Title
Brief Announcement: A Hierarchy of Congested Clique Models, from Broadcast to Unicast
Abstract
The CONGEST model is a synchronous, message-passing model of distributed computation in which each node can send (possibly different) messages of O(log n) bits along each of its incident communication links in each round, where n is the number of computing nodes in the system. In the particular case where the communication network is a complete graph, we have the unicast congested clique model. On the other end is the broadcast version of the congested clique model, in which each node can only broadcast a single message over all its links in each round. In this paper we explore the space, in terms of round complexity, that lies between these two congested clique models. Hence, we parametrize the congested clique model with the range r, the maximum number of different messages a node can send over its incident links in one round. Additionally, we study the effect of the bandwidth b, the maximum size in bits of these messages. We show that the space between the unicast and broadcast congested clique models is very rich and interesting. For instance, we show that a problem (especially designed for this work) takes Ω(n/ log n) rounds in the broadcast model (r = 1), while it can be solved in two rounds if two messages can be sent (r = 2). Other gaps are found in other parts of the spectrum of values of r. We do this by providing techniques to simulate protocols with different parameters. Therefore, we conclude that, with respect to their power to solve certain problems, there is a strict hierarchy of congested clique models.
Year
DOI
Venue
2015
10.1145/2767386.2767447
ACM Symposium on Principles of Distributed Computing
Keywords
Field
DocType
CONGEST model, congested clique model, message passing, distributed computation
Binary logarithm,Broadcasting,Complete graph,Telecommunications network,Clique,Computer science,Theoretical computer science,Bandwidth (signal processing),Unicast,Message passing,Distributed computing
Conference
Citations 
PageRank 
References 
6
0.46
9
Authors
4
Name
Order
Citations
PageRank
Florent Becker1697.39
Antonio Fernández Anta239341.88
Ivan Rapaport319921.93
Eric Rémila432945.22