摘要
双环网络作为一种具有实用性和可靠性的计算机网络已经被广泛研究，本文首先修正了［５］中的一个引理，然后给出了双环网络直径的一个显式表达式以及它的一些推论．
Double loop networks have ben widely studied as practical and reliable computer networkse In this Paper, we firstly improve a lemma in [1], then we give a directed formula on the dismeter of double loop networks. Some corollsries are also established.
