A Study of the Performance of SSL on PDAs

PDAs and smart phones are increasingly being used as handheld computers. Today, their network connectivity and their usages for various tasks over the Internet require privacy and authenticity. In this paper, we conduct a comprehensive and comparative study of the performance of the SSL protocol for PDA and laptop clients, both in WEP secured and open Wi-Fi environments. Unlike previous studies [1], [2], the measurements are at sub-protocol granularity allowing for researchers to consider appropriate optimizations for these resource-constrained devices. Unsurprisingly, we find that SSL handshake costs 3 times more at a PDA client than it does for a laptop client, but surprisingly most of the delay comes from network latency and other PDA architecture issues, not cryptographic computation. This suggests that more effort should be spent in minimizing communication rounds in future cryptographic protocols that will be used by PDAs, even at the cost of more cryptographic operations.