DiCoR: Distributed Cooperative Repair of Multimedia Broadcast Losses

Multimedia Broadcast/Multicast Service (MBMS) allows a common broadcast channel to be shared by users interested in identical content. The authors explore the problem of enhancing MBMS resilience by repairing packets lost during broadcast. Since MBMS broadcast consumes expensive 3G resources, the authors leverage the ubiquity of multi-homed mobile devices i.e., devices having both cellular and IEEE 802.11 wireless interfaces. The authors thus accomplish out-of-band repair of MBMS packet losses through an ad-hoc, peer-to-peer 802.11-based network. A fundamental challenge in scheduling repair transmissions is handling interference between distributed nodes. They present DiCoR, a fully distributed protocol for CPR.