Bandwidth gain is a measure of the effective increase of server bandwidth resulting from the client’s use of a ProxySG. For example, a bandwidth gain of 100% means that traffic volume from the ProxySG to its clients is twice as great as the traffic volume being delivered to the ProxySG from the origin server(s). Such bandwidth gain is one of the advantages of using a ProxySG. Given the SG’s focus on page response time and object freshness, the increased bandwidth gain may not be at the maximum. Bandwidth Gain mode can improve the already better bandwidth gain by letting you override certain settings. Using Bandwidth Gain Mode can provide substantial gains in apparent performance.
Keep in mind that bandwidth gain is a relative measure of the ProxySG’s ability to amplify traffic volume between an origin server and the clients served by the SG.