Stateful Firewall : Stateful Firewalls are equipped to monitor and detect the state of all traffic that is on the network. They can track and defend based on traffic flow patterns, and a Stateful firewall is aware of connections that go by it.
It adds and keeps details about the connections of users in a state table, also called the connection table. It then utilizes this connection table to establish security policies that apply to the connections of users. Examples of stateful firewalls are: Juniper, ASA, and Checkpoint.
Stateless Firewalls : Stateless firewalls concentrate on specific packets and use preset rules to filter traffic. Stateless firewalls, however, do not examine the status of connections; instead, only at the packets. An excellent example of a filtering firewall is the Extended Access Control lists available on Cisco's IOS Router.
