CONTENT SET BASED DELTACASTING

• US 20100179986A1
• Filed: 01/12/2010
• Published: 07/15/2010
• Est. Priority Date: 01/13/2009
• Status: Active Grant

• Current Assignee: ViaSat Incorporated
• Original Assignee: ViaSat Incorporated
• Inventors: Sebastian, William B., Lepeska, Peter
• Granted Patent: US 8,489,672 B2
• Time in Patent Office: Days
• US Class Current: 709/203
• CPC Class Codes: H04B 7/185 Space-based or airborne stations; Stations for satellite systemsH04B7/204 takes precedence
• CPC Class Codes: H04L 12/1859 adapted to provide push services, e.g. data channels
• CPC Class Codes: H04L 12/1863 comprising mechanisms for improved reliability, e.g. status reports arrangements for detecting or preventing errors by carrying supervisory signal the return channel H04L1/16
• CPC Class Codes: H04L 12/1881 with schedule organisation, e.g. priority, sequence management
• CPC Class Codes: H04L 12/1886 with traffic restrictions for efficiency improvement, e.g. involving subnets or subdomains
• CPC Class Codes: H04L 45/7453 using hashing
• CPC Class Codes: H04L 47/70 Admission control; Resource allocation
• CPC Class Codes: H04L 65/60 Network streaming of media packets
• CPC Class Codes: H04L 65/611 for multicast or broadcast systems for broadcast or conference H04L12/18; arrangements for broadcast or distribution combined with broadcast H04H20/00; arrangements for broadcast applications with a direct linkage to broadcast information or to broadcast space-time H04H60/00; selective distribution of broadcast services, e.g. multimedia broadcast multicast service [MBMS], H04W4/06
• CPC Class Codes: H04L 67/01 Protocols
• CPC Class Codes: H04L 67/10 in which an application is distributed across nodes in the network software deployment G06F8/60; multiprogramming arrangements G06F9/46
• CPC Class Codes: H04L 69/04 Protocols for data compression, e.g. ROHC
• CPC Class Codes: H04L 69/22 Parsing or analysis of headers

Abstract

Methods, apparatuses, and systems are provided for improving utilization of the satellite communications system through various “deltacasting” techniques for handling content sets (e.g., feeds or websites). Embodiments operate in a client-server context, including a server optimizer, a client optimizer, and, in some embodiments, a pre-positioning client. Within this client-server context, content sets are multicast (e.g., anticipatorily pre-positioned in a local dictionary) to end users of the communications system and are handled at the content set level, according to set-level metadata and/or user preferences. In some embodiments, when locally stored information from the content sets is requested by a user, deltacasting techniques are used to generate fingerprints for use in identifying and exploit multicasting and/or other opportunities for increased utilization of links of the communications system.

Claims

1. A method for multicasting over a communications system having a communications path between a server side of the communications system and a plurality of clients, the communications path comprising a shared forward link over which bandwidth resources are shared during a multicast communication, the method comprising:

intercepting a data block at the server side of the communications system, the data block comprising a header portion and a content portion and being communicated as part of a content set over the communications path, the content set comprising a plurality of content objects and being identified by a content set identifier;

associating the data block with the content set identifier;

generating a fingerprint using byte-level information comprised by the content portion of the data block;

determining whether to multicast the data block over the communications path according to the fingerprint; and

when it is determined to multicast the data block;

multicasting the data block over the communications path; and

using the content set identifier to determine whether a client accepts the data block multicast over the communications path.

2. The method of claim 1, wherein using the content set identifier to determine whether the client accepts the data block multicast over the communications path comprises:

determining, at the server side of the communications system, whether to include the client in a multicast group,

wherein the data block is multicast over the communications path according to the multicast group.

3. The method of claim 2, further comprising:

detecting a link condition affecting communications over the communications path with at least a portion of the multicast group; and

selecting a modcode as a function of the link condition,

wherein the data block is multicast over the communications path further according to the modcode.

4. The method of claim 1, wherein using the content set identifier to determine whether the client accepts the data block multicast over the communications path comprises:

determining, at the client, whether to locally store the data block according to the content set identifier.

5. The method of claim 1, wherein:

the content set identifier is associated with a set-level profile configured to characterize the content set; and

using the content set identifier to determine whether the client accepts the data block multicast over the communications path comprises determining whether the client accepts the data block according to at least a portion of the set-level profile.

6. The method of claim 5, wherein the set-level profile comprises set-level metadata.

7. The method of claim 1, further comprising:

receiving a request for the content set at the server side of the communications system;

downloading a set of content objects in response to receiving the request for the content set; and

associating the set of content objects with the content set identifier,

wherein the data block is intercepted as part of downloading the set of content objects.

8. The method of claim 1, wherein the content set identified by the content set identifier is configured to comprise all data blocks downloaded from a predetermined host.

9. The method of claim 1, wherein the content set identified by the content set identifier dynamically changes along with changes to the content objects comprised by the content set.

10. The method of claim 1, wherein determining whether to multicast the data block over the communications path according to the fingerprint comprises:

using the fingerprint to determine whether the data block matches byte-level information being communicated to a second client over the communications path via an active session stream.

11. The method of claim 1, wherein determining whether to multicast the data block over the communications path according to the fingerprint comprises:

using the fingerprint to determine whether the traffic is currently stored in a client dictionary configured to store data local to the client.

12. The method of claim 1, wherein the content set comprises a content feed.

13. The method of claim 1, wherein the content set comprises a webpage.

14. The method of claim 1, wherein the communications path comprises a satellite link.

15. A method for handling content multicast over a communications system having a communications path between a server side of the communications system and a plurality of clients, the communications path comprising a shared forward link over which bandwidth resources are shared during a multicast communication, the method comprising:

receiving a data block at a client of the communications system, the data block comprising a header portion and a content portion and having been multicast to the client over the communications path as a result of determining whether to multicast the data block according to a fingerprint generated using byte-level information comprised by the content portion of the data block, and the data block being associated with a content set identifier identifying a content set comprising a plurality of content objects; and

determining, at the client, whether to store the data block in a client dictionary according to the content set identifier.

16. The method of claim 15, wherein:

the content set identifier is associated with a set-level profile configured to characterize the content set; and

the determining, at the client, whether to store the data block in the client dictionary according to the content set identifier comprises determining whether to store the data block according to at least a portion of the set-level profile.

17. The method of claim 15, further comprising:

when it is determined to store the data block in a client dictionary according to the content set identifier, storing the data block in the client dictionary in association with the content set identifier, the content set identifier being associated with a set-level profile configured to characterize the content set.

18. The method of claim 17, further comprising:

determining, at the client, whether to remove stored data from the client dictionary according to a respective content set identifier.

19. The method of claim 17, further comprising:

generating a dictionary profile configured to characterize contents of the client dictionary according to the set-level profiles associated with the content set identifiers stored in association with the contents of the client dictionary; and

rendering web browser content at the client according to the dictionary profile.

20. The method of claim 17, further comprising:

receiving a request for a content set; and

calculating a compression gain metric for the content set as a function of content set identifiers stored in association with contents of the client dictionary.

21. The method of claim 15, further comprising:

issuing a request for the content set from the client,

wherein the data block is received as part of downloading the plurality of content objects comprised by the content set in response to the request for the content set.

22. The method of claim 21, wherein issuing the request comprises selecting a link through a web interface.

23. A server system for multicasting over a communications system having a communications path between a server side of the communications system and a plurality of clients, the communications path comprising a shared forward link over which bandwidth resources are shared during a multicast communication, the server system comprising:

an optimizer module, located at the server side of the communications system, and configured to;

intercept a data block comprising a header portion and a content portion and being communicated as part of a content set over the communications path, the content set comprising a plurality of content objects and being identified by a content set identifier;

associate the data block with the content set identifier; and

generate a fingerprint using byte-level information comprised by the content portion of the data block; and

a communications module, communicatively coupled with the optimizer module, and configured to;

determine whether to multicast the data block over the communications path according to the fingerprint; and

when it is determined to multicast the data block;

multicast the data block over the communications path; and

use the content set identifier to determine whether a client accepts the data block multicast over the communications path.

24. The server system of claim 23, wherein the communications module is configured to use the content set identifier to determine whether the client accepts the data block multicast over the communications path by:

determining whether to include the client in a multicast group, wherein the data block is multicast over the communications path according to the multicast group.

25. The server system of claim 24, wherein the communications module is further configured to use the content set identifier to determine whether the client accepts the data block multicast over the communications path by:

detecting a link condition affecting communications over the communications path with at least a portion of the multicast group; and

selecting a modcode as a function of the link condition, the data block being multicast over the communications path further according to the modcode.

26. The server system of claim 23, further comprising:

a content set generator module, communicatively coupled with the optimizer module, and configured to;

receive a request for the content set;

download a set of content objects in response to receiving the request for the content set; and

associate the set of content objects with the content set identifier,

wherein the data block is intercepted by the optimizer module as part of downloading the set of content objects.

27. A client system for handling content multicast over a communications system having a communications path between a server side of the communications system and a plurality of clients, the communications path comprising a shared forward link over which bandwidth resources are shared during a multicast communication, the client system comprising:

an optimizer module, located at a client of the communications system, and configured to receive a data block at the client of the communications system, the data block comprising a header portion and a content portion and having been multicast to the client over the communications path as a result of determining whether to multicast the data block according to a fingerprint generated using byte-level information comprised by the content portion of the data block, and the data block being associated with a content set identifier identifying a content set comprising a plurality of content objects; and

a dictionary management module, communicatively coupled with the optimizer module and a client dictionary, and configured to determine whether to store the data block in the client dictionary according to the content set identifier.

28. The client system of claim 27, wherein:

the content set identifier is associated with a set-level profile configured to characterize the content set; and

the dictionary management module is configured to determine whether to store the data block in the client dictionary according to at least a portion of the set-level profile.

29. The client system of claim 27, wherein the dictionary management module is further configured to:

store the data block in the client dictionary in association with the content set identifier when it is determined to store the data block in the client dictionary according to the content set identifier, the content set identifier being associated with a set-level profile configured to characterize the content set.

30. The client system of claim 29, wherein the dictionary management module is further configured to:

determine whether to remove stored data from the client dictionary according to a respective content set identifier.

31. The client system of claim 29, further comprising:

a web browser, communicatively coupled with the dictionary management module, and configured to;

render web browser content according to a dictionary profile configured to characterize contents of the client dictionary according to the set-level profiles associated with the content set identifiers stored in association with the contents of the client dictionary.

32. The client system of claim 31, wherein the web browser is further configured to:

issue a request for the content set in response to receiving a selection of a link associated with the content set,

wherein the data block is received as part of downloading the plurality of content objects comprised by the content set in response to the request for the content set.

33. The client system of claim 27, further comprising:

a compression management module, communicatively coupled with the client dictionary, and configured to;

calculate a compression gain metric for a requested content set as a function of content set identifiers stored in association with contents of the client dictionary.