Virtual channels have been introduced to enhance the performance of worm hole-switched net- works. They are formed by arranging the buffer space dedicated to a given physical channel into multi-ple parallel buffers that share the physical bandwidth on a demand driven time-multiplexed manner. The question to be answered is given a fixed amount of finite buffer what is the optimal way to arrange it into virtual channels There have been few studies attempting to address this issue, however, these stud- 1es have so far resorted to simulation experiments and focused on deterministic routing algorithm s. In this paper we use analytical performance models to investigate the optimal arrangement of the available buffer space into multiple virtual channels when adaptive routing is used in worm hole-switched k-aryn- cubes.