Guaranteed frame rate: A better service for TCP/IP in ATM networks

Guaranteed frame rate, recently approved by the ATM Forum, is expected to b ecome an important service category to efficiently support TCP/IP traffic i n ATM networks. We first describe the GFR traffic contract in details. We t hen present different types of switch implementations that have been propos ed to support GFR. We analyze the performance of three of these switch impl ementations by simulations in two different network environments. These sim ulations show that the scheduler-based implementations provide a much bette r performance than the simple switch implementation. However, we also show that coupling an active pocket discord mechanism to a scheduler-based switc h implementation does not produce a performance gain when many TCP connecti ons are multiplexed inside one ATM VC.