Adjusting entries in a forwarding information base in a content centric network

• US 9,832,116 B2
• Filed: 03/14/2016
• Issued: 11/28/2017
• Est. Priority Date: 03/14/2016
• Status: Active Grant

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Wood, Christopher A., Scott, Glenn C.
• Primary Examiner(s): Harper, Kevin C
• Application Number:
  US15/069,628
• Publication Number:
  US 20170264536A1
• Time in Patent Office: 624 Days
• CPC Class Codes: G06F 15/17306 Intercommunication techniques
• CPC Class Codes: G06Q 10/06 Resources, workflows, human or project management; Enterprise or organisation planning; Enterprise or organisation modelling
• CPC Class Codes: H04L 43/0864 Round trip delays
• CPC Class Codes: H04L 45/02 Topology update or discovery
• CPC Class Codes: H04L 45/54 Organization of routing tables
• CPC Class Codes: H04L 45/74591 using content-addressable memories [CAM]
• CPC Class Codes: H04L 67/1097 for distributed storage of data in networks, e.g. transport arrangements for network file system [NFS], storage area networks [SAN] or network attached storage [NAS]
• CPC Class Codes: H04L 67/63 Routing a service request depending on the request content or context

Abstract

One embodiment provides a system that facilitates dynamic adjustment of forwarding information in a CCN. During operation, the system receives, by forwarding circuitry, an interest with a name that is a hierarchically structured variable length identifier which comprises contiguous name components ordered from a most general level to a most specific level. The system identifies in a first data structure an entry for one or more name components of the name, wherein the entry includes a list of outgoing interfaces associated with the one or more name components. The system determines network properties in response to forwarding the interest to a first interface of the list. The system reorders the list in order of priority based on the network properties, thereby facilitating the forwarding circuitry to dynamically adjust a likelihood of using a respective interface for forwarding interests associated with the one or more name components.

Claims

1. A computer system, the system comprising:

a processor;

a storage device coupled to the processor and storing instructions that when executed by a computer cause the computer to perform a method, the method comprising;

receiving, by forwarding circuitry, an interest with a name that is a hierarchically structured variable length identifier which comprises contiguous name components ordered from a most general level to a most specific level;

identifying in a first data structure an entry for one or more name components of the name, wherein the entry includes a list of outgoing interfaces associated with the one or more name components;

determining network properties in response to forwarding the interest to a first interface of the list of outgoing interfaces; and

reordering the list of outgoing interfaces in order of priority based on the network properties, thereby facilitating the forwarding circuitry to dynamically adjust a likelihood of using a respective interface for forwarding interests associated with the one or more name components.

2. The computer system of claim 1, wherein the method further comprises:

selecting a second interface from the reordered list; and

forwarding the interest to the second interface.

3. The computer system of claim 1, wherein determining the network properties further comprises:

recording a round trip time that begins when the interest is forwarded to the first interface and ends when a responsive content object is received from the first interface; and

wherein the method further comprises reordering the list to indicate that a higher priority is based on a shorter round trip time for a respective interface.

4. The computer system of claim 1, wherein determining the network properties further comprises:

receiving from the first interface an interest return message which indicates an error condition; and

wherein the method further comprises reordering the list to indicate that the first interface is of a lower priority than a second interface which has a recorded round trip time,

wherein a round trip time begins when the interest is forwarded to the second interface and ends when a responsive content object is received from the second interface.

5. The computer system of claim 1, wherein the first data structure is a forwarding information base, and wherein an entry in the forwarding information base further includes, for a respective interface of the list of outgoing interfaces, one or more of:

an indicator of a round trip time that begins when the interest is forwarded to the first interface and ends when a responsive content object is received from the first interface;

an indicator of receipt of an interest return message which indicates an error condition; and

an indicator of a timeout of an entry in a pending interest table, wherein the timeout indicates that a responsive content object to the interest has not been received before an expiration of the entry.

6. The computer system of claim 1, wherein the one or more name components comprise a name prefix, and wherein the one or more name components are contiguous name components beginning from the most general level.

7. The computer system of claim 1, wherein determining the network properties further comprises:

in response to detecting in a second data structure a timeout of an entry for the interest after forwarding the interest to the first interface;

removing the first interface from the list;

or

reordering the first interface to a lowest priority in the list.

8. The computer system of claim 7, wherein the second data structure is a pending interest table, and wherein an entry in the pending interest table includes the interest name, a list of incoming interfaces from which the interest is received, a list of outgoing interfaces to which the interest is forwarded, and an expiry time which indicates a lifetime for the entry in the pending interest table.

9. The computer system of claim 1, wherein the method further comprises:

calculating a weight for each outgoing interface based on the network properties; and

reordering the list to indicate that a higher priority is based on a greater calculated weight for a respective interface.

10. The computer system of claim 9, wherein calculating the weight further comprises:

performing a function based on network properties determined over a period of time, wherein the period of time is a predetermined value or a user-defined value.

11. A computer-implemented method, comprising:

receiving, by forwarding circuitry, an interest with a name that is a hierarchically structured variable length identifier which comprises contiguous name components ordered from a most general level to a most specific level;

identifying in a first data structure an entry for one or more name components of the name, wherein the entry includes a list of outgoing interfaces associated with the one or more name components;

determining network properties in response to forwarding the interest to a first interface of the list of outgoing interfaces; and

reordering the list of outgoing interfaces in order of priority based on the network properties, thereby facilitating the forwarding circuitry to dynamically adjust a likelihood of using a respective interface for forwarding interests associated with the one or more name components.

12. The method of claim 11, further comprising:

selecting a second interface from the reordered list; and

forwarding the interest to the second interface.

13. The method of claim 11, wherein determining the network properties further comprises:

recording a round trip time that begins when the interest is forwarded to the first interface and ends when a responsive content object is received from the first interface; and

wherein the method further comprises reordering the list to indicate that a higher priority is based on a shorter round trip time for a respective interface.

14. The method of claim 11, wherein determining the network properties further comprises:

receiving from the first interface an interest return message which indicates an error condition; and

wherein the method further comprises reordering the list to indicate that the first interface is of a lower priority than a second interface which has a recorded round trip time,

wherein a round trip time begins when the interest is forwarded to the second interface and ends when a responsive content object is received from the second interface.

15. The method of claim 11, wherein the first data structure is a forwarding information base, and wherein an entry in the forwarding information base further includes, for a respective interface of the list of outgoing interfaces, one or more of:

an indicator of a round trip time that begins when the interest is forwarded to the first interface and ends when a responsive content object is received from the first interface;

an indicator of receipt of an interest return message which indicates an error condition; and

an indicator of a timeout of an entry in a pending interest table, wherein the timeout indicates that a responsive content object to the interest has not been received before an expiration of the entry.

16. The method of claim 11, wherein the one or more name components comprise a name prefix, and wherein the one or more name components are contiguous name components beginning from the most general level.

17. The method of claim 11, wherein determining the network properties further comprises:

in response to detecting in a second data structure a timeout of an entry for the interest after forwarding the interest to the first interface;

removing the first interface from the list;

or

reordering the first interface to a lowest priority in the list.

18. The method of claim 17, wherein the second data structure is a pending interest table, and wherein an entry in the pending interest table includes the interest name, a list of incoming interfaces from which the interest is received, a list of outgoing interfaces to which the interest is forwarded, and an expiry time which indicates a lifetime for the entry in the pending interest table.

19. The method of claim 11, further comprising:

calculating a weight for each outgoing interface based on the network properties; and

reordering the list to indicate that a higher priority is based on a greater calculated weight for a respective interface.

20. The method of claim 19, wherein calculating the weight further comprises:

performing a function based on network properties determined over a period of time, wherein the period of time is a predetermined value or a user-defined value.