Traditional firewalls control traffic entering and exiting a network using stateless or stateful methods. Next-generation firewalls combine traditional firewall features with additional capabilities like deep packet inspection, intrusion prevention, and application awareness. While traditional and next-generation firewalls both provide static packet filtering and stateful inspection, next-generation firewalls offer more advanced protection through deep packet inspection at the application level and integration of outside threat intelligence. The document compares features of leading next-generation firewall vendors Cisco, CheckPoint, Fortinet, WatchGuard and Dell.