1. P2P Info Application P2PIA  Handle user input  Store/Answer Questions  Manage received data TCP/IP and 802.11 P2P Network Layer P2PNL  Pass low-level messages  Manage node-list (known/connected)  NID  physical address mapping SearchChat listen to all messages User Interface Search P2PNL Cache (hot data) Index FS External Search Query Node List internal external updates Cache miss Chat Messages P2PIA Network (TCP/IP) IPC Handler NID / IP tables Callback registry Socket Handler Input / Output Queues App Message Processor P2P Network Processor Connections Node state / Profile System Architecture Application Network User Interface MOBAGE – Mobile P2P Networking Home Search QueriesSearch ResultsChat Motivation  A Peer-to-Peer (P2P) system for mobile devices to allow for sharing of information within a community.  Users may  Passively search or  Actively “chat” to share information Features  Allow free roaming mobile device users to benefit from each other’s information and ideas  Proactively: Chat and directed search  Passively: Capturing others’ searched information  Built with mobile devices in mind  small memory footprint  user interface (UI) considers screen size/input type  Tolerates erratic connections typical of current mobile environments  As powerful as the number of users “online”; desirable scaling behavior Why P2P?  Peer-to-peer (P2P): A method of networking that assumes all hosts are equal; each host both provides and requests services from other hosts.  Advantages:  Scalability  Fault-tolerance  Works without infrastructure  Benefits of deploying as P2P  Technological:  Requires no infrastructure; all that is required is for users to be present.  System “capability” degrades gracefully with users leaving.  Sociological:  People are not always willing to ask strangers for information, even when in a common environment (school, work, etc.)  People not always willing to actively monitor forums, search online, write email, etc. Application  Search  Local and remote light weight search  Simultaneous multi-node remote search (p2p)  Possibility for persistent queries  Chat  Global chat rooms (in the “visible” p2p network)  Dynamic notification of available chat rooms  Persistent chats – allows remote search of chat info Network Layer  Network layout is “unstructured mesh”  Any node may connect to any node  Fixed upper limit of simultaneous connections  Basic assertions of the protocol  Each node has a unique NID  Minimal network state should be maintained due to limited resources  All NID  physical address mapping is handled within the P2PNL Future Work  Deployment on mobile systems  PDAs  Mobile Phones  Low Cost Hardware (e.g. GameBoy)  Network Scalability  P2PNL is a rapid prototype. No optimizations have been implemented, so network scales > 100 nodes may cause slowdown  Search can be especially affected; Broadcasting tends to have exponential impact w.r.t. network size  Presentation of data in UI  Different types of data or manners of searching will have different popularities; adoption of UI might be necessary Advisors: Prof. Asim Smailagic, Prof. Dan Siewiorek {asim,dps@andrew.cmu.edu} Students: Joerg Claussen, Gesly George, Matt Hornyak, David Hsu, Harvey Vrsalovic {claussen,ggeorge,matth,dfhsu,harveyv@andrew.cmu.edu}