comparison of two public-key algorithms, RSA and Elliptic Curve Cryptography (ECC). We found ECC to have a significant advantage over RSA as it reduces computation time and also the amount of data transmitted and stored.

Performance evaluation of co-located IEEE 802.15.4-based wireless body sensor networks

Wireless body sensor networks (WBSNs) are expected to play a pivotal role in health-related and well-being applications. In this paper, we consider a situation in which a large number of people wearing body sensor networks are gathered in very close vicinity (as can happen in sport events or emergency hospitals). Clearly, BSNs compete with each other to gain access to the same frequency which results in experiencing mutual (internal) interference. Therefore, we investigate the “internal interference” and its destructive impacts on the overall performance gain of WBSNs using IEEE 802.15.4 standard protocol. As the number of WBSNs increases in the channel, it becomes highly likely for active periods of neighbouring WBSNs to overlap with each other. The increase in overlapping active periods would increase the probability of packet collisions leading to performance degradation. In this paper, two types of interference mitigation strategies are proposed, namely passive schemes and active scheme. The terms passive and active refer to the absence and presence of the capability of communication between WBSNs to efficiently utilise the same frequency spectrum. According to the passive schemes, WBSNs are enabled to change their operating frequencies whenever required to mitigate the impacts of internal interference, whereas active scheme offers collaborative utilisation of the channel. The simulation results show that the proposed active scheme represents the highest performance gains compared to the proposed practical passive schemes.

Adaptive channel utilisation in IEEE 802.15.4 Wireless Body Sensor Networks: Adaptive Phase-Shifting Approach

Research communities have recently focused on the issues related with the internal interference in homogeneous IEEE 802.15.4 Wireless Body Sensor Networks (WBSNs). Frequency-hopping strategies seem to be an effective way to reduce the destructive impact of internal interference on WBSN performance. However, this strategy has its limitations. In this paper, a new strategy called “phase-adjustment” is considered in which occupants of the same channel are capable to communicate with each other by re-arranging their phases in such a way that they become equidistantly spread over time. The new proposed scheme is called Adaptive Phase-shifting Approach and utilises both phase-adjustment and frequency-hopping strategies. The performance of the new scheme is compared with previously introduced initial-, continuous- and blind-choice schemes, by considering satisfaction rate, carrying capacity and energy consumption. The results indicate that the Adaptive Phase-shifting scheme outperforms other considered schemes in terms of the above-mentioned performance measures.