The Cambridge Ring was an experimental local area network architecture developed at the Computer Laboratory, University of Cambridge starting in 1974 and continuing into the 1980s. It was a ring network with a theoretical limit of 255 nodes (though such a large number would have badly affected performance), around which cycled a fixed number of packets. Free packets would be "loaded" with data by a sending machine, marked as received by the destination machine, and "unloaded" on return to the sender; thus in principle, there could be as many simultaneous senders as packets. The network ran over twin twisted-pair cabling (plus a fibre-optic section).
There are strong similarities between the Cambridge Ring and an earlier ring network developed at Bell Labs based on a design by John R. Pierce. That network used T1 lines at bit rate of 1.544 MHz and accommodating 522 bit messages (data plus address).
- Cambridge Distributed Computing System
- Internet in the United Kingdom § History
- NPL network
- Packet switching
- Token Ring
- University of London Computer Centre
- "A brief informal history of the Computer Laboratory". University of Cambridge. 20 December 2001. Archived from the original on 13 November 2010.
- John R. Pierce, Network for Block Switching of Data, Bell System Technical Journal, Vol. 51, No. 6 (July-August, 1972); pages 1133-1145.
- W. J. Kropfl, An Experimental Data Block Switching System, Bell System Technical Journal, Vol. 51, No. 6 (July-August, 1972); pages 1147-1165.
- C. H. Coker, An Experimental Interconnection of Computers Through a Loop, Bell System Technical Journal, Vol. 51, No. 6 (July-August, 1972); pages 1167-1175.
- Andrew Hopper; Roger Needham. "The Cambridge Fast Ring Networking System" (PDF). ORL-88-1.
- Cambridge Ring Hardware
- Cambridge Fast Ring
- Cambridge Backbone Ring Hardware
- Cambridge Computer Lab Ring
- "Ring PCB". Relic Archive. University of Cambridge Computer Laboratory. Retrieved 9 April 2011.