Content name resolution for information centric networking

• US 9,678,998 B2
• Filed: 02/28/2014
• Issued: 06/13/2017
• Est. Priority Date: 02/28/2014
• Status: Active Grant

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Sevilla, Spencer, Garcia-Luna-Aceves, Jose J., Mahadevan, Priya
• Primary Examiner(s): Hasan, Syed
• Assistant Examiner(s): Ahmed, Saba
• Application Number:
  US14/194,147
• Publication Number:
  US 20150248455A1
• Time in Patent Office: 1,201 Days
• Field of Search: 707736
• CPC Class Codes: G06F 16/22 Indexing; Data structures therefor; Storage structures
• CPC Class Codes: H04L 67/1004 Server selection for load balancing
• CPC Class Codes: H04L 67/1095 Replication or mirroring of data, e.g. scheduling or transport for data synchronisation between network nodes
• CPC Class Codes: H04L 67/568 Storing data temporarily at an intermediate stage, e.g. caching

Abstract

A content-name-resolution (CNR) system can resolve IP addresses for named data objects (NDOs) based on their name. During operation, a CNR server can receive a query from a client device for a source to a named data object. The query can include at least a name prefix for the named data object. The CNR server can identify a cache server that corresponds to the named data object'"'"'s name prefix, and determines one or more sources associated with the named data object'"'"'s name prefix. The CNR server then returns, to the client device, a query response that includes a network address for the cache server, and includes a content record specifying the one or more sources.

Claims

1. A computer-implemented method, comprising:

receiving, by a content-name-resolution (CNR) server, a query from a client device for a source to a named data object, wherein the query includes at least a hierarchically structured variable-length identifier (HSVLI), and wherein the HSVLI further comprises a variable number of components, ordered from a most general component to a most specific component, and wherein the most specific component includes a name for the named data object;

selecting, from a set of content records, wherein a respective content record comprises a respective content prefix and respective network addresses for one or more respective sources associated with the respective content prefix, a best-matching content record comprising a longest matching prefix of the HSVLI for the named data object, which further involves;

selecting a best-matching content record with-containing a longest name prefix matching a first contiguous subset of the ordered components of the HSVLI, including the most general component; and

responsive to identifying a second content record containing a longer name prefix matching a larger contiguous subset than the first contiguous subset, identifying the second content record as the best-matching content record; and

returning, to the client device, a query response that includes the best-matching content record comprising network addresses for the-one or more best-matching sources.

2. The method of claim 1, further comprising:

identifying a cache server that corresponds to an HSVLI prefix of the named data object, wherein the HSVLI prefix includes a contiguous subset of the ordered components of the HSVLI, including the most general component; and

generating the query response to also include an address to the cache server.

3. The method of claim 2, wherein identifying the cache server involves:

determining that a cache server has not been assigned to the named data object'"'"'s HSVLI prefix;

selecting a cache server for the HSVLI prefix; and

binding the content object'"'"'s HSVLI prefix to the selected cache server.

4. The method of claim 3, wherein selecting the cache server involves one or more of:

using a load-balancing function to select a cache server from a plurality of cache servers; and

using a hash function to compute, from the named data object'"'"'s HSVLI prefix, a hash value that identifies a cache server.

5. The method of claim 1, further comprising:

receiving, from a peer CNR server, a request for a content record associated with a second HSVLI prefix;

generating a base content record for the second HSVLI prefix;

selecting one or more content servers associated with the second HSVLI prefix, wherein the selected content servers are selected for the peer CNR server;

generating a second content record by updating the base content record to include the selected content servers; and

sending the content record to the peer CNR server.

6. The method of claim 1, further comprising generating a content record, wherein generating the content record involves:

generating a base content record for an HSVLI prefix, which includes a contiguous subset of the ordered components of the HSVLI, including the most general component;

selecting one or more cache servers associated with the HSVLI prefix; and

generating the content record by updating the base content record to include the selected content servers.

7. The method of claim 1, wherein the best-matching content record also includes at least one or more of:

the HSVLI including the name for the named data object;

an object security field for verifying the integrity of the named data object;

a content security field for verifying the integrity of the content record;

a content delivery protocol; and

a set of protocol attributes.

8. The method of claim 1, wherein the best-matching content record specifies, for each network address, a corresponding content delivery protocol and a set of protocol attributes.

9. The method of claim 1, wherein the best-matching content record specifies network addresses for two best-matching sources associated with the longest prefix, the best-matching sources sorted according to one or more of:

a hop count between the CNR server and the sources;

a physical distance between the CNR server and the sources;

a network latency between the CNR server and the sources;

an available network bandwidth to the sources;

a processing delay at the sources; and

an average load at the sources.

10. The method of claim 1, wherein obtaining a content record involves:

determining a remote content-name-resolution server associated with at least a portion of the HSVLI; and

sending, to the remote content-name-resolution server, a request for the content record associated with the portion of the HSVLI.

11. The method of claim 10, further comprising:

responsive to receiving the content record from the remote content-name-resolution server, storing the content record in association with the portion of the HSVLI.

12. A non-transitory computer-readable storage medium storing instructions that when executed by a computer cause the computer to perform a method, the method comprising:

receiving a query from a client device for a source to a named data object, wherein the query includes at least a hierarchically structured variable-length identifier (HSVLI), and wherein the HSVLI further comprises a variable number of components, ordered from a most general component to a most specific component, and wherein the most specific component includes a name for the named data object;

selecting, from a set of content records, wherein a respective content record comprises a respective content prefix and respective network addresses for one or more respective sources associated with the respective content prefix, a best-matching content record comprising a longest matching prefix of the HSVLI for the named data object, which further involves;

selecting a best-matching content record containing a longest name prefix matching a first contiguous subset of the ordered components of the HSVLI, including the most general component; and

responsive to identifying a second content record containing a longer name prefix matching a larger contiguous subset than the first contiguous subset, identifying the second content record as the best-matching content record; and

returning, to the client device, a query response that includes the best-matching content record comprising network addresses for one or more best-matching sources.

13. The storage medium of claim 12, wherein the method further comprises:

identifying a cache server that corresponds to an HSVLI prefix of the named data object, wherein the HSVLI prefix includes a contiguous subset of the ordered components of the HSVLI, including the most general component; and

generating the query response to also include an address to the cache server.

15. The storage medium of claim 12, further comprising:

receiving, from a peer CNR server, a request for a content record associated with a second HSVLI prefix;

generating a base content record for the second HSVLI prefix;

selecting one or more content servers associated with the second HSVLI prefix, wherein the selected content servers are selected for the peer CNR server;

generating a second content record by updating the base content record to include the selected content servers; and

sending the content record to the peer CNR server.

16. The storage medium of claim 12, further comprising generating a content record, wherein generating the content record involves:

generating a base content record for an HSVLI prefix, which includes a contiguous subset of the ordered components of the HSVLI, including the most general component;

selecting one or more cache servers associated with the HSVLI prefix; and

generating the content record by updating the base content record to include the selected content servers.

17. The storage medium of claim 12, wherein the best-matching content record also includes at least one or more of:

the HSVLI including the name for the named data object;

an object security field for verifying the integrity of the named data object;

a content security field for verifying the integrity of the content record;

a content delivery protocol; and

a set of protocol attributes.

18. The storage medium of claim 12, wherein obtaining a content record involves:

determining a remote content-name-resolution server associated with at least a portion of the HSVLI; and

sending, to the remote content-name-resolution server, a request for the content record associated with the portion of the HSVLI.

19. The storage medium of claim 18, further comprising:

responsive to receiving the content record from the remote content-name-resolution server, storing the content record in association with the portion of the HSVLI.

14. The storage medium of 13, wherein identifying the cache server involves:

determining that a cache server has not been assigned to the named data object'"'"'s HSVLI prefix;

selecting a cache server for the HSVLI prefix; and

binding the content object'"'"'s HSVLI prefix to the selected cache server.