Internetworking
From Free net encyclopedia
Internetworking involves connecting two or more distinct computer networks together into an internetwork (often shortened to internet), using devices called routers to connect them together, to allow traffic to flow back and forth between them. (Routers were originally called gateways, but that term was discarded in this context, due to confusion with functionally different devices using the same name.) The routers guide traffic on the correct path (among several different ones usually available) across the complete internetwork to their destination.
(Some people inaccurately refer to the connecting together of networks with bridges as internetworking, but the resulting system mimics a single subnetwork, and no internetworking protocol (such as IP) is required to traverse it.)
Internetworking started as a way to connect disparate types of networking technology, but it became widespread through the developing need to connect two or more local area networks via some sort of wide area network. The definition now includes the connection of other types of computer networks such as personal area networks.
The most notable example of internetworking in practice is the Internet, a network of networks running different low-level protocols, unified by an internetworking protocol, the Internet Protocol (IP).
IP only provides an unreliable packet service across an internet. To transfer data reliably, applications must utilize a Transport layer protocol, such as TCP, which provides a reliable stream (These terms do not mean that IP is actually unreliable but instead that it sends packets without contacting and establishing a connection with the destination router beforehand. The opposite applies for reliable). Since TCP is the most widely used transport protocol, people commonly refer to TCP and IP together, as "TCP/IP". Some applications occasionally use a simpler transport protocol (called UDP) for tasks which do not require absolutely reliable delivery of data, such as video streaming.
See also
External links
- E-book (pdf format) - Deals with the foundations of major internetworking architectures (chapters 4 to 9).de:Internetworking