# US 2010/0165995 A1 · Routing frames in a computer network using bridge identifiers > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2010/0165995 A1 - Document ID: US20100165995A1 - Status: Published application - Kind: A1 - Application number: 12/344,644 - Filed: 2008-12-29 - Published: 2010-07-01 - Earliest claimed: 2008-12-29 - Assignees: Juniper Networks, Inc. - Inventors: Apurva Mehta; Ramasamy Ramanathan; Kumar Mehta; Ramanarayanan Ramakrishnan - Web page: https://patentgrep.com/patent/US20100165995A1 ## CPC - H04L 45/12: Shortest path evaluation - H04L 12/462: {LAN interconnection over a bridge based backbone} - H04L 45/04: {Interdomain routing, e.g. hierarchical routing} - H04L 45/66: {Layer 2 routing, e.g. in Ethernet based MAN's} - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) ## Abstract Methods, apparatus, and products for routing frames in a network using bridge identifiers, wherein the network includes a plurality of bridge nodes. At least one of the bridge nodes operates as an ingress bridge node through which frames are received into the network. At least one of the bridge nodes operates as an egress bridge node through which frames are transmitted out of the network. One of the bridge nodes receives, from the ingress bridge node, a frame for transmission to a destination node. The destination node connects to the network through the egress bridge node. The frame includes an ingress bridge identifier and an egress bridge identifier. The bridge that received the frame then routes the frame to the egress bridge node through which the destination node connects to the network in dependence upon the ingress bridge identifier and the egress bridge identifier included in the frame. ## Claims ### Claim 1 A method of routing frames in a computer network using bridge identifiers, the computer network including a plurality of bridge nodes, at least one of the plurality of bridge nodes operating as an ingress bridge node through which the frames are received into the computer network, and at least one of the plurality of bridge nodes operating as an egress bridge node through which the frames are transmitted out of the computer network, the method comprising the steps of: receiving, by one of the plurality of bridge nodes from the ingress bridge node, a frame for transmission to a destination node, the destination node connected to the network through the egress bridge node, the frame including an ingress bridge identifier and an egress bridge identifier; and routing, by the bridge node to the egress bridge node through which the destination node connects to the network, the frame in dependence upon the ingress bridge identifier and the egress bridge identifier included in the frame. ### Claim 2 (depends on 1) The method of claim 1 wherein the frame further comprises a vender header specified by a vender of the ingress bridge node, the vender header including the ingress bridge identifier and the egress bridge identifier. ### Claim 3 (depends on 1) The method of claim 1 wherein the step of routing the frame further comprises the steps of: adding, to the frame in dependence upon the ingress bridge identifier and the egress bridge identifier, a shortest path bridging header conforming to a shortest path bridging protocol, the shortest path bridging header including an ingress bridge nickname and an egress bridge nickname, the ingress bridge nickname allocated to the ingress bridge node according to a predetermined protocol, the egress bridge nickname allocated to the egress bridge node according to the predetermined protocol; and routing the frame to the egress bridge node in dependence upon the ingress bridge nickname and the egress bridge nickname. ### Claim 4 (depends on 3) The method of claim 3 wherein the step of routing the frame to the egress bridge node in dependence upon the ingress bridge nickname and the egress bridge nickname further comprises the steps of: identifying, in dependence upon the egress bridge nickname, a media access control (‘MAC’) address for a next bridge in the network that is on a path from the bridge node to the egress bridge node; adding the MAC address for the next bridge node to the frame; and routing the frame to the next bridge node in dependence upon the MAC address. ### Claim 5 (depends on 3) The method of claim 3 wherein the bridge node supports a Transparent Interconnection of Lots of Links (‘TRILL’) protocol and the shortest path bridging header conforms to the TRILL protocol. ### Claim 6 (depends on 1) The method of claim 1 wherein the step of routing the frame further comprises the steps of: determining, in dependence upon the egress bridge identifier, a next bridge in the network that is on a path from the bridge node to the egress bridge node; and routing the frame to the next bridge node. ### Claim 7 (depends on 1) The method of claim 1 wherein the bridge node is the egress bridge node. ### Claim 8 (depends on 1) The method of claim 1 wherein the ingress bridge node adds the ingress bridge identifier and the egress bridge identifier to the frame. ### Claim 9 (depends on 1) The method of claim 1 wherein hardware of the ingress bridge node and hardware of the egress bridge node are incapable of supporting mac-in-mac encapsulation. ### Claim 10 A method of routing frames in a computer network using bridge identifiers, the computer network including a plurality of bridge nodes, at least one of the plurality of bridge nodes operating as an ingress bridge node through which the frames are received into the computer network, and at least one of the plurality of bridge nodes operating as an egress bridge node through which the frames are transmitted out of the computer network, the method comprising the steps of: receiving, by the ingress bridge node from a source node through another computer network, a frame, the frame specifying a source node address for the source node originating the frame, the frame specifying a destination node address for a destination node to which the frame is transmitted; retrieving, by the ingress bridge node, an ingress bridge identifier for the ingress bridge node; identifying, by the ingress bridge node, an egress bridge identifier for the egress bridge node in dependence upon the destination node address specified by the frame; adding, by the ingress bridge node, the ingress bridge identifier and the egress bridge identifier to the frame; and routing, by the ingress bridge node, the frame through the computer network to the egress bridge node through which the destination node connects to the network. ### Claim 11 (depends on 10) The method of claim 10 wherein hardware of the ingress bridge node and hardware of the egress bridge node are incapable of supporting mac-in-mac encapsulation. ### Claim 12 A method of routing frames in a computer network using bridge identifiers, the computer network including a plurality of bridge nodes, at least one of the plurality of bridge nodes operating as an ingress bridge node through which the frames are received into the computer network, and at least one of the plurality of bridge nodes operating as an egress bridge node through which the frames are transmitted out of the computer network, the method comprising the steps of: receiving, by one of the plurality of bridge nodes connected to the egress bridge node by a single hop, a frame for transmission to a destination node, the destination node connected to the network through the egress bridge node, and the frame having a shortest path bridging header that includes an ingress bridge nickname and an egress bridge nickname; determining, by the bridge node, that the frame traverses the egress bridge node on the next network hop; replacing, by the bridge node in response to the determination, the shortest path bridging header with an ingress bridge identifier and an egress bridge identifier; and routing, by the bridge node, the frame to the egress bridge node. ### Claim 13 (depends on 12) The method of claim 12 wherein the step of replacing, by the bridge node in response to the determination, the shortest path bridging header with an ingress bridge identifier and an egress bridge identifier further comprises the step of adding a vender header to the frame that includes the ingress bridge identifier and the egress bridge identifier. ### Claim 14 (depends on 12) The method of claim 12 wherein the bridge node supports a Transparent Interconnection of Lots of Links (‘TRILL’) protocol and the shortest path bridging header conforms to the TRILL protocol. ### Claim 15 (depends on 12) The method of claim 12 wherein hardware of the ingress bridge node and hardware of the egress bridge node are incapable of supporting mac-in-mac encapsulation. ### Claim 16 A method of routing frames in a computer network using bridge identifiers, the computer network including a plurality of bridge nodes, at least one of the plurality of bridge nodes operating as an ingress bridge node through which the frames are received into the computer network, and at least one of the plurality of bridge nodes operating as an egress bridge node through which the frames are transmitted out of the computer network, the method comprising the steps of: receiving, by the egress bridge node from one of the plurality of bridge nodes, a frame for transmission to a destination node, the destination node connected to the network through the egress bridge node, and the frame including an ingress bridge identifier and an egress bridge identifier; removing, by the egress bridge node, the ingress bridge identifier and the egress bridge identifier from the frame; and routing, by the egress bridge node, the frame for delivery to the destination node. ### Claim 17 (depends on 16) The method of claim 16 wherein hardware of the ingress bridge node and hardware of the egress bridge node are incapable of supporting mac-in-mac encapsulation. ### Claim 18 An apparatus for routing frames in a computer network using bridge identifiers, the computer network including a plurality of bridge nodes, at least one of the plurality of bridge nodes operating as an ingress bridge node through which the frames are received into the computer network, and at least one of the plurality of bridge nodes operating as an egress bridge node through which the frames are transmitted out of the computer network, the apparatus comprising: a computer memory storing a computer program, the computer program comprising instructions that: receive, by one of the plurality of bridge nodes from the ingress bridge node, a frame for transmission to a destination node, the destination node connected to the network through the egress bridge node, the frame including an ingress bridge identifier and an egress bridge identifier, and route, by the bridge node to the egress bridge node through which the destination node connects to the network, the frame in dependence upon the ingress bridge identifier and the egress bridge identifier included in the frame; and a processor that executes the instructions. ### Claim 19 (depends on 18) The apparatus of claim 18 wherein the frame further comprises a vender header specified by a vender of the ingress bridge node, the vender header including the ingress bridge identifier and the egress bridge identifier. ### Claim 20 (depends on 18) The apparatus of claim 18 wherein the instructions that route the frame further comprise instructions that: add, to the frame in dependence upon the ingress bridge identifier and the egress bridge identifier, a shortest path bridging header conforming to a shortest path bridging protocol, the shortest path bridging header including an ingress bridge nickname and an egress bridge nickname, the ingress bridge nickname allocated to the ingress bridge node according to a predetermined protocol, the egress bridge nickname allocated to the egress bridge node according to the predetermined protocol; and route the frame to the egress bridge node in dependence upon the ingress bridge nickname and the egress bridge nickname. ### Claim 21 (depends on 18) The apparatus of claim 18 wherein the instructions that route the frame further comprise instructions that: determine, in dependence upon the egress bridge identifier, a next bridge in the network that is on a path from the bridge node to the egress bridge node; and route the frame to the next bridge node. ### Claim 22 (depends on 18) The apparatus of claim 18 wherein hardware of the ingress bridge node and hardware of the egress bridge node is incapable of mac-in-mac encapsulation. ### Claim 23 An apparatus for routing frames in a computer network using bridge identifiers, the computer network including a plurality of bridge nodes, at least one of the plurality of bridge nodes operating as an ingress bridge node through which the frames are received into the computer network, and at least one of the plurality of bridge nodes operating as an egress bridge node through which the frames are transmitted out of the computer network, the apparatus comprising: a computer memory storing a computer program, the computer program comprising instructions that: receive, by the ingress bridge node from a source node through another computer network, a frame, the frame specifying a source node address for the source node originating the frame, the frame specifying a destination node address for a destination node to which the frame is transmitted, retrieve, by the ingress bridge node, an ingress bridge identifier for the ingress bridge node, identify, by the ingress bridge node, an egress bridge identifier for the egress bridge node in dependence upon the destination node address specified by the frame, add, by the ingress bridge node, the ingress bridge identifier and the egress bridge identifier to the frame, and route, by the ingress bridge node, the frame through the computer network to the egress bridge node through which the destination node connects to the network; and a processor that executes the instructions. ### Claim 24 (depends on 23) The apparatus of claim 23 wherein hardware of the ingress bridge node and hardware of the egress bridge node are incapable of mac-in-mac encapsulation. ### Claim 25 An apparatus for routing frames in a computer network using bridge identifiers, the computer network including a plurality of bridge nodes, at least one of the plurality of bridge nodes operating as an ingress bridge node through which the frames are received into the computer network, and at least one of the plurality of bridge nodes operating as an egress bridge node through which the frames are transmitted out of the computer network, the apparatus comprising: a computer memory storing a computer program, the computer program comprising instructions that: receive, by one of the plurality of bridge nodes connected to the egress bridge node by a single hop, a frame for transmission to a destination node, the destination node connected to the network through the egress bridge node, and the frame having a shortest path bridging header that includes an ingress bridge nickname and an egress bridge nickname, determine, by the bridge node, that the frame traverses the egress bridge node on the next network hop, replace, by the bridge node in response to the determination, the shortest path bridging header with an ingress bridge identifier and an egress bridge identifier, and route, by the bridge node, the frame to the egress bridge node; and a processor that executes the instructions. ### Claim 26 (depends on 25) The apparatus of claim 25 wherein hardware of the ingress bridge node and hardware of the egress bridge node are incapable of mac-in-mac encapsulation. ### Claim 27 An apparatus for routing frames in a computer network using bridge identifiers, the computer network including a plurality of bridge nodes, at least one of the plurality of bridge nodes operating as an ingress bridge node through which the frames are received into the computer network, and at least one of the plurality of bridge nodes operating as an egress bridge node through which the frames are transmitted out of the computer network, the apparatus comprising: a computer memory storing a computer program, the computer program comprising instructions that: receive, by the egress bridge node from one of the plurality of bridge nodes, a frame for transmission to a destination node, the destination node connected to the network through the egress bridge node, and the frame including an ingress bridge identifier and an egress bridge identifier, remove, by the egress bridge node, the ingress bridge identifier and the egress bridge identifier from the frame, and route, by the egress bridge node, the frame for delivery to the destination node; and a processor that executes the instructions. ### Claim 28 (depends on 27) The apparatus of claim 27 wherein hardware of the ingress bridge node and hardware of the egress bridge node are incapable of mac-in-mac encapsulation. ### Claim 29 A computer-readable medium for routing frames in a computer network using bridge identifiers, the computer network including a plurality of bridge nodes, at least one of the plurality of bridge nodes operating as an ingress bridge node through which the frames are received into the computer network, and at least one of the plurality of bridge nodes operating as an egress bridge node through which the frames are transmitted out of the computer network, the computer-readable medium encoded with instructions that are executed by a processor in a data processing system to perform a method comprising the steps of: receiving, by one of the plurality of bridge nodes from the ingress bridge node, a frame for transmission to a destination node, the destination node connected to the network through the egress bridge node, the frame including an ingress bridge identifier and an egress bridge identifier; and routing, by the bridge node to the egress bridge node through which the destination node connects to the network, the frame in dependence upon the ingress bridge identifier and the egress bridge identifier included in the frame. ### Claim 30 (depends on 29) The computer-readable medium of claim 29 wherein the step of routing the frame further comprises the steps of: adding, to the frame in dependence upon the ingress bridge identifier and the egress bridge identifier, a shortest path bridging header conforming to a shortest path bridging protocol, the shortest path bridging header including an ingress bridge nickname and an egress bridge nickname, the ingress bridge nickname allocated to the ingress bridge node according to a predetermined protocol, the egress bridge nickname allocated to the egress bridge node according to the predetermined protocol; and routing the frame to the egress bridge node in dependence upon the ingress bridge nickname and the egress bridge nickname. ### Claim 31 (depends on 29) The computer-readable medium of claim 29 wherein the step of routing the frame further comprises the steps of: determining, in dependence upon the egress bridge identifier, a next bridge in the network that is on a path from the bridge node to the egress bridge node; and routing the frame to the next bridge node. ### Claim 32 (depends on 31) The computer-readable medium of claim 31 wherein hardware of the ingress bridge node and hardware of the egress bridge node are incapable of mac-in-mac encapsulation. ### Claim 33 A computer-readable medium for routing frames in a computer network using bridge identifiers, the computer network including a plurality of bridge nodes, at least one of the plurality of bridge nodes operating as an ingress bridge node through which the frames are received into the computer network, and at least one of the plurality of bridge nodes operating as an egress bridge node through which the frames are transmitted out of the computer network, the computer-readable medium encoded with instructions that are executed by a processor in a data processing system to perform a method comprising the steps of: receiving, by the ingress bridge node from a source node through another computer network, a frame, the frame specifying a source node address for the source node originating the frame, the frame specifying a destination node address for a destination node to which the frame is transmitted; retrieving, by the ingress bridge node, an ingress bridge identifier for the ingress bridge node; identifying, by the ingress bridge node, an egress bridge identifier for the egress bridge node in dependence upon the destination node address specified by the frame; adding, by the ingress bridge node, the ingress bridge identifier and the egress bridge identifier to the frame; and routing, by the ingress bridge node, the frame through the computer network to the egress bridge node through which the destination node connects to the network. ### Claim 34 (depends on 33) The computer-readable medium of claim 33 wherein hardware of the ingress bridge node and hardware of the egress bridge node are incapable of mac-in-mac encapsulation. ### Claim 35 A computer-readable medium for routing frames in a computer network using bridge identifiers, the computer network including a plurality of bridge nodes, at least one of the plurality of bridge nodes operating as an ingress bridge node through which the frames are received into the computer network, and at least one of the plurality of bridge nodes operating as an egress bridge node through which the frames are transmitted out of the computer network, the computer-readable medium encoded with instructions that are executed by a processor in a data processing system to perform a method comprising the steps of: receiving, by one of the plurality of bridge nodes connected to the egress bridge node by a single hop, a frame for transmission to a destination node, the destination node connected to the network through the egress bridge node, and the frame having a shortest path bridging header that includes an ingress bridge nickname and an egress bridge nickname; determining, by the bridge node, that the frame traverses the egress bridge node on the next network hop; replacing, by the bridge node in response to the determination, the shortest path bridging header with an ingress bridge identifier and an egress bridge identifier; and routing, by the bridge node, the frame to the egress bridge node. ### Claim 36 (depends on 35) The computer-readable medium of claim 35 wherein hardware of the ingress bridge node and hardware of the egress bridge node are incapable of mac-in-mac encapsulation. ### Claim 37 A computer-readable medium for routing frames in a computer network using bridge identifiers, the computer network including a plurality of bridge nodes, at least one of the plurality of bridge nodes operating as an ingress bridge node through which the frames are received into the computer network, and at least one of the plurality of bridge nodes operating as an egress bridge node through which the frames are transmitted out of the computer network, the computer-readable medium encoded with instructions that are executed by a processor in a data processing system to perform a method comprising the steps of: receiving, by the egress bridge node from one of the plurality of bridge nodes, a frame for transmission to a destination node, the destination node connected to the network through the egress bridge node, and the frame including an ingress bridge identifier and an egress bridge identifier; removing, by the egress bridge node, the ingress bridge identifier and the egress bridge identifier from the frame; and routing, by the egress bridge node, the frame for delivery to the destination node.