Just about every type of organization today has a sustained presence throughout the Internet. If this applies to you, then you likely have a network connection to your business somehow. These can be vulnerable to outside attacks, which speaks to the importance of having a plan in place for network security. Firewall security must also be taken into account in order to keep unauthorized parties out and your information safe.


Types of Firewalls

A network firewall is designed to isolate the internal network in your organization from prying eyes outside. It helps to prevent unauthorized access to your system. There are various types of firewall security, and those are briefly explained below.


Stateless and Stateful

This is a type of firewall that allows your internal network to be connected to the Internet by way of a router firewall. This router will then inspect and filter out data as it comes in.


Application Gateways

Gateways effectively perform the function of a relay station for traffic attached to an application. They will intercept packets that are coming in and going out to ensure that they are not meant to do harm to your system.


Application Specific

This is a type of proxy that will only accept packets of data that are generated by the specific application that they are designed to copy, forward, and filter traffic for.



With this type of proxy gateway, your firewall will be examining and filtering out individual packets, as opposed to only copying them and sending them on across the gateway. The contents of the packet will first need to be verified.



A transparent gateway will require that a user is authenticated before they can access a network that is not yet trusted. This type of authentication may vary depending on if the user is inside the network or accessing it from the Internet.


Circuit Level Gateway

Here you have an intermediate solution that works by combing the packet filter process and the application gateway. This can provide you with a proxy for virtually any application that you run.



This actually refers to a type of circuit level gateway that acts as a networking proxy to enable the host on one side of the server to access the hosts on the other side. This is done without needing the IP to be reached directly.


Firewall Deployment

Deployment of a firewall entails controlling traffic that comes in and out of the internal network. Most organizations will have two different interfaces. One will deal with the internet and other types of external networks, while the other one deals with the internal network.


Intrusion Detection

This type of system goes a step further than packet filtering firewalls by carrying out a Deep Packet Inspection. This means that the firewall will look for character strings within a packet to determine if there is a known virus there.


IDs and IPs

These both work to detect certain anomalies that are present in the network. An IDS is a tool that is visible, while an IPS is more of a control tool to keep. Unauthorized users out of the system.


Types of IDs

The two main types of IDS are signature based and anomaly based. A signature-based IDS requires a database that contains known attacks along with their signatures. An anomaly-based IDS actually develops a traffic pattern that relates to standard network operation.

The specific type of network firewall that you implement into your security plan will depend on the nature of your organization. The key is to make sure that your data is secure and that only authorized people can gain access to it. You will want to stay vigilant in this regard, as threats to network security are only likely to increase in the coming years.