Progress Report on the LTS / UMIACS Contract RFP : MDA 904 - 02 - R - 0151 – SOW : R 4 - 02 - 0001 . 1 January 31 , 2004

We first present a protocol for anonymous communication over the Internet. Ourprotocol, called P5 (Peer-to-Peer Personal Privacy Protocol) provides sender-, receiver-,and sender-receiver anonymity. P5 is designed to be implemented over the currentInternet protocols, and does not require any special infrastructure support. We present anoutline of the P5 protocol, and a set of performance results based on detailed simulations. We next present a low-overhead media streaming system, called SRMS (ScalableResilient Media Streaming) that scales to very large groups. SRMS leverages aprobabilistic loss recovery technique to provide high data delivery guarantees even underlarge network losses and overlay node failures. We describe the randomized protcols thatare used to provide resilience in SRMS, and present simulation and implementationresults showing its efficacy in practice. November 5, 2003 Randomized Algorithms for Network Security and Peer-to-PeerSystemsSpeaker: Micah AdlerUniversity of Massachusetts at Amherst AbstractThis presentation will consist of two independent shorter talks, with a question andanswer period in between. The first talk will consider probabilistic packet marking(PPM) for IP Traceback. PPM is a technique for tracing a sequence of network packetsback to an anonymous source. An important consideration for such schemes is $b$, thenumber of packet header bits that need to be allocated to the marking protocol. In thistalk, we introduce a new PPM scheme applicable when a sequence of packets is sentalong the same path. This new technique allows the packets to be traced back to theirsource using only a single bit in the packet header. With this scheme, the number ofpackets required to reconstruct the path is $O(2^{2n})$, but we also show that it is notThis presentation will consist of two independent shorter talks, with a question andanswer period in between. The first talk will consider probabilistic packet marking(PPM) for IP Traceback. PPM is a technique for tracing a sequence of network packetsback to an anonymous source. An important consideration for such schemes is $b$, thenumber of packet header bits that need to be allocated to the marking protocol. In thistalk, we introduce a new PPM scheme applicable when a sequence of packets is sentalong the same path. This new technique allows the packets to be traced back to theirsource using only a single bit in the packet header. With this scheme, the number ofpackets required to reconstruct the path is $O(2^{2n})$, but we also show that it is not