Communication complexity of document exchange

We address the problem of minimizing the communication involved in the exchange of similar documents. We consider two users, A and B, who hold documents x and y respectively. Neither of the users has any information about the other's document. They exchange messages so that B computes x; it may be required that A compute y as well. Our goal is to design communication protocols with the main objective of minimizing the total number of bits they exchange; other objectives are minimizing the number of rounds and the complexity of internal computations. An important notion which determines the efficiency of the protocols is how one measures the distance between x and y. We consider several metrics for measuring this distance, namely the Hamming metric, the Levenshtein metric (edit distance), and a new LZ metric, which is introduced in this paper. We show how to estimate the distance between x and y using a single message of logarithmic size. For each metric, we present the first comm...

• Type: Conference
• Year: 2000
• Where: SODA
• Authors: Graham Cormode, Mike Paterson, Süleyman Cenk Sahinalp, Uzi Vishkin
• Keywords: Algorithms, Edit Distance, Hamming Metric, Similar Documents, SODA 2000