Delay performance of segmentation options for mixed packet networks

In many mixed-technology packet switching networks, segmentation is required to convert larger data units of one technology (e.g., frame relay) to data units of another technology (e.g., asynchronous transfer mode or ATM). This paper examines cut-through and non-cut-through segmentation and presents simulation results of delay performance for these two options for a network consisting of local access arrangements, frame relay network access links, and an ATM backbone network, cut-through segmentation is found to significantly reduce delays when the segmenter input blocks are large compared to the output segments and the segmenter input clock rate is small compared to other network rates. Cut-through segmentation also typically produces a less bursty output stream which improves queuing delay performance for all network traffic. In our sample network, the effect of the different segmentation options is found to be highly dependent on the local access arrangement