Information, Computer and Network Security Terms Glossary and Dictionary

Network Layer Firewall

Network layer firewall is a type of firewall that works as a packet filter by deciding what packets will pass the firewall according to rules defined by the administrator. Filtering rules can act on the basis of source and destination address and on ports, in addition to whatever higher-level network protocols the packet contains. Network layer firewalls tend to operate very fast, and transparently to users. Network layer firewalls generally fall into two sub-categories, stateful and non-stateful. Stateful firewalls hold some information on the state of connections as part of their rules. Stateless firewalls have packet-filtering capabilities but cannot make more complex decisions on what stage communications between hosts have reached. Stateless firewalls therefore offer less security.

Related Terms

Network Layer Firewall