A comparison of three switching schemes in isotropic networks with noisy channels

Previous work on analyzing three switching schemes for isotropic networks, namely single hop and two cut-through communication schemes (with and without error checking by intermediate nodes), is extended. Each scheme is modeled by a discrete Markov chain. It is shown how the performance of the communication schemes depends on path length (n ), load on the network (λ), and the error rate (p). As expected, the cut-through schemes perform much better than the single hop when the communication load is light, but as the load increases, the cut-through schemes deteriorate more rapidly, until they are comparable. In fact, when the load approaches saturation (λ is close to 1-p), the cut-through schemes are actually worse than the single-hop schemes. The schemes with checking always outperform those without, but each node must perform more work in checking the correctness of the packets passing through. The time delay becomes infinite when the throughput approaches 1-p. The solutions are expressed as simple formulas and/or algorithms for each scheme