Firewalls can be either hardware or software. In addition to limiting access to a protected computer and network, a firewall can log all traffic coming into or leaving a network, and manage remote access to a private network through secure authentication certificates and logins.
- Hardware firewalls: These firewalls are released either as standalone products for corporate use, or more often, as a built-in component of a router or other networking device. They are considered an essential part of any traditional security system and network configuration. Hardware firewalls will almost always come with a minimum of four network ports that allow connections to multiple systems. For larger networks, a more expansive networking firewall solution is available.
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