If, for instance, an attachment sets out to delete files, SurfinGuard would not run the program. Finjan claims SurfinGuard causes performance degradation. Users can also consider employing a personal firewall. Personal firewalls, such as NFR's BackOfficer Friendly or the free ZoneAlarm, monitor incoming and outgoing network traffic similar to the way network firewalls do. Firewall software will also pop up and say a machine has been scanned.
Port scanning is a common tool hackers use to detect clear and open paths into a network.
But in an environment where systems administrators remotely update and manage an agency's desktops, a personal firewall could cause some problems, Bair says. We should never put the corporation at risk just for individual convenience. Bair advocates a standardized desktop configuration that prohibits users from loading their own programs. This could help agencies avoid dangerous programs innocently downloaded from the Internet. Part of this strict regimen is disabling a number of features that accept programs that are popular with hackers and virus writers.