A stand-alone device used to provide security for a network. See firewall appliance and network appliance. THIS DEFINITION IS FOR PERSONAL USE ONLY. All other reproduction requires permission.

Network security vendors sold about $301.6 million in appliances through the channel in the second quarter, down from $309.6 million in the same period a year ago, according to The NPD Group.

Perimeter security appliances and devices, particularly VPNs, prove to be the most popular entry points into victim networks for financially-motivated ransomware gangs, according to reports.