N/APosted on - 11/29/2014
What are the different types of firewalls available? How would you differentiate firewalls based on where they intercept the communication? What is a virtual firewall? Differentiate between a virtual firewall operating between a bridge mode and other operating in the hypervisor mode. What is a personal firewall? How is different from any other conventional firewall?
Know about the different kinds of firewalls available
There are 4 types of firewall exists in networking. Those are namely network level, circuit level, application level and stateful multilayer.
Firewalls generally categorized by their working level in network. Network level firewall works at the network level. It inspects the header of packet and the checks the information of sender and receiver computer. Circuit level firewall works on session layer of OSI model. It validates a session that is requested by two packets. This firewall have the capability to hide the network from outside world. Application level firewall which is called as proxies also, works same like circuit level but it works on specific web based applications. It protects application from malicious attacks, spams, viruses, this firewall is able to block websites also in browser depending on website content. Stateful multilayer has the capability of all those three mentioned firewall and it provides direct connection between a host and a client. This firewall do not use proxies and works faster than other firewalls.
Virtual firewall is a network firewall service or we can say it as network firewall appliance. It runs within a fully virtualized network. The functioning is same as network firewall like checking packet header.
Virtual firewall can operate on different modes which depends on point of deployment of virtual firewall. Now this two modes are Bridge mode and supervisor mode.
In bridge mode virtual firewall is inside virtual network and sits as an inter-network virtual bridge. But in supervisor mode virtual firewall is not a part of virtual network and it resides in virtual machine monitor.
Personal firewall is an application that operates and installed on a particular computer and control network traffic to and from that particular computer. It control access or deny of incoming and outgoing communications based on security policy that has already configured as set up.
The usability of personal firewall differentiates it with other conventional firewall. Personal firewall operates on a specific computer where it is installed whereas conventional firewalls are installed on a designated interface between two or more networks. Hence the work area of conventional firewalls are very broad and vast also with respect to personal firewall. Conventional firewall controls and works on policy that defined over one or more network whereas personal firewall works on policy defined on a specific computer.