New Broadcast Paradigm in collaborative environmentsANY SOURCE P-BROADCAST (ASPB) - Many broadcast sources - Packet reception from the source at the receivers is opportunistic Examples of ASPB Schemes: - Gossip - Mobility-assisted information diffusion - Rendezvous-point store and queryProblem of Applying TESLA on ASPB Traffic1) Hash chain commitment storage for profuse senders2) Authentication delay deteriorates - Deterministic packet losses - ASPB TrafficIntegrity Protection of Broadcast for mission critical applications in mobile ad hoc wireless networksPrior Arts: TESLA and its variations + Low communication and computation overhead + Scalability to a large number of receivers + Tolerance to packet loss.AnyPCast: A Scalable Authentication Protocolfor Any-Source P-BroadcastIllinois Center forWireless SystemsIntroductionMotivation - AnyPCast

Hash Chain Pre-distribution & Sharing3) Infrequent Public Key Authentication1) Hash Chain Group2) Broadcast Authentication key recvedSign messageMAC MAC Validate SignatureMAC MAC key recvedAcceptCAUSE: One hash chain is exclusively owned by one identity (device).Problem

ExperimentAssumption:Locality-P Traffic Model: Small world model A node v chooses N*p random nodes to send one packet per round. A node A is chosen with probability proportional to . d(A, v) is the hop distance from node v to node ASystem ConfigurationAuthentication DelayAnyPCast: Broadcast Authentication Protocol Scalable to a large number of senders Reduces packet authentication delay in path failure and prob. Brdcsting: Mobile, Dynamic Topology, Random Traffic Pattern Supports dynamic node additionConclusionFuture Work+ Online hash chain updating,+ System reconfiguration+ Location-aware hash chain group management

Ying HuangWenbo HeKlara Nahrstedthuang23@uiuc.eduwenbohe@uiuc.eduklara@cs.uiuc.edu

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