My iRule Impressions & Optimiziation-Request-"Contest" (IP to STOREID)

A couple things come to mind. Move the math into CLIENT_ACCEPTED since that occurs only once during the session, the scan & expression alone took 130000 cycles in a quick test I just ran. Also, unless you are eventually going to derive the net values dynamically, just use them directly and avoid setting the variables (net_start, net_mask, net_segment_mask). Make your next net_start if an elseif so it is not checked if the first is evaluated.