Advisor : Whai-En Chen Speaker : Yen-Neng Pan 1 Author by : Chien-Chn Huang-Fu and Yi-Bing Lin, National Chiao Tung University. Herman Chung-Hwa Rao, Far EasTone Telecommunications Co., LTD. IEEE Wireless Communications April 2009

HYBRID P2P Utilized centralized servers to maintain the mapping between the identifications PURE P2P Query for identifying the transport address of participating peer is flooded through the network To implement a P2P system for mobile devices that have the capability to access mobile telecommunication networks, such as the Universal Mobile Telecommunications System, this paper propose a pure P2Psystem called iP2P. 2

Step 1 – peer start the P2P application, which attach to IP network Step 2 – the peer registers to the centralized server by providing its id and address Step 3 – the calling peer queries the centralized server to retrieve the address of the called peer Step 4 – upon receipt the address, the calling peer establihe a P2P connection to called peer without centralized server. 3

Use Mobile Station ISDN number as the peer identification which is globally unique. The iP2P control message are encapsulated in SMS. iP2P module iP2P Control Function is responsible accessing iP2P Control Message through the SMS API and controlling the connection through the iP2P Socket API iP2P Socket API is the standard socket API with minor modifications. 4

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STUNT solution pose problems: Setting an appropriate TTL value of SYN packet might not be trivial. The port prediction server cannot guarantee to provide transport mapping of the public and private transport address for the NAT server.(especially some NAT server randomly assign.) 10

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iP2P reuse UMTS mobility management mechanism and SMS as th control protocol Implemented the system on Windows Mobile 6.0 Professional OS. The measured data from 200 experiments: Connection set-up time: sec SMS Delivery time: sec WiFi Network Attach time :9.428 sec 12

Advantage Efficient query without a requirement to implement its own centralized server. Use SMS push mechanism to establish P2P connection can significantly save power consumption in the mobile device Allow more flexible IP address allocation 13