The All-New Switch Book: The Complete Guide to LAN Switching Technology, Second Edition

6.2. Eine Kleine Sourceroutinggeschichte

Source Routing was developed by IBM as part of its overall design of the Token Ring LAN architecture^[] [IBM87]. For the first 10 years of its life (1985–1995) virtually all Token Ring installations used source routing bridges exclusively. Transparent bridges were rarely used on Token Ring networks; few vendors even provided such products. Because of the differences in behavior between source routed and transparently bridged catenets, users that needed to support both Token Ring and Ethernet LANs within their organizations had to carefully partition network resources such that any traffic traversing between the two worlds passed through devices specifically designed to deal with the complexities of source routing-to-transparent bridge interconnection (see section 6.6).

^[] While most network equipment manufacturers offered Token Ring products, IBM was the only computer systems manufacturer that endorsed Token Ring (and source routing) as its LAN strategy. In contrast, numerous computer systems manufacturers endorsed Ethernet and transparent bridging, including Digital Equipment Corp., Sun Microsystems, Hewlett-Packard, Apple Computer, and many others. Thus, Token Ring LANs and source routing bridges were deployed primarily within IBM's customer base, particularly those customers who used IBM mainframes and mid-range computers.

For many years, Token Ring was the only LAN technology supported on these systems, virtually creating its own market ...