Polynomial end-to-end communication

A dynamic communication network is one in which links may repeatedly fail and recover. In such a network, although it is impossible to establish a path of unfailed links, reliable communication is possible if there is no cut of permanently failed links between a sender and receiver. The authors consider for such a network the basic task of end-to-end communication, that is, delivery in finite time of data items generated online at the sender, to the receiver, in order and without duplication or omission. The best known previous solutions to this problem had exponential complexity. Moreover, it has been conjectured that a polynomial solution is impossible. The authors disprove this conjecture, presenting the first polynomial end-to-end protocol. The protocol uses methods adopted from shared-memory algorithms and introduces novel techniques for fast load balancing in communication networks.