Last updated
Developer(s) Thomas Bocek
Stable release
Written in Java
Type peer-to-peer, key-value store
License Apache License 2

TomP2P is a distributed hash table which provides a decentralized key-value infrastructure for distributed applications. Each peer has a table that can be configured either to be disk-based or memory-based to store its values.


Overview and key concept

TomP2P stores key-value pairs in a distributed hash table. To find the peers and store the data in the distributed hash table, TomP2P uses an iterative routing approach. The underlying protocol for all the communication with other peers uses state-less request-reply messaging. Since TomP2P uses non-blocking communication, a future object is required to keep track of future results. This key concept is used for all the communication (iterative routing and DHT operations, such as storing a value on multiple peers) in TomP2P and it is also exposed in the API. Thus, an operation such as get(...) or put(...) will return immediately and the user of the API can either block the operation to wait for the completion or add a listener that gets notified when the operation completes.


See also

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  1. Bocek, T.; PeerCollaboration: [ A Peer-to-Peer Collaboration Application for Large-scale Systems]. ISBN   978-3-8322-9002-3, Shaker Verlag, Aachen, Germany, March 2010. Chapter 7.2.1
  2. Security in TomP2P
  3. Hecht, F.V.; Bocek, T.; Stiller, B.; B-Tracker: Improving load balancing and efficiency in distributed P2P trackers, Peer-to-Peer Computing (P2P), 2011 IEEE International Conference on , vol., no., pp. 310–313, Aug. 31 2011-Sept. 2 2011,
  4. Changelog for TomP2P 4.0.0