Popis: |
The aggregated traffic shaping per VP basis is analyzed. ATM promises integrity in services offered, efficiency in quantity (bandwidth) and quality (QoS) provided, and simplicity in implementation. The VP traffic shaping conveys ATM principles, especially simplicity. Due to its simplicity and flexibility, the leaky bucket is used to implement the VP shaper. The leaky bucket VP shaper and its detailed anatomy is presented. Its operation and performance evaluation are analyzed using queueing theory and simulated using OPNET. The simulation results clearly show the effectiveness of the leaky bucket VP shaper; cell loss probability is proportional to the sum of cell and token buffer size; and the Poisson approximation is true to the Bernoulli process when a large amount of traffic is aggregated while the input load is small. The practical implication of the discussion is in the appropriate choice of the parameter values of the leaky bucket VP shaper for design. |