Patent ID: 8493843

Claim:
An autonegotiation method that enables an identification of a new communication operating mode over an Ethernet link having four wire pairs, comprising: detecting a failure of communication in one of the four wire pairs in the Ethernet link, while operating in a first communication operating mode having a first link rate; upon said detection, running an autonegotiation process that identifies a second communication operating mode over the Ethernet link, said autonegotiation process identifying said second communication operating mode through an examination of a set of a plurality of possible communication operating modes in a pre-defined sequential order, at least two of said plurality of possible communication operating modes having the same link rate but using two different sets of wire pairs, wherein said pre-defined sequential order includes a sequential transition from a lower link rate to a higher link rate; and changing a speed of communication on the Ethernet link from said first link rate to a second link rate, said second link rate being lower than said first link rate, wherein the communication on the Ethernet link at said second link rate uses only two wire pairs.