What are Firewalls?
In construction, a firewall is a non-flammable wall that prevents fires from spreading throughout a building. Homes, for example, may have a firewall between the garage and the rest of the house to prevent garage fires from threatening other rooms. With the rapid popularization of the internet, the term firewall is more commonly used in computer networking. Like the firewalls used in homes and buildings, computer firewalls act as a barrier between computers on a network. For companies with a computer network or for individuals with a permanent connection to the internet (such as through DSL or cable), a firewall is critical. Without a firewall, intruders on the network would likely be able to destroy, tamper with or gain access to the files on your computer. Firewalls can come in the form of hardware or software. Without getting into the complex details of how firewalls work, suffice it to say that function with a set of filters that are constantly monitoring traffic on the network. Wh
A firewall is a system designed to prevent unauthorized access to or from a private network. Firewalls can be implemented in both hardware and software, or a combination of both. Firewalls are frequently used to prevent unauthorized Internet users from accessing private networks connected to the Internet, especially intranets. All messages entering or leaving the intranet pass through the firewall, which examines each message and blocks those that do not meet the specified security criteria. Firewall Techniques: Packet filter: Looks at each packet entering or leaving the network and accepts or rejects it based on user-defined rules. Packet filtering is fairly effective and transparent to users, but it is difficult to configure. In addition, it is susceptible to IP spoofing. Application gateway: Applies security mechanisms to specific applications, such as FTP and Telnet servers. This is very effective, but can impose a performance degradation. Circuit-level gateway: Applies security me
