03218nas|a2200289 a 450000500170000000800410001703500150005810000220007324500990009526000670019430000430026149000280030450001880033250200580052052018260057865000230240465000500242765000400247770000450251770000430256270000470260570000420265270000410269471000670273581000600280285600660286220260817162438.0100309s2009    th uu|m rtt   0|  a1eng d  a.b1207410x1 aGhimire, Jagadish10aAnalysis of supernode based peer-to-peer system for IP telephony over wireless ad hoc networks  aPathum Thani, Thailand :bAsian Institute of Technology,c2009  a89 leaves :bill. +e1 online resource1 aThesis ;vno. ICT-09-03  aA thesis submitted in partial fulfillment of the requirements for thedegree of Master of Engineering inInformation and Communication Technologies, School of Engineering and Technology  aThesis (M.Eng.) - Asian Institute of Technology, 2009  aThis thesis work is in relation to the Supernode(SN)-based Peer-to-Peer (P2P) service control overlay for IP telephony service over wireless ad hoc networks.  The first part of the work considers the problem of analyzing Session Set-up Delay (also known as post-dialling delay) and capacity of SN-based P2P overlay. Owing to the fact that IP telephony services are supposed to operate below a certain average post-dialling delay, analysis of lookup delay becomes important in the scenario of IP telephony. Capacity in terms of lookup processing is another performance parameter that determines the maximum number of users the system can support without a high call-drop rate. In this thesis work, we have followed a mathematical approach to derive closed-form expressions for the mean lookup delay and capacity of ring-topology and chord based service control overlay as a function of the number of SNs. The derivations are verified using equivalent simulations. Lower bounds on the number of underlay hops traveled by a lookup message in a wireless ad hoc network have also been proposed.  The results show that, for a given lookup query load into the system, there exists a number of SNs where the overlay lookup delay is minimum. The results also show that capacity might not always increase arbitrarily with an increase in number of SNs. We find that overlay topological structure can have a very significant impact in the capacity scaling of such networks.  The second part of the work defines a node connectivity index (CI) as a "one»valued" measure of quantifying connectivity of a node in a wireless ad hoc network. We use the proposed CI as a criteria of SN selection. We show by simulations that the SN selection based on proposed CI criteria result in more robust overlays against random link and node failure 0aInternet telephony 0aPeer-to-peer architecture (Computer networks) 0aAd hoc networks (Computer networks)0 aTeerapat Sanguankotchakorn,eChairperson1 aErke, Tapio J.,eExamination Committee1 aRajatheva, R.M.A.P,eExamination Committee1 aCrespi, Noel, eExamination committee1 aMani, Mehdi, eExamination committee2 aAsian Institute of Technology Fellowship, eScholarship donor 2 aAsian Institute of Technology.tThesis ;vno. ICT-09-03  3Full-Textuhttp://203.159.5.9/ait-thesis/detail.php?q=B03143