1,836 research outputs found
Maximum Production Of Transmission Messages Rate For Service Discovery Protocols
Minimizing the number of dropped User Datagram Protocol (UDP) messages in a network is regarded as a challenge by researchers. This issue represents serious problems for many protocols particularly those that depend on sending messages as part of their strategy, such us service discovery protocols. This paper proposes and evaluates an algorithm to predict the minimum period of time required between two or more consecutive messages and suggests the minimum queue sizes for the routers, to manage the traffic and minimise the number of dropped messages that has been caused by either congestion or queue overflow or both together. The algorithm has been applied to the Universal Plug and Play (UPnP) protocol using ns2 simulator. It was tested when the routers were connected in two configurations; as a centralized and de centralized. The message length and bandwidth of the links among the routers were taken in the consideration. The result shows Better improvement in number of dropped messages `among the routers
Location-aware service discovery on IPv6 GeoNetworking for VANET
Conference is technically co-sponsored by IEEE Communications Society and co-organized by the Technical Sub-Committee on Vehicular Networks and Telematics (VNAT)International audienceService discovery is an essential component for applications in vehicular communication systems. While there have been numerous service discovery protocols dedicated to a local network, mobile ad-hoc networks and the Internet, in vehicular communication systems, applications pose additional requirements; They need to discover services according to geo- graphical position. In this paper, we propose a location-aware service discovery mechanism for Vehicular Ad-hoc NETwork (VANET). The proposed mechanism exploits IPv6 multicast on top of IPv6 GeoNetworking specified by the GeoNet project. Thanks to the GeoBroadcast mechanism, it efficiently propagates service discovery messages to a subset of nodes inside a relevant geographical area with encapsulating IPv6 multicast packets. We implemented the mechanism using CarGeo6, an open source implementation of IPv6 GeoNetworking. Our real field evaluation shows the system can discover services with low latency and low bandwidth usage in VANETs
Security and Privacy Issues in Wireless Mesh Networks: A Survey
This book chapter identifies various security threats in wireless mesh
network (WMN). Keeping in mind the critical requirement of security and user
privacy in WMNs, this chapter provides a comprehensive overview of various
possible attacks on different layers of the communication protocol stack for
WMNs and their corresponding defense mechanisms. First, it identifies the
security vulnerabilities in the physical, link, network, transport, application
layers. Furthermore, various possible attacks on the key management protocols,
user authentication and access control protocols, and user privacy preservation
protocols are presented. After enumerating various possible attacks, the
chapter provides a detailed discussion on various existing security mechanisms
and protocols to defend against and wherever possible prevent the possible
attacks. Comparative analyses are also presented on the security schemes with
regards to the cryptographic schemes used, key management strategies deployed,
use of any trusted third party, computation and communication overhead involved
etc. The chapter then presents a brief discussion on various trust management
approaches for WMNs since trust and reputation-based schemes are increasingly
becoming popular for enforcing security in wireless networks. A number of open
problems in security and privacy issues for WMNs are subsequently discussed
before the chapter is finally concluded.Comment: 62 pages, 12 figures, 6 tables. This chapter is an extension of the
author's previous submission in arXiv submission: arXiv:1102.1226. There are
some text overlaps with the previous submissio
Internet-wide geo-networking problem statement
This document describes the need of specifying Internet-wide location-aware forwarding protocol solutions that provide packet routing using geographical positions for packet transport
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