# US 10,454,819 B2 · Method and apparatus for pseudo-wire setup and maintenance using intermediate system to intermediate system (IS-IS) > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,454,819 B2 - Document ID: US10454819B2 - Status: Granted - Kind: B2 - Application number: 16/089,125 - Filed: 2016-05-31 - Published: 2019-03-28 - Granted: 2019-10-22 - Earliest claimed: 2016-03-31 - Assignees: Telefonaktiebolaget LM Ericsson (publ) - Applicants: Telefonaktiebolaget LM Ericsson (publ) - Inventors: Uma S. Chunduri; Kiran Sasidharan Pillai; Evgeny Tantsura - Web page: https://patentgrep.com/patent/US10454819B2 ## CPC - H04L 45/68: {Pseudowire emulation, e.g. IETF WG PWE3} - H04L 12/4633: {Interconnection of networks using encapsulation techniques, e.g. tunneling} - H04L 45/03: by updating link state protocols - H04L 45/036: Updating the topology between route computation elements, e.g. between OpenFlow controllers - H04L 45/04: {Interdomain routing, e.g. hierarchical routing} - H04L 45/50: using label swapping, e.g. multi-protocol label switch [MPLS] - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) ## Abstract A method is implemented by a first Provider Edge (PE) network device in a network to configure a pseudo-wire (PW) between the first PE network device and a second PE network device in the network using Intermediate System to Intermediate System (IS-IS). The method includes receiving a first LSP update flooded in the network by the second PE network device via IS-IS, where the first LSP update advertises the PW. The method further includes configuring a local forwarding information base with a local PW label associated with the PW such that the first PE network device forwards traffic encapsulated with the local PW label to an Attachment Circuit associated with the PW and flooding a second LSP update in the network via IS-IS that includes an indication that the first PE network device is ready to receive traffic from the second PE network device over the PW. ## Claims ### Claim 1 A method implemented by a first Provider Edge (PE) network device in a network to configure a pseudo-wire (PW) between the first PE network device and a second PE network device in the network using Intermediate System to Intermediate System (ISIS), the method comprising: receiving a first link-state protocol data unit (LSP) update flooded in the network by the second PE network device via IS-IS, wherein the first LSP update includes a PW association type-length-value (TLV) targeted to the first PE network device, wherein the PW association TLV includes a PW sub-TLV that advertises the PW; determining the first PE network device supports the PW and whether the first PE network device has previously advertised the PW to the second PE network device; and in response to determining that the first PE network device supports the PW and has previously advertised the PW to the second PE network device: configuring a local forwarding information base with a local PW label associated with the PW such that the first PE network device forwards traffic encapsulated with the local PW label to an Attachment Circuit (AC) associated with the PW and flooding a second LSP update in the network via IS-IS, wherein the second LSP update includes an indication that the first PE network device is ready to receive traffic from the second PE network device over the PW. ### Claim 2 (depends on 1) The method of claim 1, wherein the PW sub-TLV includes an indication of a remote PW label associated with the PW and an indication of whether the second PE network device is ready to receive traffic from the first PE network device over the PW. ### Claim 3 (depends on 2) The method of claim 2, further comprising: Determining whether the second PE network device is ready to receive traffic from the first PE network device over the PW based on the indication included in the PW sub-TLV of whether the second PE network device is ready to receive traffic from the first PE network device over the PW; and installing a forwarding path that forwards traffic received from the AC associated with the PW towards the second PE network device in response to determining that the second PE network device is ready to receive traffic from the first PE network device over the PW, wherein the forwarding path encapsulates the traffic received from the AC associated with the PW with the remote PW label. ### Claim 4 (depends on 1) The method of claim 1, wherein the PW sub-TLV includes an indication of a PW ID of the PW and an indication of a PW type of the PW, and wherein the first PE network device determines whether it supports the PW based on the PW ID of the PW and the PW type of the PW. ### Claim 5 (depends on 4) The method of claim 4, wherein the PW sub-TLV further includes an indication of a PW status of the PW. ### Claim 6 (depends on 1) The method of claim 1, further comprising: flooding a third LSP update in the network via IS-IS, wherein the third LSP update includes an indication that the PW is withdrawn. ### Claim 7 (depends on 6) The method of claim 6, wherein the indication that the PW is withdrawn is an omission of a PW sub-TLV that advertises the PW in the third LSP update. ### Claim 8 (depends on 6) The method of claim 6, wherein the indication that the PW is withdrawn is an explicit indication in the third LSP update that the PW is withdrawn. ### Claim 9 (depends on 6) The method of claim 6, wherein the indication that the PW is withdrawn is an indication in the third LSP update that the first PE network device does not support PW signaling using IS-IS. ### Claim 10 (depends on 6) The method of claim 6, wherein the indication that the PW is withdrawn is an omission of a PW association TLV targeted to the second PE network device in the third LSP update. ### Claim 11 (depends on 1) The method of claim 1, wherein the PW sub-TLV includes a PW interface parameters sub-TLV. ### Claim 12 (depends on 1) The method of claim 1, wherein the PW sub-TLV includes a PW extended status sub-TLV. ### Claim 13 (depends on 1) The method of claim 1, further comprising: flooding a third LSP update in the network via IS-IS, wherein the third LSP update includes an indication that the first PE network device has capability to support PW signaling using IS-IS. ### Claim 14 A first Provider Edge (PE) network device adapted to configure a pseudo-wire (PW) in a network between the first PE network device and a second PE network device in the network using Intermediate System to Intermediate System (IS-IS), the first PE network device comprising: a set of one or more processors and a non-transitory machine-readable storage medium, wherein the non-transitory machine-readable storage medium has a PW signaling module stored therein, which when executed by the set of one or more processors, causes the first PE network device to receive a first LSP update flooded in the network by the second PE network device via IS-IS, wherein the first LSP update includes a PW association type-length-value (TLV) targeted to the first PE network device, wherein the PW association TLV includes a PW sub-TLV that advertises the PW, determine whether the first PE network device supports the PW and whether the first PE network device has previously advertised the PW to the second PE network device, and in response to a determination that the first PE network device supports the PW and has previously advertised the PW to the second PE network device, configure a local forwarding information base with a local PW label associated with the PW such that the first PE network device forwards traffic encapsulated with the local PW label to an Attachment Circuit (AC) associated with the PW and flood a second LSP update in the network via IS-IS, wherein the second LSP update includes an indication that the first PE network device is ready to receive traffic from the second PE network device over the PW. ### Claim 15 (depends on 14) The first PE network device of claim 14, wherein the PW sub-TLV includes an indication of a remote PW label associated with the PW and an indication of whether the second PE network device is ready to receive traffic from the first PE network device over the PW. ### Claim 16 (depends on 15) The first PE network device of claim 15, wherein the PW signaling module, which when executed by the set of one or more processors, further causes the first PE network device to determine whether the second PE network device is ready to receive traffic from the first PE network device over the PW based on the indication included in the PW sub-TLV of whether the second PE network device is ready to receive traffic from the first PE network device over the PW and install a forwarding path that forwards traffic received from the AC associated with the PW towards the second PE network device in response to determining that the second PE network device is ready to receive traffic from the first PE network device over the PW, wherein the forwarding path encapsulates the traffic received from the AC associated with the PW with the remote PW label. ### Claim 17 A non-transitory machine-readable medium having computer code stored therein, which when executed by a set of one or more processors of a first Provider Edge (PE) network device in a network, causes the first PE network device to perform operations for configuring a pseudo-wire (PW) between the first PE network device and a second PE network device in the network using Intermediate System to Intermediate System (IS-IS), the operations comprising: receiving a first LSP update flooded in the network by the second PE network device via IS-IS, wherein the first LSP update includes a PW association type-length-value (TLV) targeted to the first PE network device, wherein the PW association TLV includes a PW sub-TLV that advertises the PW; determining whether the first PE network device supports the PW and whether the first PE network device has previously advertised the PW to the second PE network device; and in response to determining that the first PE network device supports the PW and has previously advertised the PW to the second PE network device: configuring a local forwarding information base with a local PW label associated with the PW such that the first PE network device forwards traffic encapsulated with the local PW label to an Attachment Circuit (AC) associated with the PW and flooding a second LSP update in the network via IS-IS, wherein the second LSP update includes an indication that the first PE network device is ready to receive traffic from the second PE network device over the PW. ### Claim 18 (depends on 17) The non-transitory machine-readable medium of claim 17, wherein the PW sub-TLV includes an indication of a remote PW label associated with the PW and an indication of whether the second PE network device is ready to receive traffic from the first PE network device over the PW. ### Claim 19 (depends on 18) The non-transitory machine-readable medium of claim 18, wherein the computer code, when executed by the set of one or more processors of the first PE network device, causes the first PE network device to perform further operations comprising: determining whether the second PE network device is ready to receive traffic from the first PE network device over the PW based on the indication included in the PW sub-TLV of whether the second PE network device is ready to receive traffic from the first PE network device over the PW; and installing a forwarding path that forwards traffic received from the AC associated with the PW towards the second PE network device in response to determining that the second PE network device is ready to receive traffic from the first PE network device over the PW, wherein the forwarding path encapsulates the traffic received from the AC associated with the PW with the remote PW label. ### Claim 20 (depends on 17) The non-transitory machine-readable medium of claim 17, wherein the PW sub-TLV includes a PW interface parameters sub-TLV. ### Claim 21 (depends on 17) The non-transitory machine-readable medium of claim 17, wherein the PW sub-TLV includes a PW extended status sub-TLV.