... high cost) firewalls have− − been developed, which can keep up with even the most demanding private networks. Some countries actually censor the Internet using high speed firewalls. − Firewalls ... functions that most firewalls support. Packet Filters The first Internet firewalls were simply packet filters, and packet filtering remains one of the key functions of today's firewalls. Filters ... to configure the firewall correctly. Most Windows based firewalls are easier to set up than Unix based firewalls, − − but many Unix based firewalls are catching up by using Java or web based graphical...