What is a Firewall and its Various Types
Because the number of cybercrimes is increasing, it is more vital than ever for individuals and businesses to take safeguards to safeguard their data. However, there are various impediments to doing the same. A firewall can help you safeguard your network and devices from potential invaders. This book will teach you all you need to know about firewalls and how they protect your network from intruders.
What is Firewall?
A firewall is a network security device that monitors and restricts the flow of data into and out of the network using predefined rules. A firewall is a security device that divides a private network from the rest of the Internet.
A firewall, like a fence around your house, prevents unauthorized people from entering your computer network. Firewalls are a form of network security technology that prevents attackers from entering the network. It is a device, either hardware or software, that checks and prevents data entering and leaving a private network for hostile activities.
Firewalls can be found in both commercial and residential networks. They are critical in keeping networks secure. Most operating systems feature a basic firewall. A separate firewall application, on the other hand, provides superior security.
Why Do We Need Firewalls?
Because it eliminates the need for manual setting of host-level security measures, a firewall is an essential component of any security architecture. Next-generation firewalls include an integrated intrusion prevention system (IPS), which enables them to identify and respond to external threats throughout the entire network, preventing malware and application-layer attacks. They may put policies in place to better safeguard your network and undertake rapid assessments to detect and stop dangerous or suspicious activity, such as malware.
Why are They so Important?
Next-generation firewalls, in particular, are built to protect against malware and application-layer attacks. These Next Generation Firewalls, when combined with an integrated intrusion prevention system (IPS), can respond to threats across the whole network quickly and reliably. Firewalls can undertake fast assessments to detect intrusive or suspicious activity, such as malware, and shut them down in accordance with predefined rules. By incorporating a firewall into your security architecture, you may manage what data enters and exits your system based on predefined criteria.
Types of Firewall
The following are the types of firewalls.
1. Packet filtering firewall
Firewalls that use packet filtering operate inline at nodes where other networking devices, such as routers and switches, operate. Rather than merely forwarding data, this sort of firewall examines the protocol headers of incoming packets to see if they fit the approved IP addresses, packet type, port number, and other criteria. When a malicious packet is found, it is normally discarded without further review, which means it is never delivered and thus never received.
While the security of packet filtering may fall short in some cases, it is worth exploring as a low-cost firewall solution in others. For enterprises with limited resources, packet filtering provides a low-cost yet effective security against typical internet threats. In larger organizations, packet filtering can be employed as a layer of defense to monitor department communications and block dangerous data.
2. Circuit-level gateway
TCP handshakes and other network protocol session initiation messages between local and remote hosts are monitored by circuit-level gateways across the network to determine whether the session is legitimate and the remote system is dependable. They do not, however, look inside the packages. While the security of packet filtering may fall short in some cases, it is worth exploring as a low-cost firewall solution in others. For enterprises with limited resources, packet filtering provides a low-cost yet effective security against typical internet threats. In larger organizations, packet filtering can be employed as a layer of defense to monitor department communications and block dangerous data.
3. Application-level gateway
This device, which is technically a proxy but is sometimes known as a proxy firewall, serves as both the network’s gateway and exit. Application-level gateways filter packets depending on other criteria, such as the HTTP request string, in addition to the service for which the packet was destined (as indicated by the destination port).
Gateways that filter at the application layer dramatically improve data security, but they can have a considerable impact on network speed and are not always easy to administer.
Application-layer firewalls are the best way to protect enterprise resources from online application dangers. They can prevent data leaks from within the firewall as well as restrict access to harmful websites. They may, however, cause a latency in communications transmitted and received.
4. Stateful inspection firewall
Sensitive hardware determines whether a particular packet is part of an active TCP or other network session, and it performs this check for each packet. More security is offered at the expense of network performance as compared to simply using packet filtering or circuit monitoring.
The multilayer inspection firewall is another type of stateful inspection that examines how transactions flow across several protocol layers of the OSI model’s seven-layer design. Most firms can benefit from a stateful inspection firewall. These devices allow a more complete link between computers and other assets within the enterprise firewall and the internet at large. They can also provide superior network node protection against specific attacks such as denial of service.
5. Next-generation firewall
A Next-Generation Firewall (NGFW) typically includes deep packet inspection (DPI), intrusion detection/prevention systems (IDS/IPS), malware filtering, and antivirus software.
DPI examines the data within a packet rather than the protocol header, as traditional firewalls do. A DPI firewall monitors data flow during a web browsing session, allowing it to identify whether or not the data in a packet payload, when coupled with data from other packets to form an HTTP server response, is valid HTML.
Read more Cyber Security blogs at iemlabs.com
