Transparent auto-negotiation of ethernet

Abstract

A system for negotiating Ethernet link settings between interconnected nodes in a network having an Ethernet protocol stack that includes a PCS sub-layer with an auto-negotiation function. The system comprises connecting an intermediate device coupled between two network nodes via optical or copper interfaces, with the link settings between each node and the connected intermediate device being the same, thereby bypassing the auto-negotiation of the PCS sub-layer in the intermediate device. The intermediate device may transparently send negotiation messages from each node to the other during the link negotiation phase without interacting with those messages. Instead of the intermediate device, a single form pluggable (SFP) device may be connected between the two network nodes via optical or copper interfaces on the network side and via an SFP slot on the device side.

1 . A method of negotiating Ethernet link settings between interconnected nodes in a network, said interconnected nodes having an Ethernet protocol stack that includes a PCS sub-layer with an auto-negotiation function, comprising:
 coupling an intermediate device between two network nodes via optical or copper interfaces; and   negotiating the link settings identically between each node and the connected intermediate device by bypassing said auto-negotiation function of the PCS sub-layer in the said intermediate device.   
     
     
         2 . The method of  claim 1 , wherein the intermediate device transparently sends negotiation messages from each node to the other during the link negotiation phase without interacting with said messages 
     
     
         3 . The method of  claim 1 , wherein a pair of network devices are attached to said intermediate device, and said intermediate device includes two physical ports and a management module that sets the two physical ports to Ethernet settings negotiated between said pair of network devices. 
     
     
         4 . The method of  claim 1 , which includes resuming normal Ethernet functioning after said negotiating of the link settings is complete. 
     
     
         5 . The method of  claim 1  in which said Ethernet protocol stack includes a PMA sub-layer providing an interface with said PCS sub-layer, said PCS sub-layer includes a receive function and a transmit function, and in which said auto-negotiation function of said PCS sub-layer is replaced with a programmable switching function for the interface provided by said PMA sub-layer with said PCS sub-layer. 
     
     
         6 . The method of  claim 5  which includes a management module, and in which said programmable switching function is effected by said management module. 
     
     
         7 . The method of  claim 5  in which said Ethernet protocol stack includes a MAC sub-layer interfacing directly with said transmit and receive functions of said PCS layer, and said PCS receive function forwards (a) first selected Ethernet ordered sets to a switch function, and (b) second Ethernet ordered sets to said MAC sub-layer. 
     
     
         8 . The method of  claim 5  in which said Ethernet protocol stack includes a MAC sub-layer interfacing directly with said management module, and said management module provides a programmable switching function for the interface between said MAC sub-layer and said receive and transmit functions of said PCS sub-layer. 
     
     
         9 . A method of negotiating Ethernet link settings between interconnected nodes in a network, comprising:
 connecting a single form pluggable (SFP) device between two network nodes via optical or copper interfaces on the network side and via an SFP slot on the device side; and   negotiating the link settings identically between each node and the connected SFP device.   
     
     
         10 . The method of  claim 5 , wherein the SFP device transparently sends negotiation messages from each node to the other during the link negotiation phase without interacting with said messages. 
     
     
         11 . The method of  claim 5 , wherein said SFP device includes two physical ports, and which includes a pair of network devices attached to said SFP device, and a management module that sets said two physical ports to Ethernet settings negotiated between said pair of network devices. 
     
     
         12 . The method of  claim 7 , wherein the SFP ports resume normal Ethernet functioning after a link negotiation sequence is complete 
     
     
         13 . A system for negotiating Ethernet link settings between interconnected nodes in a network, said interconnected nodes having an Ethernet protocol stack that includes a PCS sub-layer with an auto-negotiation function, comprising:
 an intermediate device coupled between two network nodes via optical or copper interfaces; and   the link settings between each node and the connected intermediate device being the same, thereby bypassing said auto-negotiation function of the PCS sub-layer in the said intermediate device.   
     
     
         14 . The system of  claim 13 , wherein the intermediate device transparently sends negotiation messages from each node to the other during a link negotiation phase without interacting with said messages 
     
     
         15 . The system of  claim 13 , wherein a pair of network devices are attached to said intermediate device, and said intermediate device includes two physical ports and a management module that sets the two physical ports to Ethernet settings negotiated between said pair of network devices. 
     
     
         16 . The system of  claim 13  in which said Ethernet protocol stack includes a PMA sub-layer providing an interface with said PCS sub-layer, said PCS sub-layer includes a receive function and a transmit function, and in which said auto-negotiation function of said PCS sub-layer is replaced with a programmable switching function for the interface provided by said PMA sub-layer with said PCS sub-layer. 
     
     
         17 . The system of  claim 16  which includes a management module, and in which said programmable switching function is effected by said management module. 
     
     
         18 . The system of  claim 16  in which said Ethernet protocol stack includes a MAC sub-layer interfacing directly with said transmit and receive functions of said PCS layer, and said PCS receive function forwards (a) first selected Ethernet ordered sets to a switch function, and (b) second Ethernet ordered sets to said MAC sub-layer. 
     
     
         19 . The system of  claim 16  in which said Ethernet protocol stack includes a MAC sub-layer interfacing directly with said management module, and said management module provides a programmable switching function for the interface between said MAC sub-layer and said receive and transmit functions of said PCS sub-layer. 
     
     
         20 . A system for negotiating Ethernet link settings between interconnected nodes in a network, comprising:
 a single form pluggable (SFP) device coupled, between two network nodes via optical or copper interfaces on the network side and via an SFP slot on the device side,   
     
     
         21 . The system of  claim 20 , wherein the SFP device transparently sends negotiation messages from each node to the other during the link negotiation phase without interacting with said messages. 
     
     
         22 . The system of  claim 20 , wherein said SFP device includes at least one physical port and a second logical port over an SFP connector, and which includes a pair of network devices attached to said SFP device, and a management module that sets said network devices ports to Ethernet settings negotiated between said pair of network devices. 
     
     
         23 . The system of  claim 22 , wherein the SFP ports resume normal Ethernet functioning after a link negotiation sequence is complete