In the world of computing, firewall is a firmware or software which enforces rules regarding the data packets why they are allowed to go in or left the network. It is incorporated in a huge range of networked devices in order to lower risk of nasty packets that are impacting the private network' security and filter traffic. Firewalls can be bought as separate software applications.
Firewall is basically a metaphor which compares physical barrier used to limit harm a fire might cause. It is a virtual barricade which is used to limit the harm caused due to internal or external cyberattack. Besides, firewalls offer low network protection, and auditing and logging functions.
Majorly, there are two types of firewalls - network-based and host-based. Network-based firewall is built on the cloud or it could be virtual firewall and host-based firewall can be installed on the individual monitors and servers.
Other Kinds of Firewalls -
The list of other firewalls include proxy firewalls, packet-filtering firewalls, next-generation firewalls, and stately inspection firewalls.
-- Packet-filtering firewall inspects isolation in the packets and have no idea about the content in packet.
-- Stately inspection firewall inspects network traffic in order to control whether a packet is connect to other packet or not.
-- Proxy firewall examines the packets at app layer of OSI - Open System Interconnection reference model.
-- Next-generation firewall utilizes multilayered approach for the integration of business firewall abilities with application control and IPS - Intrusion Prevention System.
-- When the businesses start moving from the mainframe computer and irritated clients to client-server model, then at that point of time having a control access of server became necessary. The very first firewalls established in late 1980s and just real network security was imposed via ACLs lists. The work of ACLs is to specify which IP address denied or granted access on network.
-- Increasing internet growth and increase the connectivity of the network means the filtering of network traffic via IP address particularly is not enough. Hence, packet-filtering firewalls used to inspect packet headers and also to come on conclusions has become the vital part of each network security by last century.