Service Location Protocols for mobile wireless ad hoc networks

Abstract

As service-oriented networks are essential in our lives, service location, access and provisioning over wired or wireless networks govern users' satisfaction. While they are well understood over cellular networks, it is not clear for ad hoc networks. We therefore present several approaches on service location in such networks: distributed broadcast query, query via service coordinators, and a hybrid combination. Particularly, we evaluated these approaches in terms of service availability and control overhead over variable network sizes and mobility scenarios. Simulation results showed that the distributed query approach suffered from high control overhead despite its robustness and tolerance towards mobility. The service coordinator (SC) based approach, however, resulted in a more scalable architecture that tends to separate the network into different service areas. This has important implications on future "mobile marketplace" and services to mobile users. Finally, the hybrid approach provided greater flexibility and robustness to the SC-based approach with its scoped broadcast to limit the overhead.

تعديل بروتوكول اكتشاف الخدمة الصغيرة (MTinySDP) للتغلب على مشكلات التنقل

“…An ETF (Internet Engineering Task Force) which provides a standard for network applications [3], tools for service discovery in a distributed environment. SLP is a tool for discovering services and advertising on IP networks and intensively uses TCP and UDP protocols.…”

“…SDP_NBR metric represents the count of closest neighbor nodes. Each node selects closest three neighbor nodes to send service advertisements message, as shown in Figure (3). A node sends an advertisement to its neighbor, if the advertisement table of the selected neighbor has already three previous advertisements, then the source chooses the next closest neighbor, depending on the number of hop no more than five in such a case to are configured Hex-Cell.…”

“…A node sends an advertisement to its neighbor, if the advertisement table of the selected neighbor has already three previous advertisements, then the source chooses the next closest neighbor, depending on the number of hop no more than five in such a case to are configured Hex-Cell. This prevents the construction of tri-cell network, as shown in Figure (3). But allows the construction of Hex-Cell Network [1] and can be built using hexagon unit cells, each of the six nodes, as shown in Figure (4).…”

“…First, Centralized approach is optimal in terms of the speed of data access and low traffic, although it creates a single point of failure. SLP with a Directory Agent [3] and Jini [18] are examples that have a central server for information storage. They use the server only for information retrieval, the actual communication between the client and the server being done in a peer-to-peer manner.…”

Below Cross-Layer: An Alternative Approach to Service Discovery for MANETs

“…These protocols may be classified as either service coordinator, distributed query-based or hybrid architectures [17].…”