Firewall – The First Line of Defense For Your Network
Firewall is the first line of defense for your network.
A firewall is a security system that monitors and controls the flow of data both in and out of your network based on a set of pre-determined rules. This allows legitimate traffic to enter and leave the network while blocking any malicious activity that could threaten its integrity, cause data loss or launch cyberattacks.
Think of the firewall as a security guard that watches all the activities in the building (network) it is protecting and verifies that the security of all who want to enter it are appropriate. Firewalls protect networks at home, work or in public from hackers who can gain access and steal sensitive information, corrupt systems, crash systems or initiate a Man-in-the-Middle attack.
Firewalls are a crucial part of every business and are used in all types of organizations. There are many different firewall products available to help keep the business safe. Each type has different features, but each uses the same core technology. Each firewall operates at a different level of the standardized communications model, the Open Systems Interconnection (OSI) Model.
The first firewall technology to be widely deployed was the circuit-level gateway. It works at the session OSI layer and verifies TCP handshakes to grant or deny access. It requires minimal resources and does not inspect packet payloads, but it is susceptible to IP spoofing attacks. This type of firewall was followed by stateful inspection and then next-generation firewalls (NGFW). NGFWs combine traditional firewall capabilities with application awareness and an intrusion prevention system (IPS) to create a single solution that is able to better protect the modern network perimeter.