Congestion Control Method Study On ATM Network

The transmission method of ATM belongs to fast packet switching mode, and it provides several services such as voice, video and data. The pol icy to control the congestion of ATM differs from those of other networks. In this paper, ATM congestion control theory and its particularity are given, optimal control algorithm, LQG stochastic control algorithm and an algorithm put forward by the author to resolve ATM cell congestion, are introduced. The deployment of this paper is following:First, improves an optimal algorithm, and applies the modified algorithm to the congestion control problem of single ATM node whose bandwidth is invariable. We program this algorithm and ERICA, and the result shows that the improved algorithm has better performance than ERICA.Second, ATM transmits voice, video, and data at the same time, some bandwidth is reserved for CBR cells and VBR cells because voice and video cells have high priority, and thus the bandwidth available to ABR cells is variable. Take the above factors into consideration, the improved optimal algorithm is modified to LQG stochastic control algorithm for single ATM switching node whose bandwidth is variable. Both C and matlab simulation have been done, and we find that the stochastic control approach is preponderant, especially in controlling queue length of the switch node. In addition, it is easy to apply the stochastic algorithm to the switch for its simplicity.Third, this paper brings forward a rate allocation algorithm inAbstractthe case of multi-source and multi-destination transmit through multi switch. Considering complexity and correlation between variables, we decide to adopt genetic algorithm to the optimization. For a given network, we analyze and design the flow chart of implementing the algorithm in detail.