Fault tolerant communication performance of BCCC data center networks based on disjoint paths

To satisfy the requirements of various application scenarios, data center networks with higher computing power, faster processing speed, and larger storage space have been proposed. As a server-centric data center network, BCube connected crossbars (BCCC) has significant advantages in terms of expandability, communication latency, and robustness in component failures to ensure better network performance. The switches of BCCC only serve as crossbars, so we focus on the interconnections among servers, and the logical graph of BCCC is denoted as L-BCCC. With the expansion of network scale, failures are inevitable, and it is imperative to maintain reliable communication and reduce communication delay in the event of failures. In this work, we investigate the fault tolerant communication performance of L-BCCC with respect to disjoint paths. First, we devise an O(k³+nk²) algorithm to construct $n+k-1$ disjoint paths (i.e. as many paths as the connectivity) between any two distinct nodes in L-BCCC$(n, k)$, where the maximum length of the path is only 3 larger than the diameter. As a by-product, we determine the connectivity of L-BCCC$(n, k)$. In addition, we also investigate the $(n+k-1)$-wide diameter and $(n+k-2)$-fault diameter of L-BCCC$(n, k)$, which are close to the diameter of the network. Finally, the fault tolerant routing based on the constructed disjoint paths is evaluated by simulation experiments to have good and stable transmission performance in case of node failures.