There are two main types of network firewalls, hardware, and software. Hardware firewalls usually have multiple physical network interfaces that can be used to create different security zones. In addition, these interfaces can be divided into subinterfaces, further expanding the protection zones. Hardware firewalls typically run on dedicated hardware appliances that handle thousands of connections and large volumes of packets. Software firewalls are software or host-based and control traffic on end-user workstations. This article will discuss the differences between each firewall type.
Open Source Software Firewalls
When comparing Open Source Software Firewalls, it is essential to consider the amount of technical expertise required to configure them. Many firewalls use command-line interfaces, so you must know how to use them. Fortunately, there are several ways to do so. If you have some experience in firewall configuration, this article may help you make an informed decision.
One benefit of open-source firewalls is their flexibility. You can install them on almost any type of hardware, virtual platform, or cloud. Some of the open-source firewalls even sell pre-configured appliances. Additionally, open-source operating systems have extensive security and networking capabilities. For example, most commercial firewalls are built on Linux. This allows you to select one based on your preferences and the size of your network.
Circuit-level gateways
A circuit-level gateway is a network firewall providing session-level control over network traffic. It works much like a packet-filtering router but at a higher layer in the OSI reference model protocol stack. It can filter the traffic without enforcing individual rules for each packet. It is an alternative to packet filtering routers but is not as effective because it cannot protect a network against malware and other data leaks.
A circuit-level gateway firewall works by intercepting a request from one computer to another. For example, computer A wants to view a web page from computer B outside of the firewall. The firewall intercepts and records the request before passing it on to computer B. Then, computer B sends the web page data to the IP address of the firewall. It then compares the IP address and port of the sending computer and allows the data.
Packet filtering firewalls
A packet-filtering firewall controls the flow of data in a network. It examines each packet for authenticity and compliance with pre-set rules, allowing or rejecting it based on these rules. It also checks ports and protocols. Each packet contains headers, which direct data to its destination. This is where the firewall gets its name. If any of the rules are violated, the firewall blocks the packet. Packet filtering firewalls provide the security and integrity of network data.
Another disadvantage of packet filtering firewalls is their inflexibility. For example, they use port numbers and IP addresses for authentication. Furthermore, they don’t remember past filtered packets, so they don’t improve over time. Additionally, the rules must be configured manually, which can lead to issues. But this isn’t a problem with most packet filtering firewalls.
Proxy-based firewalls
Proxy-based network firewalls are software that filter traffic on an application layer, which is Layer 7 of the Open Systems Interconnection model. They are helpful because they add an extra level of security by preventing packets from entering the system directly. A proxy server also acts as a gateway, forwarding a request to a remote computer, then receiving the answer. Proxy firewalls protect the network from external threats and keep internal web services and applications safe.
In addition, proxy firewalls obscure the inner architecture of a protected network. Because a proxy service disguises the network, the private IP address is kept from the outside community. In some cases, Network Address Translation (NAT) methods hide the IP addresses. This is standard practice for proxy firewalls. They also prevent packet leakage. Ultimately, proxy firewalls protect you from hackers. These are a good option for organizations concerned with cybersecurity.
Stateful multilayer inspection firewalls
Stateful Multilayer Inspection Firewalls are a type of security device that filters packets at the application, network, and session layers. These firewalls compare the contents of incoming data packets to known, friendly packets and allow only those connections to proceed. These firewalls are expensive and complex and are not as secure as other types of firewalls. Still, if properly maintained and administered, they can provide high levels of security.
Stateful inspection firewalls combine packet inspection technology with TCP handshake verification. By rejecting traffic between trusted interfaces, these devices can provide a higher level of security. But they can’t prevent application-layer attacks, which may not be detected or mitigated by stateful multilayer inspection firewalls. In addition, because other protocols do not have a well-defined state, they can’t scan for malicious data at the presentation layer.
Krishan Jangir