Packet collisions and their resolution create a performance bottleneck in random access LANs. A hardware solution to this problem is to use collision avoidance switches. These switches allow the implementation of random access protocols without the penalty of collisions among packets. The simplest network based on collision avoidance is the Broadcast Star network, where all the stations are connected to a central switch. A more sophisticated architecture based on collision avoidance is the CAMB (Collision Avoidance Multiple Broadcast) Tree network, where concurrent broadcast is possible. This paper presents a design of a collision avoidance switch for the CAMB Tree using TTL devices. Simulation study exploring the performance of the Broadcast Star network in both synchronous and asynchronous operations is also presented in this paper
