SMLI firewalls are different from the conventional
The SMLI firewalls are different from the conventional "stand in" proxies in a way that the stand-in proxies are used for the applications when communicating to the outside world, thus putting a heavy processing load on the processors. In contrast, the SMLI firewall just examines each packet and compares them against the known states (i.e. bit patterns) to know about the behaviour pattern of the acceptable packets.