A method for improving the reliability and performance of Vehicle-to-Vehicle (V2V) networks where digital certificates are necessary for message authentication and some messages may be lost in transmission. The method uses a variable inter-certificate refresh period to optimize communications throughput based on network conditions such as node density and bandwidth saturation. In some network conditions, the inter-certificate refresh period may be increased, such that more certificate digests are sent between full digital certificates, to decrease average message size. In other network conditions, the inter-certificate refresh period may be decreased, to allow for more frequent message authentication by receiving nodes. Empirical data and an adaptive controller are used to select the refresh period which will provide the best performance based on network conditions.