Architectural impact of secure socket layer on Internet servers

Abstract

Secure socket layer (SSL) is the most popular protocol used in the Internet for facilitating secure communications. In this paper, we analyze the performance and architectural impact of SSL on the servers in terms of various parameters such as throughput, utilization, cache sizes, cache miss ratios, number of processors, control dependencies, file access sizes, bus transactions, network load, etc. The major conclusions from this study are as follows: The use of SSL increases computational cost of the transactions by a factor of 5-7. SSL transactions do not benefit much from a larger L2 cache, but a larger LI cache would be helpful. A complex logic for handling control dependencies is not useful for SSL transaction as the frequency of branches is very low. Because SSL workload is highly CPU bound, it may be possible to enhance SSL performance by using a number of other architectural features as well.