# US 7,467,225 B2 · System, method and apparatus for network service load and reliability management > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 7,467,225 B2 - Document ID: US7467225B2 - Status: Granted - Kind: B2 - Application number: 10/842,856 - Filed: 2004-05-11 - Published: 2004-10-21 - Granted: 2008-12-16 - Earliest claimed: 1999-03-05 - Assignees: AT&T Corp. - Inventors: Nikolaos Anerousis; Gisli Hjalmtysson - Web page: https://patentgrep.com/patent/US7467225B2 ## CPC - H04L 61/35: {involving non-standard use of addresses for implementing network functionalities, e.g. coding subscription information within the address or functional addressing, i.e. assigning an address to a function} - H04L 61/00: Network arrangements, protocols or services for addressing or naming - H04L 67/1001: for accessing one among a plurality of replicated servers - H04L 67/1008: based on parameters of servers, e.g. available memory or workload (monitoring of computer activity G06F11/30) - H04L 67/101: based on network conditions - H04L 67/1021: based on client or server locations - H04L 67/51: Discovery or management thereof, e.g. service location protocol [SLP] or web services - H04L 67/10015: {Access to distributed or replicated servers, e.g. using brokers} - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) ## Abstract A method and system that enables a network and components of the network to be aware of the services existing at the edges of the network and to route connection requests for these services to appropriate servers within the network based on a variety of criteria. By making the network and network components service-aware, routing functions can be implemented in a more scalable and efficient way. ## Claims ### Claim 1 A system for network service load and reliability management, the system comprising: at least one first router that performs routing of at least one data packet based on an address associated with the data packet and a first routing policy for routing data packets based on a service associated with the at least one data packet; at least one host server providing the service associated with the at least one data packet; and a tunnel coupling the first router and the at least one server, wherein, a flow state corresponding to an application-level state at a terminal originating the data packets is maintained at the at least one first router for each data flow of data packets to direct the data flow of data packets into the tunnel coupling the first router and the at least one server so as to maintain consistency at the application level such that packets destined for the originating terminal from the host server do not have to travel through the at least one first router. ### Claim 2 (depends on 1) The system of claim 1, wherein the at least one server is one server of a plurality of servers, each coupled to the at least one first router via a plurality of links, respectively. ### Claim 3 (depends on 2) The system of claim 2, wherein the plurality of servers each provide the service associated with the at least one data packet. ### Claim 4 (depends on 3) The system of claim 3, wherein the address is a virtual host address corresponding to the service associated with the at least one packet. ### Claim 5 (depends on 1) The system of claim 1, wherein the at least one first router is part of a site specific router cluster. ### Claim 6 (depends on 1) The system of claim 1, further comprising: at least one second router that performs routing of the at least one data packet based on the address associated with the data packet and a second routing policy for routing data packets based on the service associated with the at least one data packet; and a link coupling the at least one first router and the at least one second router. ### Claim 7 (depends on 6) The system of claim 6, wherein the at least one first router is one first router of a plurality of first routers, each coupled to the at least one second router via a plurality of links, respectively. ### Claim 8 (depends on 7) The system of claim 7, wherein the plurality of first routers each can route the at least one packet to a server providing the service associated with the at least one data packet. ### Claim 9 (depends on 8) The system of claim 8, wherein the address is a virtual host address corresponding to the service associated with the at least one packet. ### Claim 10 (depends on 6) The system of claim 6, wherein the at least one second router is part of a system-specific router cluster. ### Claim 11 (depends on 6) The system of claim 6, further comprising: at least one third router that performs routing of the at least one data packet based on the address associated with the data packet and a third routing policy for routing data packets based on the service associated with the at least one data packet; and a link coupling the at least one third router and the at least one second router. ### Claim 12 (depends on 11) The system of claim 11, wherein the at least one third router is one third router of a plurality of second routers, each coupled to the at least one third router via a plurality of links, respectively. ### Claim 13 (depends on 12) The system of claim 12, wherein the plurality of second routers each can route the at least one packet to a server providing the service associated with the at least one data packet. ### Claim 14 (depends on 11) The system of claim 11, wherein the address is a virtual host address corresponding to the service associated with the at least one packet. ### Claim 15 (depends on 11) The system of claim 11, wherein the at least one third router is part of a network-level router cluster. ### Claim 16 A method for performing network service load and reliability management, the method comprising: routing at least one data packet from a first router to a server based on an address associated with the data packet and a routing policy for routing data packets based on a service associated with the at least one data packet, the data packet being routed through a tunnel coupling the first router and the server, wherein, a flow state corresponding to an application-level state at a terminal originating the data packets is maintained at the at least one first router for each data flow of data packets to direct the data flow of data packets into the tunnel coupling the first router and the at least one server so as to maintain consistency at the application level such that packets destined for the originating terminal from the host server do not have to travel through the at least one first router. ### Claim 17 (depends on 16) The method of claim 16, wherein the server is one server of a plurality of servers, each coupled to the first router via a plurality of links, respectively. ### Claim 18 (depends on 16) The method of claim 16, wherein the plurality of servers each provide the service associated with the at least one data packet. ### Claim 19 (depends on 18) The method of claim 18, wherein the address is a virtual host address corresponding to the service associated with the at least one packet. ### Claim 20 (depends on 16) The method of claim 16, wherein the first router is part of a site-specific router cluster. ### Claim 21 (depends on 16) The method of claim 16, further comprising: routing the at least one data packet from a second router to the first router based on the address associated with the data packet and a second routing policy for routing data packets based on the service associated with the at least one data packet. ### Claim 22 (depends on 21) The method of claim 21, wherein the first router is one first router of a plurality of first routers, each coupled to the second router via a plurality of links, respectively. ### Claim 23 (depends on 22) The method of claim 22, wherein the plurality of first routers each can route the at least one packet to a server providing the service associated with the at least one data packet. ### Claim 24 (depends on 21) The method of claim 21, wherein the address is a virtual host address corresponding to the service associated with the at least one packet. ### Claim 25 (depends on 21) The method of claim 21, wherein the second router is part of a system specific router cluster. ### Claim 26 (depends on 21) The method of claim 21, further comprising: routing the at least one data packet from a third router to the second router based on the address associated with the data packet and a third routing policy for routing data packets based on the service associated with the at least one data packet. ### Claim 27 (depends on 26) The method of claim 26, wherein the second router is one second router of a plurality of second routers, each coupled to the third router via a plurality of links, respectively. ### Claim 28 (depends on 27) The method of claim 27, wherein the plurality of second routers each can route the at least one packet to a server providing the service associated with the at least one data packet. ### Claim 29 (depends on 26) The method of claim 26, wherein the address is a virtual host address corresponding to the service associated with the at least one packet. ### Claim 30 (depends on 26) The method of claim 26, wherein the third router is part of a network-level router cluster.