Traffic on your network must be protected. What is a stateful vs stateless firewall?
What Is Stateful vs Stateless Firewall?
A stateful firewall is a network security device or software program that monitors and filters the network traffic based on the data packets and their state. A stateful firewall is sometimes referred to as a connection-oriented firewall. Because it requires connections to be established before passing data between networks.
A stateless firewall is a network security device or software program. It monitors and filters the network traffic based on the data packets and their state. A stateless firewall is sometimes referred to as a packet-oriented firewall because it does not examine or care about connection information in the data packet.
Stateful inspection can identify protocol anomalies, such as an FTP command channel via HTTP, as part of its inspection process. Stateful inspection can also filter traffic based on Layer 7 information such as HTTP requests or FTP commands. It does not examine the header, nor does it examine the payload of packets.
Hence, it cannot filter certain types of traffic based on Layer 7 information such as HTTP requests or FTP commands.
Network Address Translation
Typically uses Network Address Translation (NAT) to allow multiple systems to share one public IP address. The NAT system translates private IP addresses into public IP addresses, enabling these systems to communicate with other computers on networks outside their local area network (LAN). This type of firewall is commonly used for Internet-based connections.
A stateless firewall does not use Network Address Translation (NAT). Instead, it uses Network Address Port Translation (NAPT). NAPT enables multiple systems behind a router or server to share one public IP address by creating multiple private addresses from a single public IP address.
A stateless firewall is particularly useful when implementing Virtual Private Networks (VPNs). It can also be used to enable several computers located behind an ISP’s proxy server to connect directly to the Internet.
Traffic Monitoring Firewall
A stateful firewall requires lesser configuration effort as all traffic can be blocked at once. A stateful firewall monitors all traffic crossing through it. It allows only legitimate connections to pass through the firewall.
It maintains an ongoing dialog between protected and unprotected computers. So, it keeps track of information about each protected computer on a list that is called an access control list or ACL. Also, it performs packet filtering based on IP addresses, ports, and protocols for each protected computer.
It controls access to networks or individual hosts using access control lists (ACLs). Also, it controls how much traffic is allowed to enter or exit a network. Monitor inbound and outbound traffic on an interface, to help ensure that unauthorized users do not try to exploit vulnerabilities in your system.
A stateful Firewall can also be configured to filter packets based on Layer 7 information such as HTTP requests or FTP commands. The main advantage of stateful inspection over stateless inspection is that the stateful method inspects both the header and payload of packets.