What is Firewall and Why do you need One ?


We often think what is best way to configure our computer to protect them against threats such as Trojan horses and worms . Many people will say that they have installed antivirus protection and never open unexpected attachment. But is that enough ? Antivirus protection is certainly an important part of an effective protection solution . It has the ability to detect known threats as well as many new ones via heuristic technologies .  But second technology that can be added to keep attackers or external threats from getting access to your system  in the first place is : Firewall 

What is Firewall ? 


Firewalls can be viewed as gated borders or gateways that manage the travel of permitted and prohibited web activity in private network . The term comes from the concept of physical walls being barriers to slow the spread of fire until emergency service can extinguish it . Comparably, network security firewalls are for web traffic management - typically intended to slow the spread of web threats.

Firewall create 'choke points' to funnel web traffic , at which they are then reviewed on a set of programmed parameters and acted upon accordingly . Some Firewalls also track the traffic and connection in audit logs to reference what has been allowed or blocked. Firewalls are one security tool in the broader category of user access control. These barriers are typically set up in two locations- on dedicated computers on the network or  the user computers and other endpoints themselves(hosts).

Why Do We Need Firewall ? 

You might already engage in certain safe computers and internet use practices, including these:

  • You don't click on unknown links or attachments.
  • You only log on to trustworthy, known websites 
  • You never give out out any personal information unless it is absolute necessary .
  • You have strong, unique, complex passwords for each online account that you often update.
Even with all this you are not safe . If you use internet , it's smart to have firewall in place. Cyberthreats are widespread and evolving. 

Here are the three main risk of not having firewall:
Without a firewall, you're accepting every connection into your network from anyone. You  wouldn't have any way to detect incoming threats . That could leave your device vulnerable to malicious user 

Not having firewall could leave your devices exposed , which could allow someone to gain control over your computer or network. Cybercriminals could delete your data. Or they could use it to commit identity theft or financial fraud 

Without a firewall , attackers could shut down your network. Getting it running again, and attempting to recover your stored data, could involve your time and money.

Types  Of  Firewall :

There are 5 types of Firewall  that continues to play significant role in enterprise and environment -

Packet filtering firewall : A packet filtering firewall is network security feature that controls the flow of incoming and outgoing network data. The firewall examinees each packet, which comprises user data and control information, and tests them according to set of pre-established rules. If the packet completes the test successfully , the firewall allow it to pass through its destination.

Circuit-level Gateway: A circuit-level gateway is a firewall that provides User Datagram Protocol (UDP) and Transmission Control Protocol (TCP) connection security, and works between an Open System Interconnection (OSI) network model transport and application layer such as session layer. It monitors TCP data packet handshaking and session fulfillment of firewall rules and policies.

Application Firewall: An application firewall is primarily used as an  enhancement to the standard firewall program by providing firewall services up to the application layer. Some of the services performed by an application  firewall include controlling the execution of applications , data handling , blocking malicious code from being executed and more. 

Stateful Inspection: Stateful inspection is a type of packet filtering that helps to control how data packets move through firewall. This type of assessment is also called dynamic packet filtering and represents a progression in how systems monitor packets in order to prevent dangerous incoming traffic from getting through firewall technologies.

Next Generation Firewall: Next generation firewall are a class of firewall that are implemented in either software or hardware and are capable of detecting and blocking complicated attack by enforcing security measures at the protocol , port and application level. It performs more in depth inspection and in smarter ways .


As the cybersecurity landscapes continues to evolve and attacks becomes more sophisticated , Firewalls will continue to be an essential components of an organizations security solution , whether you are in data center , network or cloud.