A Design of Adaptive Double Leaky Bucket in Traffic Shaping over VDSL Network

Traffic shaping in high speed networks, including VDSL networks, occurs when congestion builds up in the outgoing VDSL network. Shaping mechanisms want smooth traffic. We used a leaky bucket too achieve traffic shaping. But leaky buckets still have a lot of non-conforming frames. However, as one way to solving this problem, we purpose a double-leaky bucket as the traffic shaping mechanism that has proven to be efficient in coping with conflicting requirements, that is, low non-conforming frames. We evaluate and compare the performance of a double-leaky bucket in traffic shaping mechanisms (DLB) and leaky buckets (LB). The performance of the double-leaky bucket was investigated through fluctuations in telecommunication traffic streams (burst/silent type). Simulation results showed that on VDSL frames, a double-leaky bucket helps improve the performance in a traffic-shaping system much better than conventional, leaky-bucket systems by about 30 %, in terms of conforming and non-conforming frames. Once various types of burst/silence traffic are generated, the leaky bucket is much better than other schemes by about 29 % in terms of utilization. Key-Words:Double leaky bucket , congestion, traffic shaping mechanism.