Gated-scheduling algorithms in packet switching networks

In this paper, two novel scheduling algorithms with low implementation complexity are investigated. Most scheduling algorithms proposed so far usually involve a sorting operation with the complexity of O(logN) per packet, where N denotes the number of connections sharing the link. To solve this problem, we propose two new scheduling algorithms with the complexity O(1), implemented with only a single FIFO queue in the output scheduler. The proposed scheduling algorithms make use of the concept of gated scheduling, and thus the schedulers are called gated-scheduling servers (GSS). The key contribution of the GSS algorithms is the successful elimination of output sorter in their designs such that the scheduling mechanism can accommodate a large number of flows. Both delay bounds and fairness index for flows scheduled under these two algorithms are validated with simulations.