Optimal Gossiping on CCCs of Even Dimension

A heuristic has shown that the results achieved by earlier algorithms for gossiping on cube-connected-cycles (CCCs) in the unit-cost telephone model were not optimal, but no general pattern was revealed. In this paper new gossiping algorithms are presented that apply to CCCs of all sizes. Most importantly, we show that for gossiping on the "k-dimensional" network, CCCk, with k even, gossiping can be performed in 5/2 · k - 2 communication rounds, which exactly matches the lower bound, thus completely solving the gossiping problem for these networks. For odd k we improve upon the best previous algorithm without matching the lower bound.