Proximity-based redirection system for robust and scalable service-node location in an internetwork

• US 20030105865A1
• Filed: 07/01/2002
• Published: 06/05/2003
• Est. Priority Date: 09/03/1999
• Status: Active Grant

• Current Assignee: Google LLC (Alphabet Inc.)
• Original Assignee: FastForward Networks, Inc. (Apollo Global Management, Inc.)
• Inventors: Destein, William C., McCanne, Steven
• Granted Patent: US 6,901,445 B2
• Time in Patent Office: Days
• US Class Current: 709/225
• CPC Class Codes: H04L 12/18 for broadcast or conference , e.g. multicast
• CPC Class Codes: H04L 45/22 Alternate routing
• CPC Class Codes: H04L 45/306 Route determination based on the nature of the carried application
• CPC Class Codes: H04L 67/1001 for accessing one among a plurality of replicated servers
• CPC Class Codes: H04L 67/1008 based on parameters of servers, e.g. available memory or workload monitoring of computer activity G06F11/30
• CPC Class Codes: H04L 67/101 based on network conditions
• CPC Class Codes: H04L 67/1029 using data related to the state of servers by a load balancer
• CPC Class Codes: H04L 69/329 in the application layer [OSI layer 7]
• CPC Class Codes: H04L 9/40 Network security protocols

Abstract

A proximity-oriented redirection system for service-to-client attachment in a virtual overlay distribution network. The virtual overlay distribution network includes addressable routers for routing packet traffic, wherein a packet of data is routed from a source node to a destination node based on address fields of the packet. The invention includes a redirector coupled to at least one of the addressable routers and includes: logic for accepting a service request from a client; logic for determining a selected server for handling the service request, the selected server being one of a plurality of servers that can handle the service request; and logic for generating a redirection message directed to the client for redirecting the service request to the selected server.

Claims

1. In a packet-switched network including addressable routers for routing packet traffic, wherein a packet of data is routed from a source node to a destination node based on address fields of the packet, an improvement comprising:

a redirector coupled to at least one of the addressable routers, the redirector including;

A) logic for accepting a service request from a client, wherein the service request is an anycast message to an anycast destination address;

B) logic for determining a selected server for handling the service request, the selected server being one of a plurality of servers that can handle the service request; and

C) logic for generating a redirection message directed to the client for redirecting the service request to the selected server.

2. The redirector of claim 1 further comprising logic to advertise reachability to the anycast destination address.

3. The redirector of claim 1 wherein the logic for determining comprises:

logic for monitoring a network traffic condition of the plurality of servers; and

logic for selecting the selected server from the plurality of servers based on the network traffic condition.

4. The redirector of claim 1 wherein the logic for determining comprises:

logic for monitoring a server condition of the plurality of servers; and

logic for selecting the selected server from the plurality of servers based on the server condition.

5. The packet-switched network of claim 1, wherein the selected server is a multicasting server.

6. The packet-switched network of claim 1, wherein the redirector is the selected server.

7. A method of operating a redirector in a packet-switched network including addressable routers for routing packet traffic, wherein a packet of data is routed from a source node to a destination node based on address fields of the packet, the method comprising:

advertising reachability to an anycast destination address from the redirector;

accepting a service request from a client, wherein the service request is an anycast message to the anycast destination address;

determining a selected server for handling the service request, the selected server being one of a plurality of servers that can handle the service request; and

generating a redirection message directed to the client for redirecting the service request to the selected server.

8. The method of claim 7 further comprising a step of monitoring a traffic condition of the plurality of servers.

9. The method of claim 8 wherein the step of determining comprises a step of determining the selected server from the plurality of servers based on the traffic condition.

10. The method of claim 7 further comprising a step of monitoring a server condition of the plurality of servers.

11. The method of claim 10 wherein the step of determining comprises a step of determining the selected server from the plurality of servers based on the server condition.

12. The method of claim 7 further comprising a step of handling the service request at the redirector.

13. The method of claim 7 wherein the step of generating comprises a step of generating a redirection message directed to the client for redirecting the client to subscribe to a multicast group at the selected server.

14. A packet-switched network including addressable routers for routing packet traffic, wherein a packet of data is routed from a source node to a destination node based on address fields of the packet, the packet-switched network comprising:

at least one service node coupled to at least first one of the addressable routers and having logic to propagate data packets between a client and a plurality of nodes in an anycast group; and

at least one redirector coupled to at least a second one of the addressable routers, the at least one redirector comprising;

A) logic for advertising reachability to an anycast destination address associated with the plurality of nodes in the anycast group;

B) logic for accepting a service request from the client, wherein the service request is an anycast message to the anycast destination address; and

C) logic for generating a redirection message directed to the client for redirecting the service request to the at least one service node.

15. The packet-switched network of claim 14 wherein the at least one service node comprises a plurality of service nodes and the at least one redirector comprises:

logic to determine a selected service node from the plurality of service nodes for handling the service request; and

logic for generating a redirection message directed to the client for redirecting the service request to the selected service node.

16. The packet-switched network of claim 15 wherein the logic to determine the selected service node from the plurality of service nodes comprises:

logic to monitor a network traffic condition at the plurality of service nodes; and

logic to select the selected service node from the plurality of service nodes based on the network traffic condition.

17. The packet-switched network of claim 15 wherein the logic to determine the selected service node from the plurality of service nodes comprises:

logic to monitor a server condition at the plurality of service nodes; and

logic to select the selected service node from the plurality of service nodes based on the server condition.

18. The packet-switched network of claim 14, wherein a first portion of the plurality of nodes in the anycast group are located at a first geographic location, and wherein a second portion of the plurality of nodes in the anycast group are located at a second geographic location, the redirector further comprising:

logic for determining whether the client sending the anycast service request is closer to the first portion of nodes in the anycast group or the second portion of nodes in the anycast group; and

logic for generating the redirection message directed to the client for redirecting the service request to a first service node if the client is closer to the first portion of nodes in the anycast group and for redirecting the service request to a second service node if the client is closer to the second portion of nodes in the anycast group.

19. A method of operating a packet-switched network including addressable routers for routing packet traffic, wherein a packet of data is routed from a source node to a destination node based on address fields of the packet, and wherein the packet-switched network includes a redirector coupled to at least one of the addressable routers and at least one service node, the method comprising:

advertising reachability to an anycast destination address from the redirector;

accepting a service request from a client at the redirector, wherein the service request is an anycast message to the anycast destination address; and

generating a redirection message directed to the client for redirecting the service request to the at least one service node.

20. The method of claim 19 wherein the at least one service node comprises a plurality of service nodes, and the step of generating comprises steps of:

determining a selected service node from the plurality of service nodes for handling the service request; and

generating a redirection message directed to the client for redirecting the service request to the selected service node.

21. The method of claim 20 wherein the step of determining comprises steps of:

monitoring a network traffic condition at the plurality of service nodes; and

selecting the selected service node from the plurality of service nodes based on the network traffic condition.

22. The method of claim 20 wherein the step of determining comprises steps of:

monitoring a server condition at the plurality of service nodes; and

selecting the selected service node from the plurality of service nodes based on the server condition.

23. The method of claim 19, wherein a first portion of the plurality of nodes in the anycast group are located at a first geographic location, and wherein a second portion of the plurality of nodes in the anycast group are located at a second geographic location, and the step of generating comprising steps of:

determining whether the client sending the anycast service request is closer to the first portion of nodes in the anycast group or the second portion of nodes in the anycast group; and

generating the redirection message directed to the client for redirecting the service request to a first service node if the client is closer to the first portion of nodes in the anycast group and for redirecting the service request to a second service node if the client is closer to the second portion of nodes in the anycast group.