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iP2P: A Peer to Peer System for Mobile Devices

Advisor : Whai-En Chen Speaker : Yen-Neng Pan

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

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Introduction

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.

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Introduction (Cont.)

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.

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iP2P Architecture

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.

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Public to Public

STUNT#2 Approach

STUNT#2 Approach (Cont.)

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STUNT Approach (private to private)

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The Mapping Entry Example

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Issue of STUNT Approac h

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.)

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UPnP Approach (private to private)

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Conclusion

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:21.724 sec SMS Delivery time: 2.637 sec WiFi Network Attach time :9.428 sec

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Conclusion(Cont.)

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