Manzoor Hashmani

Design and analysis of the security assessment framework for achieving discrete security values in wireless sensor networks

The paper presents a ready-to-use security assessment framework for wireless sensor networks (WSNs). The parameters in the proposed security assessment framework perform independent security assessment of WSNs and of their applications. Our proposed framework uses actual responses of the entities (such as nodes, communication link and network response) to assign numerical values for security assessment of WSNs. The method for calculating the optimal values for each security parameter of the framework is also discussed. Our proposed framework is designed to avoid unwanted impacts of the complexities of security algorithms, communication protocols and strong cryptography. Usually, the complexity of algorithms disguises the actual assessment of the WSN, but the independence of the proposed framework from these security-disguising objects makes this framework better than other assessment frameworks in terms of scalability.

WiMAX Network Optimization - Analyzing Effects of Adaptive Modulation and Coding Schemes Used in Conjunction with ARQ and HARQ

The flexibility of WiMAX framework offers new dimensions for cross-layer optimization and can be exploited to optimize the application performance. This article focuses on identifiers that have direct impact on Quality of Service (QoS)and effect of such identifiers is evaluated through computer simulation using OPNET Modeler 14.5 Wireless Suite. In this paper we have used advanced WiMAX features such as Adaptive Modulation and Coding (AMC), Automatic Repeat Request(ARQ) and Hybrid-ARQ to tune the WiMAX network MAC Layer such that its adaptation improves both capacity and delay (thus optimize the performance). ARQ is treated as higher layer to HARQ. HARQ gives up after maximum retransmissions. HARQ performs fast retransmissions and ARQ takes over in cases HARQ fails after multiple retransmissions. This gives an added layer of protection to data. HARQ is proved to be most suitable (when used with aggressive modulation and coding) for WiMAX due to its hybrid nature as it takes into account both the MAC and link layer. Using ARQ in conjunction with HARQ gives slight improvement in BLER (Block Error Rate) but at the expense of high UL frame utilization.

A Pretty Safe Strategy for Analyzing Discrete Security Assessment Framework in Wireless Sensor Networks

The current research and development in the wireless sensor networks (WSNs) make them an ideal infrastructure for variety of applications. Various commercial projects are in need of an increased and on-demand security of WSNs due to varying security requirements. To fulfill these requirements, the develop-ment of application-specific security frameworks of WSNs has been an open area for research. In order to determine the security strength of various security frameworks, we formulate a cooperative strategy to perform assessment of these frameworks through (D-SAFE) Discrete Security Assessment FramEwork.

A New Algorithm to Resource Reservation for Prioritized Traffic in MANETs

In this paper we have given an algorithm for ad hoc networks with respect to their use in commercial production, emergencies, mission critical and broadcasting scenarios where real time transmission require guaranteed QoS. To service these environments our algorithm is designed in such a way so that it provide full package for handling QoS starting from the traffic categories, their route selection and most important resource reservation on different paths for different categories of traffics on their priority. Our designed algorithm supports to a premeditated policies to resource reservation for prioritized traffic in multi-hop ad hoc networks

Optimizing WiMAX: A Dynamic Strategy for Reallocation of Underutilized Downlink Sub-Frame to Uplink in TDD Mode

WiMAX networks experience sporadic congestion on uplink when applications running at subscriber stations need more bandwidth to transmit than allocated. With the fast proliferation of mobile Internet, the wireless community has been looking for a framework that can address the issue of impediment on uplink. Due to asymmetric behavior of Internet applications downlink sub-frame is expected to have longer duration as compared to uplink. According to IEEE 806.16 standard for WiMAX the segmentation of TDD frame between uplink and downlink can be dynamically redefined even at runtime. Research contributions so far lack in addressing an optimal strategy for readjustment of uplink and downlink sub-frame boundaries; based on traffic statistics. In this paper, we introduce a mechanism that allows uplink sub-frame to grow, borrowing resources from the downlink sub-frame, if the uplink utilization is high and the downlink is being underutilized. We present here, a framework to dynamically demarcate the TDD frame-duration between uplink and downlink. Proposed algorithm takes into account the present utilization of downlink and reallocates a certain quantum of free resources to uplink. This occurs when uplink observes shortage of bandwidth to transmit. We simulate some test scenarios using OPNET Modeler with and without dynamic reallocation capability. The results of our simulation confirm the effectiveness of proposed algorithm which observes a remarkable decrease in end-to-end packet delay. Also, we observe an improvement in throughput at uplink such that, the performance of downlink remains unaffected.

A Framework to Achieve Reverse Channel Multicast in IEEE 802.16 Based Wireless Broadband Networks for Interoperability with IP Networks

The purpose of this paper is to present a framework design to achieve reverse channel multicast support in IEEE-802.16 networks. The unavailability of reverse channel multicast in IEEE 802.16 networks is one of the issues to be resolved in order to achieve its interoperability with IP networks. The interoperability of IEEE 802.16 networks and IP networks is not yet addressed. Forward channel multicast support is inherent in the IEEE-802.16 standard. Achieving reverse channel multicast support, we can enable IP services requiring native multicast support over IEEE-802.16 networks for seamless interoperation. IP network rudiments are mature enough and not likely to be redefined for any new network design; rather the reverse of this is more likely to be worked on. A framework design to achieve reverse channel multicast support is presented introducing a concentrator layer (Multi Node Access Layer) before Base Station (BS) and MARS (Multicast Address Resolution Server) to handle multicast requests.