Shafique Ahmad Chaudhry

LNMP- Management architecture for IPv6 based low-power wireless Personal Area Networks (6LoWPAN)

Wireless sensor networks (WSNs) are becoming increasingly important because of their reduced cost and a range of real world military applications. IP connectivity to WSNs has enabled ubiquity of devices. 6LoWPAN networks are the realization of these IP based Ubiquitous Sensor Networks (IP-USNs). Management of such low power and constrained networks is a crucial problem. In this paper we propose LoWPAN Network Management Protocol (LNMP) which is the management architecture for 6LoWPAN based WSNs. We present operational and informational architectures for 6LoWPAN. Moreover, we also propose the design of the management information base for the management of such networks.

HYWINMARC: an autonomic management architecture for hybrid wireless networks

The envisioned realization of ubiquity has resulted into the emergence of new kinds of the hybrid networks. The modern hybrid networks, e.g. combination of wireless mesh and Mobile Ad-hoc Networks (MANETs), help realize ubiquity through spontaneous networking. The network management for these hybrid networks is different from conventional and infrastructure based network management. Heterogeneity, mobility, dynamic topologies, physical security, and survivability make the challenge hard. A new class of management called self-management can effectively be used to cater for the autonomous behavior of hybrid networks. We present HYbrid WIreless Network Management ARChitecture (HYWINMARC), a three-tier framework, covering all the management levels, for autonomic network management for hybrid networks. We integrate policy-based network management with mobile-agent technology and design a prototype for a context-aware and self-managing architecture. The context information is collected, from all levels in network hierarchy through monitoring agents, and is used to apply needed self-management operations that include self-optimization, self-healing, self-configuration, and self-growing.

A proxy-enabled service discovery architecture to find proximity-based services in 6LoWPAN

Recent advances in wireless communication and sensor and actuator technologies have played an essential role to realize the envisioned ubiquitous world. Wireless sensor networks (WSNs) have emerged as a great catalyst for morphing personal area networks (PANs) into low power personal area networks (LoWPANs) which itself is a channel to achieve higher degrees of ubiquity and pervasiveness. These LoWPANs need to be connected with other wireless and wired networks in order to maximize the utilization of information and other resources which are mainly associated with the IP networks. Interworking of LoWPANs with IP networks brings in many challenges for service discovery and network selection. A great problem in this scenario is to find and use services in the closest proximity of the user. In this paper we propose novel service discovery architecture and algorithms that help proximity based service discovery and network selection within an IP network and LoWPAN interworked environment. The results show that our architecture helps finding and using the closest services from inside as well as outside the LoWPAN. It also reduces the traffic overhead for service discovery considerably as compared to other protocols.

Proxy-Based service discovery and network selection in 6LoWPAN

Low Power Wireless Personal Area Networks (LoWPANs) have emerged as a catalyst technology for the realization of envisioned ubiquitous paragon. Considerable efforts are being carried on to integrate these LoWPANs with IP-based networks in order to make use of pervasive nature and existing infrastructure associated with IP-based technology. Provisioning of service discovery and network selection in such environments puts heavy communication and processing overhead. The access to closest services localizes the communication and increases the total network capacity. We introduce directory proxy agents to be deployed within LoWPANs in order to localize the service discovery communication. We also propose algorithms to make sure that service users are always connected to the closest proxy agent. The results show that our algorithms help finding the closest services and reduce the traffic overhead for service discovery considerably in LoWPANs.

Route error reporting schemes for on-demand routing in 6LoWPAN

Due to their rapid growth and new paradigm applications, wireless sensor networks are morphing into low power personal area networks (LoWPANs), which are envisioned to grow radically. To achieve higher degrees of pervasiveness these LoWPANs must be connected to the wired networks where most of information resources reside. Integration of IPv6 with LoWPANs poses many challenges; the hardest of them, probably, is the difference in packet size. Solution to this problem demands new packet format definition, packet header compression, and a fragmentation and reassembly layer. Header compression techniques suggest different schemes including removal of source nodes address from the packet header. In this paper we analyze the effects of eliminating the source address from the packet header and then propose solutions to propagate the route error message (RERR) to the source even without having the source address. We make use of MAC layer address for sending the RERR to the previous hop node, back tracking the route hop by hop, eventually to the source. The simulation results show that the proposed solutions deliver RERRs to the source even without the source address.

NETSAQ: network state adaptive qos provisioning for MANETs

The provision of ubiquitous services in Mobile Ad-hoc Networks (MANETs) is a great challenge, considering the bandwidth, mobility, and computational-resources constraints exhibited by these networks. Incorporation of modern delay-sensitive applications has made the task even harder. The traditional Quality of Service (QoS) provisioning techniques are not applicable on MANETs because such networks are highly dynamic in nature. The available QoS provisioning algorithms are either not efficient or are embedded into routing protocols adding a high computation and communication load. In this paper, we propose a Network State Adaptive QoS provision algorithm (NETSAQ) that works with many underlying routing protocol. It ensures the QoS provisioning according to the high level policy. NETSAQ is simple to implement yet minimizes the degradation of the best effort traffic at a considerable level. Our simulation results show that NETSAQ adapts well in MANET environments where multiple services are contending for limited resources.

Mitigating broadcast storms in stateless address auto-configuring MANETs

MANETs that form user groups on the fly may never undergo predeployment address configuration. The stateless autoconfiguration capability is therefore essential to the spontaneity of such community networks. Of several address autoconfiguration schemes, no singular scheme meets the diversity and heterogeneity of MANET environments. In this paper, we present a duplicate address detection mechanism for mobile ad hoc networks, which is distributed and poses no additional cost on the communication. Analytical results are suggestive of mitigation in broadcast storms that swarm the network every time a node assigns itself an IP address.

Autonomic network management for wireless mesh and MANETs

The realization of the envisioned ubiquitous computing paragon has resulted into new breeds of hybrid networks, e.g., u-Zone [1]. In u-Zones, a high-speed wireless mesh is used as the backbone—allowing MANETs nodes to be connected as a stub network. Hybrid in their nature, these networks belong to the generation of networks that deal with high levels of heterogeneity, mobility, and variability.