# US 9,438,558 B2 · Link-local multicast in WLAN deployments > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,438,558 B2 - Document ID: US9438558B2 - Status: Granted - Kind: B2 - Application number: 14/033,448 - Filed: 2013-09-21 - Published: 2015-03-26 - Granted: 2016-09-06 - Earliest claimed: 2013-09-21 - Assignees: Avaya Inc. - Applicants: Avaya Inc. - Inventors: Shashi Hosakere Ankaiah; Vivek L. Atreya; Seemant Choudhary - Web page: https://patentgrep.com/patent/US9438558B2 ## CPC - H04L 61/5069: for group communication, multicast communication or broadcast communication - H04L 12/1886: {with traffic restrictions for efficiency improvement, e.g. involving subnets or subdomains} - H04L 12/4633: {Interconnection of networks using encapsulation techniques, e.g. tunneling} - H04L 12/4641: {Virtual LANs, VLANs, e.g. virtual private networks [VPN] (LAN interconnection over a bridge based backbone H04L12/462; encapsulation techniques H04L12/4633; routing of packets H04L45/00; packet switches H04L49/00; virtual private networks for security H04L63/0272)} - H04W 84/12: WLAN [Wireless Local Area Networks] - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) - H04W: WIRELESS COMMUNICATION NETWORKS (broadcast communication H04H; communication systems using wireless links for non-selective communication, e.g. wireless extensions H04M1/72) ## Abstract Some implementations can include a method including reserving a range of multicast addresses for handling link-local multicasts and generating a multicast group within the range for each VLAN. The method can also include subscribing at an access point to a corresponding multicast group for a VLAN when a client associates with the access point, and tunneling link local multicast traffic from the client to a WSP component via an access tunnel. The method can further include forwarding the link local multicast traffic from the WSP component to subscribing access points. ## Claims ### Claim 1 A method comprising: reserving a range of multicast addresses for handling link-local multicasts within a network; generating a multicast group within the range for each VLAN; subscribing at an access point to a corresponding multicast group for a VLAN when a client associates with the access point; tunneling link local multicast traffic from the client to a WSP component via an access tunnel; and forwarding the link local multicast traffic from the WSP component to subscribing access points, wherein the forwarding includes: encapsulating frame using a generated multicast group for the received VLAN; forwarding the frame to members in the generated multicast group for that VLAN; receiving the frame at access points subscribed to the group; and decapsulating the frame at the access points and forwarding the frame to clients subscribed to an inner multicast group. ### Claim 2 (depends on 1) The method of claim 1, wherein the range includes an administratively scoped multicast group range. ### Claim 3 (depends on 1) The method of claim 1, wherein subscribing includes sending an IGMP join message for the corresponding multicast group. ### Claim 4 (depends on 1) The method of claim 1, wherein the network includes a plurality of WSP components. ### Claim 5 (depends on 4) The method of claim 4, further comprising electing one of the plurality of WSP components as a gateway WSP for each VLAN. ### Claim 6 (depends on 5) The method of claim 5, wherein the gateway WSP component receives link local multicast traffic on the VLAN and transmits on a multicast group for that VLAN. ### Claim 7 A system comprising one or more processors configured to perform operations including: reserving a range of multicast addresses for handling link-local multicasts within a network; generating a multicast group within the range for each VLAN; subscribing at an access point to a corresponding multicast group for a VLAN when a client associates with the access point; tunneling link local multicast traffic from the client to a WSP component via an access tunnel; and forwarding the link local multicast traffic from the WSP component to subscribing access points wherein the forwarding includes: encapsulating frame using a generated multicast group for the received VLAN; forwarding the frame to members in the generated multicast group for that VLAN; receiving the frame at access points subscribed to the group; and decapsulating the frame at the access points and forwarding the frame to clients subscribed to an inner multicast group. ### Claim 8 (depends on 7) The system of claim 7, wherein the range includes an administratively scoped multicast group range. ### Claim 9 (depends on 7) The system of claim 7, wherein subscribing includes sending an IGMP join message for the corresponding multicast group. ### Claim 10 (depends on 7) The system of claim 7, wherein the network includes a plurality of WSP components. ### Claim 11 (depends on 10) The system of claim 10, further comprising electing one of the plurality of WSP components as a gateway WSP for each VLAN. ### Claim 12 (depends on 11) The system of claim 11, wherein the gateway WSP component receives link local multicast traffic on the VLAN and transmits on a multicast group for that VLAN. ### Claim 13 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: reserving a range of multicast addresses for handling link-local multicasts within a network; generating a multicast group within the range for each VLAN; subscribing at an access point to a corresponding multicast group for a VLAN when a client associates with the access point; tunneling link local multicast traffic from the client to a WSP component via an access tunnel; and forwarding the link local multicast traffic from the WSP component to subscribing access points wherein the forwarding includes: encapsulating frame using a generated multicast group for the received VLAN; forwarding the frame to members in the generated multicast group for that VLAN; receiving the frame at access points subscribed to the group; and decapsulating the frame at the access points and forwarding the frame to clients subscribed to an inner multicast group. ### Claim 14 (depends on 13) The nontransitory computer readable medium of claim 13, wherein the range includes an administratively scoped multicast group range. ### Claim 15 (depends on 13) The nontransitory computer readable medium of claim 13, wherein subscribing includes sending an IGMP join message for the corresponding multicast group. ### Claim 16 (depends on 13) The nontransitory computer readable medium of claim 13, wherein the network includes a plurality of WSP components. ### Claim 17 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: reserving a range of multicast addresses for handling link-local multicasts within a network; generating a multicast group within the range for each VLAN; subscribing at an access point to a corresponding multicast group for a VLAN when a client associates with the access point; tunneling link local multicast traffic from the client to a WSP component via an access tunnel; forwarding the link local multicast traffic from the WSP component to subscribing access points; and electing one of the plurality of WSP components as a gateway WSP for each VLAN, and the gateway WSP component receives link local multicast traffic on the VLAN and transmits on a multicast group for that VLAN, wherein the network includes a plurality of WSP components.