Automatic mapping of an IPv6 packet in multi-topology routing

• US 20070127474A1
• Filed: 12/02/2005
• Published: 06/07/2007
• Est. Priority Date: 12/02/2005
• Status: Abandoned Application

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Roy, Abhay, Mirtorabi, Sina
• Application Number:
  US11/292,535
• Publication Number:
  US 20070127474A1
• Time in Patent Office: Days
• US Class Current: 370/390
• CPC Class Codes: H04L 45/00 Routing or path finding of packets in data switching networks routing or path finding in wireless networks H04W40/00
• CPC Class Codes: H04L 45/26 Route discovery packet
• CPC Class Codes: H04L 47/10 Flow control; Congestion control
• CPC Class Codes: H04L 47/2408 for supporting different services, e.g. a differentiated services [DiffServ] type of service

Abstract

The present invention provides automatic classification of an IPv6 packet to a given topology. A topology identifier is carried as an embedded field in the interface ID portion of an IPv6 address. Automatic classification of an IPv6 packet for a given topology prevents manual configuration in intermediate nodes. Further, it remedies the value limit problem of differentiated services code points (DSCPs) and re-use of DSCP values within each topology.

Claims

1. A method of routing an IPv6 packet in a multi-topology routing network, comprising:

receiving an IPv6 packet;

reading a multi-topology identifier contained in the IPv6 packet, the multi-topology identifier indicating a logical topology of devices within a network having a plurality of logical topologies;

inspecting a local table to find a logical topology of devices in a network, the logical topology associated with the multi-topology identifier contained in the IPv6 packet; and

sending the received IPv6 packet to the logical topology of devices.

2. The method of claim 1, wherein the logical topology comprises a subgroup of routers in a network of routers.

3. The method of claim 1, wherein the IPv6 packet is marked to indicate that it is handled by multi-topology aware routers.

4. The method of claim 1, wherein the IPv6 packet contains a destination address, the destination address having a type that indicates that the destination address includes a multi-topology identifier.

5. The method of claim 1, wherein inspecting a local table to find a logical topology of devices comprises identifying a communication path across a plurality of routers that reaches the logical topology of devices.

6. A method of routing an IPv6 packet in a multi-topology routing network, comprising:

inserting a multi-topology identifier in a destination address portion of an IPv6 packet, the multi-topology identifier identifying one of a plurality of logical topologies of devices in a network; and

sending the IPv6 packet to a router within the network.

7. The method of claim 6, wherein the presence of the multi-topology identifier is indicated by a type definition, the type definition comprising an interface identifier using an IANA OUI assignment.

8. The method of claim 7, wherein the IANA OUI assignment comprises a type field the type field indicating that a field next to the type field contains a multi-topology identifier.

9. A computer-readable medium containing instructions which, when executed by a computer, route an IPv6 packet in a multi-topology routing network, by:

receiving an IPv6 packet;

reading a multi-topology identifier contained in the IPv6 packet, the multi-topology identifier indicating a logical topology of devices within a network having a plurality of logical topologies;

inspecting a local table to find a logical topology of devices in a network, the logical topology associated with the multi-topology identifier contained in the IPv6 packet; and

sending the received IPv6 packet to the logical topology of devices.

10. A computer-readable medium containing instructions which, when executed by a computer, route an IPv6 packet in a multi-topology routing network, by:

inserting a multi-topology identifier in a destination address portion of an IPv6 packet, the multi-topology identifier identifying one of a plurality of logical topologies of devices in a network; and

sending the IPv6 packet to a router within the network.

11. A router, comprising:

means for receiving an IPv6 packet;

means for reading a multi-topology identifier contained in the IPv6 packet, the multi-topology identifier indicating a logical topology of devices within a network having a plurality of logical topologies;

means for inspecting a local table to find a logical topology of devices in a network, the logical topology associated with the multi-topology identifier contained in the IPv6 packet; and

means for sending the received IPv6 packet to the logical topology of devices.

12. A router, comprising:

means for inserting a multi-topology identifier in a destination address portion of an IPv6 packet, the multi-topology identifier identifying one of a plurality of logical topologies of devices in a network; and

means for sending the IPv6 packet to a router within the network.