On the Capacity Scalability of Line Networks with Buffer Size Constraints

The communication capacity of a network of line topology is studied, where only two adjacent nodes are connected by communication channels, and the intermediate network nodes have a buffer size constraint. Let L be the number of hops from the source node to the destination node. For general channels, we provide schemes to achieve Ω(1/ ln L) rates using a buffer of size B 1 + B 2 bits, where B 1 does not change with L and B 2 = O(ln ln L). In particular, B 1 bits of the buffer are used to store the data generated from the communication messages, and the other B 2 bits of the buffer are used to store the status of counters with the maximum value O(ln L).