Describe the purpose of a intrusion detection system, intrusion prevention system, and intrusion detection and prevention system. . Assess the effectiveness of these devices in protecting the perimeter of the network. Include an explanation of what they do protect and what they do not protect resources and assets in todays technology age. Firewalls provide security by blocking and monitoring the transmitted electronic communications. There are four common firewalls such as: Filtering- 1. Packet In packet filtering software examines the header portion of the packet and determines whether it will be allowed or denied access to the port it is attempting to gain access to.
If the packet is denied it is dropped and the information is never ransmitted to the end user. If the packet is accepted the packet goes through and the end user receives it. Packet filtering is a relatively inexpensive way to protect your PC by using a firewall. Linux has packet filtering built into the system itself which takes out some of the expenses when installing a firewall and intrusion detection system. 2. Circuit Level Gateway- In circuit level gateway the security is at the transport layer. This type of firewall is implemented and governed by using the SOCKS protocol. SOCKS was designed by David Koblas .
It is a protocol that relays TCP sessions to a firewall host to allow application users transparent access throughout the firewall. It is separate from application protocols and can be used for several different services such as: Telnet- A protocol that allows a user to access a computer remotely using TCP/IP networks. Ftp- A protocol that is an industry standard for file transferring. This is one of the most widely used protocols to transfer files. One of the most common examples is downloading a file from the internet such as a picture, video, etc. 3. Application Level Gateway 4. Stateful Multilayer Inspection