Firewall Technology

Firewall Technology



Firewall - a system or combination of systems, allowing dividing the network into two or more parts and implementing a set of rules that define conditions for the packets from one part to another. Typically, this boundary is drawn between the local enterprise network and INTERNET, although it can be carried out within the local network. Firewall thus passes through itself all the traffic. For each transmitted packet firewall decides to ignore it or drop it. In order for the firewall could make these decisions, it is necessary to define a set of rules.

In every organization there is (or should be) a Security Policy, a document that expresses what is allowed regarding, for example, the management of information. Corporate networks are not bounded by physical limits, in place security policies exist. Currently networking technologies (and especially the Internet) allows connectivity to anyone, anywhere, belongs to an internal network or external, at any time. To accommodate this security policy should be implemented throughout the organization, providing comprehensive coverage and policy-based management in all offices, remote and mobile users, business partners and customers. To be effective these policies must include a broad range of services that govern access to information resources on the network, protect the privacy and integrity of information and communications.Firewalls can be classified according to their evolution. The first generation of firewalls was routers selection filtering data packets, listening to them and rejecting those that did not meet pre-programmed format. Security was provided by analyzing the source address, port number, the IP flag or any other home network feature in each packet by comparing them with the appropriate access to the network. The packet filtering is an essential part of a firewall, but insufficient by itself (Peter, 2005).

Custom solutions are another type of implement a firewall. These solutions require professionals with expertise in communications protocols, operating systems and connectivity, full-time to build a solution that interoperates with the existing network of the organization. Are safer than the screening routers but involve high costs and are available only for large organizations. To reduce these costs appeared on the market some firewalls "toolkits" under the philosophy "do it yourself" as needed. 

Firewalls, secure operating systems provide a reliable level of security available at low cost by various levels of users. As high-level firewall provides security when in the operating system itself, Manufacturers achieve this by licensing the source code for firewall so that the kernel of an operating system on which you will deploy. Services and eliminating insurance subsystems become the 'holes' in security. This firewall uses three types of filtering: packet, application level gateways and circuit-level gateways, to create the most robust security solution possible. An important point is its ease of use and no additional programming required for installation.  Mention some products firewalls: Checkpoint Firewall-l, Borderware Firewall Server 4.1, Secure Computing, and IBM Firewall 3.1 of IBM. 

It is a filter that controls the passage of information from one network to another. A firewall acts as a doorman in a building, checks who goes, who comes out and more importantly it brings (Hong, ...