Measuring Performance Impact of Security Protocols in Wireless Local Area Networks

In this paper, we study and quantify the impact of the most widely used security protocols, such as 802.1x, EAP, IPSEC, SSL and RADIUS, in wireless local area networks (WLANs). Based on the measurements in a wireless network testbed, we present quantitative, realistic findings with regards to both security functions as well as network performance. First, we describe experimental setup including system configuration and protocol stack. Then, we consider a variety of individual and hybrid security policies in order to capture the impact of security services at different network layers. Moreover, depending upon mobile nodes' current location, user mobility is categorized into non-roaming and roaming scenarios. In addition, we define several performance metrics such as authentication time, authentication messages, response time, throughput to measure the overhead associated with security policies on system performance. Comprehensive experimental measurements and analysis are provided for TCP/UDP traffic streams and network variations to demonstrate the impact of security protocols in WLANs.