What is a Firewall?
Firewall is a cybersecurity solution that creates a barrier between your system and external sources. It examines data packets at the network level and filters them based on their origin and destination. It blocks any suspicious packets from entering your internal systems and prevents cybercriminals from stealing your internal data. A firewall also prevents your network users from accessing outside websites, preventing them from browsing sites with malware or other dangerous contents.
Originally, firewalls were physical hardware appliances that were plugged into a company’s networking infrastructure. Later, they became software applications and can now be run virtually in the cloud. Some companies also contract managed security service providers to host their firewalls for them. Firewalls have evolved over the years with newer generations adding stateful and application-layer inspection capabilities.
Packet-filtering firewalls assess data packets that are coming from and going to a router or switch. They analyze the data packets at the OSI network layer and filter them based on the source IP address, the destination IP address, and the packet type. They also assess the byte-level content of the packet to look for malicious codes.
In the same way that a fire wall limits damage from a fire, firewalls limit the damage done by hackers by inspecting traffic incoming and outgoing byte by byte. Firewalls are an essential part of any cybersecurity solution. In the future, you can expect them to become even more effective and dependable. Simplilearn’s Cybersecurity bootcamps like CEH v11 – Certified Ethical Hacker (V11) can teach you how to build and deploy firewall solutions for your clients.