loopback Last modified: Friday, March 24, 2006
(1) In telecommunications, loopback is a method used to perform transmission tests of the lines at the switching center. (2) Loopback is a communication channel with only one endpoint. TCP/IP networks specify a loopback that allows client software to communicate with server software on the same computer. users can specify an IP address, usually 127.0.0.1, which will point back to the computer's TCP/IP network configuration. The range of addresses for loopback functionality is the range of 127.0.0.0 to 127.255.255.255. Similar to ping, loopback enables a user to test one's own network to ensure the IP stack is functioning properly.
•E-mail this definition to a colleague• For internet.com pages about loopback . Also check out the following links! PracticallyNetworked.com  PracticallyNetworked.com provides easy-to-understand help for small-network builders. The site contains how-to information for setting up and debugging home-office and small-business networks. Users can also find extensive troubleshooting information, tips on getting applications to work through firewalls, product reviews on network hardware and software, and more. PracticallyNetworked.com Discussion Forums  If network connections, sharing computers, router problems or other networking issues are bogging you down, then the PracticallyNetworked.com discussion forum is the place to be. Here you'll find help and support for all your network-related problems. Internet Protocol Tutorial Loopback is a test mechanism of network adapters. Messages sent to 127.0.0.1 do not get delivered to the network. Instead, the adapter intercepts all loopback messages and returns them to the sending application. IP applications often use this feature to test the behavior of their network interface. The TCP/IP Guide - Loopback Addresses Normally, when a TCP/IP application wants to send information, that information travels down the protocol layers to IP where it is encapsulated in an IP datagram. That datagram then passes down to the data link layer of the device's physical network for transmission to the next hop, on the way to the IP destination.	Internet Protocols Networks Telecommunications IP address ping protocol protocol stack TCP TCP/IP Give Us Your Feedback Network Cables loopback Products Shop by Top Models: Cisco SC Loopback: Multimode 50-Micron Fiber Optic Test Cable (SC-LOOPBACK-50-MM) 1 store offers from $8 - $8 Cisco FC Loopback: Multimode 50-Micron Fiber Optic Test Cable (FC-LOOPBACK-50-MM) 1 store offers from $8 - $8 Cisco LC Loopback: Multimode 50-Micron Fiber Optic Test Cable (LC-LOOPBACK-50-MM) 1 store offers from $9.5 - $9.5 Cisco FC Loopback: Multimode 62.5-Micron Fiber Optic Test Cable (FC-LOOPBACK-62.5-MM) 1 store offers from $8.5 - $8.5 Cisco SC Loopback: Single-Mode 9.0-Micron Fiber Optic Test Cable (SC-LOOPBACK-9-SM) 1 store offers from $11 - $11