Forwarding Plane Data Communications Channel for Ethernet Transport Networks

Abstract

Described is a process and system for providing an extensible forwarding plane data communications channel adapted to selectively support operations, administration and maintenance (OAM) activity within one or more different domains of an Ethernet transport network. The data communication channel is established using Ethernet protocol data units forwarded within the forwarding plane, between network elements. The Ethernet protocol data units can be Ethernet OAM frames modified to include an OpCode indicative of a maintenance communication channel. The OAM frames are generated at a selected one of the network elements (source), forwarded along the same network path as the Ethernet frames, and terminate at another network element (destination) associated with a maintenance level identified within the OAM frame. The source and destination network elements can reside on a domain boundary using the Ethernet OAM frames flowing therebetween to relay maintenance communications channel messages.

1 .- 25 . (canceled) 
     
     
         26 . A method of operating a network element for use in a communications network supporting transmission of Ethernet protocol data units, the method comprising:
 providing at least one maintenance entity level identifier, each maintenance entity level identifier being associated with at least one termination maintenance entity; and   generating at least one Ethernet protocol data unit, the at least one Ethernet protocol data unit comprising:
 content signifying that the Ethernet protocol data unit comprises content related to OAM; and 
 at least one maintenance entity level identifier. 
   
     
     
         27 . A method as defined in  claim 26 , further comprising forwarding the at least one Ethernet protocol data unit along a forwarding plane of the data communications network. 
     
     
         28 . A method as defined in  claim 27 , further comprising:
 receiving Ethernet protocol data units from the data communications network;   identifying at least one received Ethernet protocol data unit comprising content signifying that the Ethernet protocol data unit comprises content related to OAM and content identifying a maintenance entity level associated with at least one maintenance termination entity that is to process the received Ethernet protocol data unit; and   forwarding the at least one identified Ethernet protocol data unit to an OAM application when the network element has a maintenance entity level corresponding to the maintenance entity level identified in the received Ethernet protocol data unit.   
     
     
         29 . A method as defined in  claim 28 , further comprising:
 generating at least one reply Ethernet protocol data unit in response to the identified Ethernet protocol data unit, the reply Ethernet protocol data unit comprising:   content signifying that the Ethernet protocol data unit comprises content related to OAM; and   content identifying the maintenance entity level identified in the identified Ethernet protocol data unit.   
     
     
         30 . A method as defined in  claim 26 , wherein the Ethernet protocol data unit generator is operable to generate at least one Ethernet Operation, Administration and Maintenance (OAM) frame. 
     
     
         31 . A method as defined in  claim 30 , wherein the step of generating the at least one Ethernet protocol data unit comprises generating the Ethernet protocol data unit to further comprise content identifying a functionality of the Ethernet data protocol unit. 
     
     
         32 . A method as defined in  claim 31 , wherein the step of generating the at least one Ethernet protocol data unit comprises generating the at least one Ethernet protocol unit with the content identifying a functionality of the Ethernet data protocol unit identifying orderwire functionality. 
     
     
         33 . A method as defined in  claim 31 , wherein the step of generating the at least one Ethernet protocol data unit comprises generating the at least one Ethernet protocol unit with the content signifying that the Ethernet protocol data unit within a general portion of the Ethernet protocol data unit and the content identifying the functionality within an application-specific portion of the Ethernet protocol data unit. 
     
     
         34 . A network element for use in a communications network supporting transmission of Ethernet protocol data units, the network element comprising:
 a data store operable to store at least one maintenance entity level identifier, each maintenance entity level identifier being associated with at least one termination maintenance entity; and   an Ethernet protocol data unit generator operable to generate at least one Ethernet protocol data unit, the at least one Ethernet protocol data unit comprising:   content signifying that the Ethernet protocol data unit comprises content related to OAM; and   at least one maintenance entity level identifier.   
     
     
         35 . A network element as defined in  claim 34 , further comprising an Ethernet protocol data unit forwarder operable to forward the at least one Ethernet protocol data unit along a forwarding plane of the communications network. 
     
     
         36 . A network element as defined in  claim 35 , further comprising:
 an Ethernet procotol data unit receiver operable to receive Ethernet protocol data units from the communications network;   at least one Ethernet protocol data unit processor operable to identify at least one received Ethernet protocol data unit comprising content signifying that the Ethernet protocol data unit comprises content related to OAM and content identifying a maintenance entity level associated with at least one maintenance termination entity that is to process the received Ethernet protocol data unit; and   a channel agent operable to forward the at least one identified Ethernet protocol data unit to an OAM application when the network element has a maintenance entity level corresponding to the maintenance entity level identified in the received Ethernet protocol data unit.   
     
     
         37 . A network element as defined in  claim 36 , wherein the Ethernet protocol data unit generator is operable to generate at least one reply Ethernet protocol data unit in response to the identified Ethernet protocol data unit, the reply Ethernet protocol data unit comprising:
 content signifying that the Ethernet protocol data unit comprises content related to OAM; and   content identifying the maintenance entity level identified in the identified Ethernet protocol data unit.   
     
     
         38 . A network element as defined in  claim 34 , wherein the Ethernet protocol data unit generator is operable to generate at least one Ethernet Operation, Administration and Maintenance (OAM) frame. 
     
     
         39 . A network element as defined in  claim 38 , wherein the Ethernet protocol data unit generator is operable to generate the at least one Ethernet protocol unit to further comprise content identifying a functionality of the Ethernet data protocol unit. 
     
     
         40 . A network element as defined in  claim 39 , wherein the Ethernet protocol data unit generator is operable to generate the at least one Ethernet protocol unit with the content identifying a functionality of the Ethernet data protocol unit identifying orderwire functionality 
     
     
         41 . A network element as defined in  claim 39 , wherein the Ethernet protocol data unit generator is operable to generate the at least one Ethernet protocol unit with the content signifying that the Ethernet protocol data unit within a general portion of the Ethernet protocol data unit and the content identifying the functionality within an application-specific portion of the Ethernet protocol data unit. 
     
     
         42 . A system for providing a data communications channel between at least two network elements configured to support transmission of Ethernet protocol data units over a communications network, the system comprising:
 a first network element comprising:
 an Ethernet protocol data unit generator operable to generate at least one Ethernet protocol data unit, the at least one Ethernet protocol data unit comprising:
 content signifying that the Ethernet protocol data unit comprises content related to OAM; and 
 content identifying a maintenance entity level associated with at least one termination maintenance entity that is to process the generated Ethernet protocol data unit; and 
 
 an Ethernet protocol data unit forwarder operable to forward the at least one Ethernet protocol data unit along a forwarding plane of the communications network; and 
   a second network element comprising:
 an Ethernet procotol data unit receiver operable to receive Ethernet protocol data units from the communications network; 
 at least one Ethernet protocol data unit processor operable to identify at least one received Ethernet protocol data unit comprising content signifying that the Ethernet protocol data unit comprises content related to OAM and content identifying a maintenance entity level associated with at least one maintenance termination entity that is to process the received Ethernet protocol data unit; and 
 a channel agent operable to forward the at least one identified Ethernet protocol data unit to an OAM application when the network element has a maintenance entity level corresponding to the maintenance entity level identified in the received Ethernet protocol data unit. 
   
     
     
         43 . A system as defined in  claim 42 , wherein the second network element further comprises:
 an Ethernet protocol data unit generator operable to generate at least one reply Ethernet protocol data unit in response to the identified Ethernet protocol data unit, the reply Ethernet protocol data unit comprising:
 content signifying that the Ethernet protocol data unit comprises content related to OAM; and 
 content identifying the maintenance entity level identified in the identified Ethernet protocol data unit. 
   
     
     
         44 . A method of providing a data communications channel between at least two network elements configured to support transmission of Ethernet protocol data units over a communications network, the method comprising:
 at a first network element:
 generating at least one Ethernet protocol data unit, the at least one Ethernet protocol data unit comprising:
 content signifying that the Ethernet protocol data unit comprises content related to OAM; and 
 content identifying a maintenance entity level associated with at least one termination maintenance entity that is to process the generated Ethernet protocol data unit; and 
 
 forwarding the at least one Ethernet protocol data unit along a forwarding plane of the communications network; and 
   at a second network element:
 receiving Ethernet protocol data units from the communications network; 
 identifying at least one received Ethernet protocol data unit comprising content signifying that the Ethernet protocol data unit comprises content related to OAM and content identifying a maintenance entity level associated with at least one maintenance termination entity that is to process the received Ethernet protocol data unit; and 
 forwarding the at least one identified Ethernet protocol data unit to an OAM application when the network element has a maintenance entity level corresponding to the maintenance entity level identified in the received Ethernet protocol data unit. 
   
     
     
         45 . A method as defined in  claim 44 , further comprising:
 at the second network element, generating at least one reply Ethernet protocol data unit in response to the identified Ethernet protocol data unit, the reply Ethernet protocol data unit comprising:
 content signifying that the Ethernet protocol data unit comprises content related to OAM; and 
 content identifying the maintenance entity level identified in the identified Ethernet protocol data unit.