Intel Corporation
Method of ethernet auto-negotiation over one cable

Abstract:

Examples include a method of identifying single twisted pair cable Ethernet auto-negotiation requests or double twisted pair cables Ethernet auto-negotiation requests using detection of message time interval patterns. The method includes receiving, by a first Ethernet device, a plurality of messages transmitted by a second Ethernet device over a single twisted pair cable connecting the first Ethernet device and the second Ethernet device; storing one or more time intervals between starting times of successive pairs of the plurality of messages; determining if a pattern is found in the time intervals; when the pattern is found, setting a single twisted pair cable communications mode between the first Ethernet device and the second Ethernet device; and performing priority resolution between the first Ethernet device and the second Ethernet device.