Presence Overview


What is Presence?

SIMPLE based presence technology is evolving and is used for managing userís presence information. Presence information includes userís reachability and willingness to communication information. There are lots of sources of presence like IM client, calendar applications, Cell-Phones. Presence information from each of these sources is aggregated and distributed to watchers (buddies). The users (presentities) specify access control using privacy filters (presence authorization rules) based on which each watcher may get different presence information. The watchers can also specify their preferences about when they want to receive presence information and what part of presence information they are interested in using the watcher-filtering rules. Presence server manages and aggregates presence information of presentities, maintains subscription information for each presentity to distribute presence data when requested or when it is changed, applies privacy filters and watcher filters.

  • Read the following tutorial on presence [ Presence Tutorial ] to learn more about presence technology.

    Presence Server Performance and Benchmarking Standard (SIMPLEstone)


    Presence systems need to be appropriately dimensioned to meet the growing number of users, varying number of devices as presence sources, the rate at which they update presence information to the network and the rate at which network distributes the userís presence information to the watchers. SIMPLEStone proposes a simple set of metrics for benchmarking the performance of presence system based on SIMPLE. SIMPLEStone benchmarks the presence server by generating requests based on a work load specification. It proposes to measure server capacity in terms of request handling capacity as an aggregate of all types of requests as well as individual request types.

  • Read the following paper on Presence server performance [ SIMPLEStone Paper ] for more details.
  • Read the following short paper on Presence scalability architecture [ Presence Scalability Architecture ] for more details.

    Presence Security Issues


    Presence information privacy and anonymity is important to the users. The following paper describes Presence security issues. It also touches the problem of trusted service provider and proposes a solution to achieve anonymity from the presence service provider or the presence server.

  • Read the following survey paper on Presence security issues [ Presence Security Survey ] for more details.

    Presence Server Design and Reference Implementation


    Will be updated soon.

    Presence based services (projects)


    Presence architecture based fleet management solution: Presence event notification architecture can be leveraged in different ways. The fleet management application has vechicle's location information as presence data. This data is obtained using GPS and sent to the presece server. The presence server aggregates vehicle's location information with the user's presence information which may be obtained from his cell-phone or any other device.

  • Visit the project page at following location [ Presence based Vehicle Tracking ] for more details.

    Presence based call redirection and rendezevous service: In this application, the call was automatically redirected to the user's current device based on his presence information, e.g, when user moves from his desk to campus, the calls to his desk phone are automatically forwarded to his cell-phone.

  • Visit the project page at following location [ Presence based call control ] for more details.

    For More information


  • Visit [IETF SIMPLE Working group ] for more details.
    vs2140 @cs.columbia.edu