P. Venkitasubramaniam and L. Tong
"Anonymous Networking for Minimum Latency in Multihop Networks"
Accepted to IEEE Symposium on Security and Privacy,
2008.
The problem of security against timing based traffic analysis in multihop networks is considered in this work. An analytical
measure of anonymity of routes in eavesdropped networks is proposed using the
information theoretic concept of equivocation. For any individual relay,
scheduling strategies are proposed that minimize average packet delay while
ensuring that transmission schedules do not reveal the input-output pairs at
the relay. The scheduling strategies are based on Chaum
mixing, but with a fixed rate of dummy transmissions to minimize latency. Using
the scheduling strategies, the tradeoff between overall network latency and
anonymity in the network is characterized by drawing a connection to
information theoretic rate distortion. Further, a decentralized approach is
proposed and the corresponding performance is analyzed.