{"id":1178,"date":"2024-10-22T03:23:25","date_gmt":"2024-10-22T03:23:25","guid":{"rendered":"https:\/\/www.extnoc.com\/blog\/?p=1178"},"modified":"2025-09-19T10:17:32","modified_gmt":"2025-09-19T10:17:32","slug":"the-different-types-of-firewall","status":"publish","type":"post","link":"https:\/\/www.extnoc.com\/blog\/the-different-types-of-firewall\/","title":{"rendered":"Different Types of Firewalls in Network Security Explained"},"content":{"rendered":"

What is Firewall and its Types?<\/h2>\n

A firewall is a network security device that monitors network traffic. The standard firewall definition shows that firewalls are systems that are put in place to provide network security<\/a>. It does this by filtering out both in and outgoing network traffic \u2013 based on rules defined by the user. They reduce and in some cases, eliminate the occurrence of unwanted communications in the network, and at the same time, allow any genuine communication and information to flow in and out freely. Types of Firewall aren\u2019t an option \u2013 they are essential for any business. They work hard to prevent attackers from accessing your servers and data maliciously.<\/p>\n

5 Different Types of Firewall and Architectures<\/span><\/h2>\n
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Did you know that there are eight different types of firewall? Firewalls have different uses, and it depends on why you are using one to decide which type you should have for your business. Let\u2019s go over the different types of firewall:<\/span><\/p>\n

Packet-Filtering Firewalls<\/span><\/h3>\n

Packet-filtering firewall is the oldest firewall type out there. They are designed to create checkpoints at individual routers or switches. The packet-filtering firewalls will check the data packets that try to come through, without inspecting the contents. If the information trying to come through looks suspicious, it cannot get through the network. This is a simple firewall that does not impact network performance too much.<\/span><\/p>\n<\/div>\n

\"CTA\"<\/a><\/div>\n<\/div>\n

Circuit-Level Gateways<\/span><\/h3>\n

Circuit-level gateways are much like packet-filtering firewalls in that they quickly and easily check and approve or deny traffic. They do it without being heavy on resources, too. Circuit-level gateways<\/a> work by verifying the transmission control protocol handshake. It doesn’t check the packet directly, so there is a risk of malware getting through. These are not the best ones to protect your business.<\/span><\/p>\n

Stateful Inspection Firewalls<\/span><\/h3>\n

A combination of the two firewalls above, the stateful firewall inspection offer a higher level of protection for your business. The problem with these is that they take up more resources, which can slow down the legitimate packet transfer.<\/span><\/p>\n

Proxy Firewalls (Application-Level Gateways\/Cloud Firewalls)<\/span><\/h3>\n

A proxy firewall operates at the application layer as a middleman to filter incoming traffic between an end system and another end system.<\/p>\n

If you want firewalls that operate at the application layer to filter traffic, proxy firewalls do the job. These are cloud-based most of the time, and they establish traffic connections and examine data packets coming through. The difference between these and the stateful inspection firewalls is that the proxy firewalls can also do a more in-depth inspection to check the packet contents. The drawback to these is that they can create a <\/span>\u00a0network slowdown<\/span><\/a> because of all the extra steps – but it\u2019s all in the name of the security for your business.<\/span><\/p>\n

Next-Generation Firewall<\/span><\/h3>\n

There\u2019s no real insight into what makes a firewall today \u201cnext-generation\u201d besides the time it was created. There are commonalities between these firewalls and the originals, and those include TCP handshakes and packet inspections. Next-generation firewalls also use IPS – intrusion prevention systems – to stop network attacks.<\/span><\/p>\n

Pros and Cons of Different Types of Firewalls<\/h2>\n

Here is a comparative table of the pros and cons of different types of firewalls:<\/p>\n\n\n\n\n\n\n\n\n
Type of Firewall<\/th>\nPros<\/th>\nCons<\/th>\n<\/tr>\n
Packet Filtering Firewalls<\/td>\n\n
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  • Simple and fast<\/li>\n
  • Low resource consumption<\/li>\n
  • Basic filtering based on IPs, ports, protocols<\/li>\n<\/ul>\n<\/td>\n
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  • Limited security features<\/li>\n
  • Cannot inspect payload data<\/li>\n
  • Vulnerable to IP spoofing<\/li>\n<\/ul>\n<\/td>\n<\/tr>\n
Circuit-level Gateways<\/td>\n\n
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  • Efficient at filtering TCP handshakes<\/li>\n
  • Protects at session level<\/li>\n
  • Lightweight and low cost<\/li>\n<\/ul>\n<\/td>\n
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  • No deep inspection of packets<\/li>\n
  • Cannot filter specific application data<\/li>\n
  • Limited logging<\/li>\n<\/ul>\n<\/td>\n<\/tr>\n
Application-level Gateways<\/td>\n\n
    \n
  • Provides deep packet inspection<\/li>\n
  • Can block specific applications<\/li>\n
  • Stronger access control<\/li>\n<\/ul>\n<\/td>\n
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    \n
  • Slower due to in-depth inspection<\/li>\n
  • Resource-intensive<\/li>\n
  • Requires configuration per application<\/li>\n<\/ul>\n<\/td>\n<\/tr>\n
Stateful Inspection Firewalls<\/td>\n\n
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  • Tracks state of active connections<\/li>\n
  • More secure than stateless filtering<\/li>\n
  • Can filter based on context<\/li>\n<\/ul>\n<\/td>\n
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  • More resource-intensive than packet filtering<\/li>\n
  • Vulnerable to certain DoS attacks<\/li>\n<\/ul>\n<\/td>\n<\/tr>\n
Next-generation Firewalls<\/td>\n\n
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  • Combines multiple filtering methods<\/li>\n
  • Intrusion detection and prevention<\/li>\n
  • Application-level control<\/li>\n<\/ul>\n<\/td>\n
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