# US 9,438,509 B2 · Default gateway redundancy support across SPB networks > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,438,509 B2 - Document ID: US9438509B2 - Status: Granted - Kind: B2 - Application number: 13/931,762 - Filed: 2013-06-28 - Published: 2015-01-01 - Granted: 2016-09-06 - Earliest claimed: 2013-06-28 - Assignees: Avaya Inc. - Applicants: Avaya Inc. - Inventors: Deepak Ramesh; Luigi Simonetti - Web page: https://patentgrep.com/patent/US9438509B2 ## CPC - H04L 45/12: Shortest path evaluation - H04L 45/66: {Layer 2 routing, e.g. in Ethernet based MAN's} - H04L 45/74: Address processing for routing - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) ## Abstract Methods, systems and computer readable media for default gateway redundancy support across SPB networks are described. In some implementations, the method can include enabling peer network information exchange on a per-network basis between a plurality of switches in a network and advertising a first address and a second address from each switch in the plurality of switches to the other switches. The method can also include storing, at each switch, the first address and the second address received from the other switches in the plurality of switches. The method can further include routing, at a first switch, traffic for a second switch when the first switch detects that the traffic can be routed more efficiently without being sent to the second switch. ## Claims ### Claim 1 A method comprising: enabling peer network information exchange via routed split multi-link trunking (RSMLT) over shortest path bridging (SPB) including non-inter switch trunk (IST) links on a per-network basis between a plurality of switches in a shortest path bridging mac-in-mac network; advertising a first address and a second address from each switch in the plurality of switches to the other switches via RSMLT over SPB; storing, at each switch, the first address and the second address received from the other switches in the plurality of switches; and routing, at a first switch, traffic for a second switch when the first switch detects that the traffic can be routed more efficiently through the shortest path bridging mac-in-mac network without being sent to the second switch. ### Claim 2 (depends on 1) The method of claim 1, wherein the first address is an Internet Protocol address and the second address is a MAC address. ### Claim 3 (depends on 1) The method of claim 1, further comprising: starting a hold down timer when one of the switches is rebooted; and forwarding traffic to a switch associated with the gateway for the traffic for the duration of the hold down timer. ### Claim 4 (depends on 1) The method of claim 1, wherein the first address and the second address received from the other switches in the plurality of switches are stored as long as an advertising switch associated with the first address and the second address is reachable through the network. ### Claim 5 (depends on 1) The method of claim 1, wherein a protocol used for the advertising is ISIS. ### Claim 6 (depends on 1) The method of claim 1, wherein the first address and the second address correspond to a gateway. ### Claim 7 A system comprising one or more processors configured to perform operations including: enabling peer network information exchange via routed split multi-link trunking (RSMLT) over shortest path bridging (SPB) including non-inter switch trunk (IST) links on a per-network basis between a plurality of switches in a shortest path bridging mac-in-mac network; advertising a first address and a second address from each switch in the plurality of switches to the other switches via RSMLT over SPB; storing, at each switch, the first address and the second address received from the other switches in the plurality of switches; and routing, at a first switch, traffic for a second switch when the first switch detects that the traffic can be routed more efficiently through the shortest path bridging mac-in-mac network without being sent to the second switch. ### Claim 8 (depends on 7) The system of claim 7, wherein the first address is an Internet Protocol address and the second address is a MAC address. ### Claim 9 (depends on 7) The system of claim 7, wherein the operations further comprise: starting a hold down timer when one of the switches is rebooted; and forwarding traffic to a switch associated with the gateway for the traffic for the duration of the hold down timer. ### Claim 10 (depends on 7) The system of claim 7, wherein the first address and the second address received from the other switches in the plurality of switches are stored as long as an advertising switch associated with the first address and the second address is reachable through the network. ### Claim 11 (depends on 7) The system of claim 7, wherein the first address and the second address correspond to a gateway. ### Claim 12 A nontransitory computer readable medium having stored thereon software instructions that, when executed by a processor of a wireless controller, cause the processor to perform operations including: enabling peer network information exchange via routed split multi-link trunking (RSMLT) over shortest path bridging (SPB) including non-inter switch trunk (IST) links on a per-network basis between a plurality of switches in a shortest path bridging mac-in-mac network; advertising a first address and a second address from each switch in the plurality of switches to the other switches via RSMLT over SPB; storing, at each switch, the first address and the second address received from the other switches in the plurality of switches; and routing, at a first switch, traffic for a second switch when the first switch detects that the traffic can be routed more efficiently through the shortest path bridging mac-in-mac network without being sent to the second switch. ### Claim 13 (depends on 12) The nontransitory computer readable medium of claim 12, wherein the first address is an Internet Protocol address and the second address is a MAC address. ### Claim 14 (depends on 12) The nontransitory computer readable medium of claim 12, wherein the operations further comprise: starting a hold down timer when one of the switches is rebooted; and forwarding traffic to a switch associated with the gateway for the traffic for the duration of the hold down timer. ### Claim 15 (depends on 12) The nontransitory computer readable medium of claim 12, wherein the first address and the second address received from the other switches in the plurality of switches are stored as long as an advertising switch associated with the first address and the second address is reachable through the network.