A firewall is a network security device or application that monitors incoming and outgoing network traffic and decides whether to allow or block specific traffic based on a predefined set of security rules. A firewall can be hardware, software, or both.
Firewalls are designed for both single computer and for a network. Host-based Firewall and Network-based Firewall. A host-based firewalls are inbuilt or third-party application installed on individual workstation or servers and monitors incoming and outgoing activities. A network-based firewall could be a hardware, application or both. A network-based firewall can be installed on administrator’s system for monitoring incoming and outgoing activities between computers in the network.
Types of Firewalls:
Types of firewalls are include:
Packet-filtering firewalls, Stateful inspection firewalls, Proxy firewalls, Unified threat management (UTM) firewall and next-generation firewalls (NGFW).
- A packet-filtering firewall examines each every packets that pass in the network. Packet-filtering firewalls work at the Network layer of the OSI networking model. k. Packet-filtering firewall examines the packet headers that contain IP addresses and packet options and block or allow traffic depending on the set of rules in the firewall configuration.
- A Stateful inspection firewall allows or blocks traffic based on state, port, and protocol. It monitors all activity from the opening to the closing of a connection. Filtering and motioning are made based on set of rules.
- A proxy firewall works at the application layer of the Open Systems Interconnection (OSI) reference model.
- Unified threat management (UTM) firewall. UTM Firewall is combined along with other security services in UTM Router. It provides multiple security features and services in a single device or service on the network, protecting users from security threats in a simplified way. UTM functions and services also include anti-virus, anti-spam, content filtering, and web filtering.
- An NGFW uses a multilayered approach to integrate enterprise firewall capabilities with an intrusion prevention system. Most companies are deploying next-generation firewalls to block advanced threats like malware and application-layer attacks.
Best Free Firewall:
Both Host-base and network-based firewall configuration is necessary in a computer network. Check on network security for more information about firewall and other security mechanism necessary for securing an individual computer and the entire network.