What is a Firewall?


Enhancing the security of your corporate data with firewall security is critical, however, you might be new to the term “firewall” and wonder how it can boost your network’s security. Read ahead and we will explain how extremely important a firewall is to network security and protecting your organization’s critical information.

Let’s be clear, the responsibility for network security is in your hands, but many business owners do not know how to keep their networks safe or simply do not prioritize it enough.

When your employees are logging into their computer, cloud applications, and email or transmitting data via email, you need reassurance that your corporate and customer data is safe and sensitive data won’t fall into the wrong hands.

Whether you run a small enterprise or business, it is important to provide a safe online experience. That is where the firewall comes into the picture. So, what is a firewall?


What is a Firewall?

What is Firewall

This term refers to a network security device that filters and monitors incoming and outgoing network traffic based on your organization’s established security policies. A firewall is an essential requirement if you want to boost your network’s security.

One of the most dangerous things anyone can do on a computer is access the internet without a firewall. It is your network’s first line of defense.

A firewall is a crucial barrier between the public internet and a private network. The firewall’s main objective is to permit only nonthreatening traffic and block any dangerous traffic from accessing and using your website.


What do Firewalls Do?

A Firewall is a critical part of any security architecture. It eliminates the guesswork out of host-level protections and passes them to your network security device. Firewalls, and NGFW (Next-Generation Firewall), aim to block application-layer and malware attacks. When used together with an integrated intrusion prevention system (IPS), these Next Generation Firewalls react quickly and seamlessly to detect and respond to external attacks across the whole network.

These firewalls can set policies to defend your network better and conduct quick assessments to detect suspicious or invasive activity, such as malware, and shut it down.


Why Do You Need a Firewall?


As we mentioned in the last section, Next Generation Firewalls block malware and conduct an application-layer inspection to prevent online attacks. Along with an integrated intrusion prevention system (IPS), Next Generation Firewalls react quickly and seamlessly to identify and counter attacks across the whole network.

When you leverage a firewall for your security infrastructure, you set up your network with specific policies to block malicious incoming and outgoing traffic. Without a firewall, the door left wide open for threats to come and go without any sort of filtration.


The Importance of NAT and VPN


Firewalls also perform essential network-level functions like Network Address Translation (NAT) and hosting a Virtual Private Network (VPN). Network Address Translation (NAT) translates or hides internal client or server IP addresses in a “private address range”. Hiding the addresses of such protected devices retains the limited number of IPv4 addresses. It becomes a defense against network reconnaissance because the IP address is invisible on the internet.

Also, a Virtual Private Network (VPN) extends a private network across a public network within a tunnel that is often encrypted where the contents of the packets are protected while traversing the internet enabling users to send and receive data across shared or public networks safely.

Types of firewalls

Firewalls can either be hardware or software, but it’s best to have both. A software firewall is a program you install on a computer to regulate traffic through applications and port numbers. In contrast, a hardware firewall is a piece of equipment you install between your network and gateway.

Packet-filtering firewalls examine packets and prohibit activities from passing through if they don’t sync with an established security ruleset. This type of firewall scrutinizes the packet’s destination, source, and IP addresses. If the packets match those “allowed” qualifications on the firewall, it is trusted and allowed to enter the network. Packet-filtering firewalls come in two categories: stateful and stateless. Stateless firewalls check packets independently of one another and have no context, making them easy targets for hackers. 

On the other hand, stateful inspection firewalls remember information about earlier passed packets and thus are considered much more secure.

Though packet-filtering firewalls can work effectively, they ultimately give very basic protection—for instance, they can’t determine if the content of the request being sent will negatively affect the application it’s getting to. For example, if a malicious request is allowed from a trusted source address, it will delete a database. In such a case, the firewall will have no way of knowing that. Proxy firewalls and Next-generation firewalls are more equipped to detect such threats.

Next-Generation Firewalls (NGFW) blend traditional firewall technology with additional technology, such as intrusion prevention systems, anti-virus, encrypted traffic inspection, etc. Notably, NGFW includes deep packet inspection (DPI). While basic firewalls look at packet headers only, deep packet inspection looks at the packet’s data; This enables users to more effectively categorize, identify, or stop packets with malicious data.

Proxy Firewalls filter your network traffic at the network application level. Unlike basic firewalls, this proxy becomes a mediator between two end systems. First, the customer has to send a request to the firewall. The request is then evaluated against a set of security rules and allowed or blocked. Proxy firewalls monitor traffic for network layer seven protocols such as FTP and HTTP and use deep packet inspection or stateful to detect malicious traffic.

Network Address Translation (NAT) firewalls permit multiple devices with independent net addresses to link to the internet using a single IP address. The process keeps individual IP addresses hidden. Thus, attackers scanning a network for IP addresses won’t capture specific details. This fact provides greater security against attacks. NAT firewalls resemble proxy service firewalls because they act as an intermediary between outside traffic and a group of computers.

Stateful Multilayer Inspection (SMLI) firewalls filter packets in the transport, network, and application layers. It compares them against known trusted packets. Similar to NGFW firewalls, SMLI examines the entire packet and allows them to pass if they pass each network layer individually. In addition, the firewalls scrutinize packets to know the state of the communication to ensure all initiated communication is taking place with trusted sources.


Where to Get High-Quality Network Firewall Services

If you are looking for reliable and credible firewall security services for your business, contact NGEN now. We are experts in network security. Our rates are affordable, and our services have given us a name in this industry. So, talk to us now and secure your data and earn the trust of your customers.