Gopal Pandurangan

Building low-diameter P2P networks

In a peer-to-peer (P2P) network, nodes connect into an existing network and participate in providing and availing of services. There is no dichotomy between a central server and distributed clients. Current P2P networks (e.g., Gnutella) are constructed by participants following their own uncoordinated (and often whimsical) protocols; they consequently suffer from frequent network overload and fragmentation into disconnected pieces separated by choke-points with inadequate bandwidth. The authors propose a simple scheme for participants to build P2P networks in a distributed fashion, and prove that it results in connected networks of constant degree and logarithmic diameter. It does so with no global knowledge of all the nodes in the network. In the most common P2P application to date (search), these properties are important.

Building low-diameter peer-to-peer networks

Peer-to-peer (P2P) computing has emerged as a significant paradigm for providing distributed services, in particular search and data sharing. Current P2P networks (e.g., Gnutella) are constructed by participants following their own uncoordinated (and often whimsical) protocols; they consequently suffer from frequent network overload and partitioning into disconnected pieces separated by choke points with inadequate bandwidth. We propose a protocol for participants to build P2P networks in a distributed fashion, and prove that it results in connected networks of constant degree and logarithmic diameter. These properties are crucial for efficient search and data exchange. An important feature of our protocol is that it operates without global knowledge of all the nodes in the network.

Distributed Verification and Hardness of Distributed Approximation

We study the verification problem in distributed networks, stated as follows. Let

Robust computation of aggregates in wireless sensor networks: distributed randomized algorithms and analysis

H

Distributed Algorithms for Constructing Approximate Minimum Spanning Trees in Wireless Sensor Networks

be a subgraph of a network

Robust Computation of Aggregates in Wireless Sensor Networks: Distributed Randomized Algorithms and Analysis

G

Fast distributed PageRank computation

where each vertex of

Efficient distributed approximation algorithms via probabilistic tree embeddings

G

Fast byzantine agreement in dynamic networks

knows which edges incident on it are in

A random graph approach to NMR sequential assignment

H