# US 2019/0173835 A1 · Hybrid Unicast/Anycast Content Distribution Network System > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2019/0173835 A1 - Document ID: US20190173835A1 - Status: Published application - Kind: A1 - Application number: 16/252,204 - Filed: 2019-01-18 - Published: 2019-06-06 - Earliest claimed: 2008-11-11 - Assignees: AT&T Intellectual Property II, L.P. - Applicants: At&T Intellectual Property II, L.P. - Inventors: Alexandre Gerber; Oliver Spatscheck; Jacobus Van der Merwe - Web page: https://patentgrep.com/patent/US20190173835A1 ## CPC - H04L 61/5007: Internet protocol [IP] addresses - H04L 67/1001: for accessing one among a plurality of replicated servers - H04L 67/1021: based on client or server locations - H04L 67/568: Storing data temporarily at an intermediate stage, e.g. caching - H04L 61/58: Caching of addresses or names - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) ## Abstract A method includes receiving a request for an edge cache address, and comparing a requestor address to an anycast group. The method can further include providing an anycast edge cache address when the requestor address is in the anycast group. Alternatively, the method can further include determining an optimal cache server, and providing a unicast address of the optimal cache server when the requestor address is not in the anycast group. ## Claims ### Claim 1 A system comprising: a memory that stores instructions; and a processor that executes the instructions to perform operations, the operations comprising: comparing an address of a requestor to an anycast group, wherein when the anycast group is in a stable network, an existing relationship causes requests from the anycast group to enter the network at a same router, and wherein when the anycast group is in an unstable network, the traffic enters the network at multiple provider edge routers. ### Claim 2 (depends on 1) The system of claim 1, wherein the operations further comprise receiving, from the requestor, a request for an edge cache address of a cache server. ### Claim 3 (depends on 2) The system of claim 2, wherein the operations further comprise providing, to the requestor, the edge cache address as an anycast address when the address of the requestor is in the anycast group. ### Claim 4 (depends on 1) The system of claim 1, wherein the operations further comprise determining an optimal cache server for the requestor. ### Claim 5 (depends on 1) The system of claim 1, wherein the operations further comprise utilizing the address of the requestor to determine an optimal edge cache router for the requestor. ### Claim 6 (depends on 1) The system of claim 1, wherein the existing relationship relates to regulating how traffic enters a network that includes a cache server. ### Claim 7 (depends on 1) The system of claim 1, wherein the operations further comprise selecting an optimal cache server for the requestor based on a network distance, a network cost, an available bandwidth, an available server capacity, or a combination thereof. ### Claim 8 (depends on 7) The system of claim 7, wherein the operations further comprise providing, to the requestor, a unicast address for the optimal cache server selected. ### Claim 9 (depends on 1) The system of claim 1, wherein the operations further comprise determining an optimal cache server for the requestor when the requestor is not a member of the anycast group. ### Claim 10 (depends on 1) The system of claim 1, wherein the operations further comprise altering a route in a network to a cache server having an anycast address for requests coming from the anycast group. ### Claim 11 A method, comprising: comparing, by utilizing instructions from a memory that are executed by a processor, an address of a requestor to an anycast group, wherein when the anycast group is in a stable network, an existing relationship causes requests from the anycast group to enter the network at a same router, and wherein when the anycast group is in an unstable network, the traffic enters the network at multiple provider edge routers. ### Claim 12 (depends on 11) The method of claim 11, further comprising receiving, from the requestor, a request for an edge cache address of a cache server. ### Claim 13 (depends on 12) The method of claim 12, further comprising providing, to the requestor, the edge cache address as an anycast address when the address of the requestor is in the anycast group. ### Claim 14 (depends on 11) The method of claim 11, further comprising determining that the requestor is a member of the anycast group if the address of the requestor is in the anycast group. ### Claim 15 (depends on 11) The method of claim 11, further comprising determining an optimal cache server based on the address of the requestor. ### Claim 16 (depends on 11) The method of claim 11, further comprising selecting an optimal cache server for the requestor based on a network distance, a network cost, an available bandwidth, an available server capacity, or a combination thereof. ### Claim 17 (depends on 11) The method of claim 11, further comprising altering a route in a network to a cache server having an anycast address for requests coming from the anycast group. ### Claim 18 (depends on 11) The method of claim 11, further comprising determining an optimal cache server for the requestor when the requestor is not a member of the anycast group. ### Claim 19 A non-transitory computer-readable device comprising instructions, which, when loaded and executed by a processor, cause the processor to perform operations, the operations comprising: comparing an address of a requestor to an anycast group, wherein when the anycast group is in a stable network, an existing relationship causes requests from the anycast group to enter the network at a same router, and wherein when the anycast group is in an unstable network, the traffic enters the network at multiple provider edge routers. ### Claim 20 (depends on 19) The non-transitory computer-readable device of claim 19, wherein the operations further comprise selecting an optimal cache server for the requestor based on a network distance, a network cost, an available bandwidth, an available server capacity, or a combination thereof.