In this paper we study some link control protocols for use in point-to-multipoint communication over broadcast links. We concentrate on automatic repeat request protocols of the go-back-N type and define, analyze, and compare three such protocols. A major contribution of this paper is a relatively simple protocol which is easy to implement and performs very well under a wide range of conditions. Our analytical models show that this protocol performs considerably better than the other go-back-N protocols, particularly in environments with a large number of receivers. Copyright © 1984 by The Institute of Electrical and Electronics Engineers, Inc.