Are you looking for the best firewall to protect your business against potential threats? You can make the right decision by understanding how firewalls function. This article will help you make educated decisions about the different types of firewalls.
What is a Firewall?
A firewall is a security device that monitors network traffic. The firewall protects your internal network by filtering outgoing and incoming traffic according to a set of rules. A firewall is the easiest way to add security between a system’s network and malicious attacks.
How Does a Firewall Work?
To protect a system from malicious traffic, a firewall is installed on its hardware or software levels. It can be used to protect one computer or the entire network. The device inspects incoming and incoming traffic in accordance with predefined rules.
The Internet allows you to communicate by asking for and sending data from one sender to another. Data cannot be sent in one piece so it is broken down into manageable data packets which make up the originally transmitted entity. A firewall’s role is to inspect data packets that are being sent to and from the host.
What is a firewall supposed to inspect? Each data packet contains a head (control information), and a payload(the actual data). The header contains information about the sender as well as the receiver. The firewall must be passed before the packet can be allowed to enter the internal network via the designated port. The information the packet carries and the way it matches the predefined rules will affect the speed of the transfer.
A firewall could have a rule that blocks traffic from certain IP addresses. The firewall will deny access to data packets containing that IP address in their header if it receives them. A firewall can also deny access to any person except those who are trusted. This security device can be configured in many ways. The type of firewall determines how much it protects the system.
Also read: What is DNS Port and How to allow DNS through Firewall
Different Types of Firewalls
While they all serve to prevent unauthorized access, There are many ways to operate firewalls. There are three types of Firewalls – Software firewalls, hardware firewalls or both This list identifies the remaining types of firewalls and these firewall technologies can be used as hardware or software.
A software firewall is installed on the host device. This type of firewall is also called a Host Firefox. It is required to use the resources of the device it is attached to in order to function properly. It is therefore inevitable that it will use some of the system’s CPU and RAM.
You will need to install the software on each of your devices if you have multiple devices. It must be compatible with the host so each one will require a different configuration. The main problem is the amount of knowledge and time required to manage and administer firewalls for each device.
Software firewalls, on the other hand, can identify different programs and filter outgoing and incoming traffic. They can allow access to one program and deny it to another.
As the name suggests, Hardware firewalls are security devices that act as a separate pieces of hardware between an internal network and an external network (the Internet). This type of firewall is also called an Appliance Firewall.
Is not like a software firewall. A hardware firewall has its own resources and does not consume CPU or RAM from host devices. It’s a physical appliance that acts as a gateway to traffic that passes between internal networks.
They can be used by large and medium-sized organizations. that have multiple computers that can be connected to the same network. In such cases, it is more practical to use a hardware firewall installing individual software on each device. Knowledge and skills are required to configure and manage a hardware firewall So make sure you have a competent team that can take on this responsibility.
Types of firewalls, based on the method of operation, the most basic type of firewall is the packet-filtering firewall. It acts as an inline security checkpoint attached to a router or switch. As the name suggests, It monitors network traffic and filters incoming packets based on the information they contain.
Each data packet is composed of a header as well as the data it transmits, as explained previously. Based on the header information, this firewall determines whether a packet can be allowed or denied access. It inspects the protocol, source IP address, and destination IP. The source port and destination ports are also checked. The access control (rules that define wanted/unwanted traffic) determines whether packets will be passed on or dropped.
A data packet that doesn’t meet all requirements will not be allowed to enter the system.
A packet-filtering firewall can be a quick solution and doesn’t take up much of your resources. It is not the most secure. It only inspects header information. However, it does not check the payload data. The packet-filtering firewall may not be the best choice for system security because malware can also be found within this section of the data packet.
Circuit-level gateways can be described as a firewall that works at the session layer in the OSI model. They observe TCP ( Transmission Control Protocol ) connections and sessions. They are responsible for ensuring that established connections remain safe.
Circuit-level firewalls are usually built into some type of software or an already existing firewall.
They are similar to pocket-filtering firewalls in that they do not inspect the actual data, but only the information about transactions. Circuit-level gateways are also practical and simple to set up and don’t require a separate proxy server.
Stateful Inspection Firewalls
A stateful inspection firewall to keep track of the connection by monitoring the TCP 3-way handshake. It can keep track of all connections, from beginning to end, and allow only expected return traffic inbound.
The stateful inspection creates a database (state table) when a connection is established and requests data. It also stores connection information. It records the connection information, including the source IP, destination IP, and destination ports. It dynamically creates firewall rules for traffic anticipated by using the stateful inspection method.
This firewall provides additional security. This type of firewall is used as an additional security measure. It has more checks and is safer than stateless filters. Stateful firewalls, however, inspect all data transmitted over multiple packets, not just headers, and are therefore more reliable than stateless/packet filters. They also consume more system resources because of this.
Also read: 10 Best Linux Firewall Solutions
Proxy firewalls act as intermediaries between internal and external systems that communicate over the Internet. It forwards requests from the original client to protect the network and then masks them as its own. A proxy is a proxy that acts as a substitute. It acts as a substitute for the client who is sending the request.
The proxy server intercepts the client’s request to access a website page. The proxy server pretends to be the client and forwards the message to a web server. This hides the identity and geolocation of the client, which protects it from possible attacks and restrictions. The proxy receives the requested information from the web server, and the proxy responds to it.
The next-generation firewall is an integrated security device that includes many functions from other firewalls. It includes packet, stateful and deep packet inspection. NGFW inspects the payload of each packet, rather than focusing on the header information.
The next-generation firewall, unlike traditional firewalls, inspects all data transactions, including TCP handshakes and deep packet inspection.
NGFW provides adequate protection against malware attacks, intrusion, and external threats. These devices are quite flexible, There is no clear definition of what functionalities they offer, and make sure to explore each option to find out more
A cloud firewall or firewall-as-a-service (Faas) is a cloud solution for network protection. It is managed and operated on the Internet by third-party vendors, just like other cloud solutions.
Cloud firewalls are often used by clients as proxy servers. However, the configuration can be modified to meet client needs. They are very scalable. They can scale the firewall capacity according to the traffic load and are independent of physical resources.
This solution is used by businesses to protect their internal networks or other cloud infrastructures (Iaas/Paas).
Which Firewall Architecture Is Right for Your Business?
There is no need for you to be specific when choosing a firewall. Multiple firewall types provide multiple layers of protection.
Consider the following:
- The organization’s size: The internal network’s size. Do you need to manage firewalls on every device or a firewall that monitors your internal network? These are the key questions to consider when choosing between hardware and software firewalls. The tech team responsible for managing the setup will also play a significant role in deciding between the two.
- The available resources: The budget. Can you afford to put the firewall on its own piece of hardware, or on the cloud? It is important to consider the traffic that the firewall must filter and whether it will be consistent.
- The required level of protection: The types and number of firewalls that are required by the internal network should be reflected. A business dealing with sensitive client information needs to ensure data is protected from hackers by tightening firewall protection.