DISTRIBUTED CACHE SYSTEM FOR OPTICAL NETWORKS

• US 20140052814A1
• Filed: 08/14/2012
• Published: 02/20/2014
• Est. Priority Date: 08/14/2012
• Status: Active Grant

• Current Assignee: Calix Incorporated
• Original Assignee: Calix Incorporated
• Inventors: Graham, Norman B.
• Granted Patent: US 9,137,326 B2
• Time in Patent Office: Days
• US Class Current: 709/217
• CPC Class Codes: G06F 16/9574 of access to content, e.g. by caching
• CPC Class Codes: H04L 67/2885 Hierarchically arranged intermediate devices, e.g. for hierarchical caching
• CPC Class Codes: H04L 67/51 Discovery or management thereof, e.g. service location protocol [SLP] or web services
• CPC Class Codes: H04L 67/568 Storing data temporarily at an intermediate stage, e.g. caching
• CPC Class Codes: H04Q 11/0067 Provisions for optical access or distribution networks, e.g. Gigabit Ethernet Passive Optical Network (GE-PON), ATM-based Passive Optical Network (A-PON), PON-Ring

Abstract

Caching techniques are described. An example network device positioned between an optical line terminal (OLT) and a service provider device includes a hot cache, a wide cache controller, and a control unit. The control unit is configured to receive, from a first service delivery platform, a request for digital content, and determine whether the requested digital content is stored on the hot cache. The control unit is further configured to, when the requested digital content is not stored on the hot cache, determine, using the wide cache controller, whether the requested digital content is stored on a wide cache of a second service delivery platform, receive, from the second service delivery platform, the requested digital content, and responsive to the request received from the first delivery platform, send the received digital content to the first delivery platform.

Claims

1. A method comprising:

receiving, by a network device positioned between an optical line terminal (OLT) and a service provider device, a request for digital content from a first service delivery platform;

determining, by the network device, whether the requested digital content is stored on a hot cache of the network device;

when the requested digital content is not stored on the hot cache, determining, by the network device, whether the requested digital content is stored on a wide cache of a second service delivery platform;

when the requested digital content is stored on the wide cache of the second service delivery platform, sending, by the network device, a backup request for the requested digital content to the second service delivery platform;

receiving, by the network device and from the second service delivery platform, the requested digital content; and

sending, by the network device, the received digital content to the first service delivery platform.

2. The method of claim 1, further comprising:

when the requested digital content is stored on the hot cache, transmitting the requested digital content to the first service delivery platform.

3. The method of claim 1, further comprising:

responsive to receiving the request from the first service delivery platform, incrementing an impact rating (IR) associated with the requested digital content.

4. The method of claim 3, further comprising:

comparing the incremented IR to a threshold value; and

when the incremented IR exceeds the threshold value and the requested digital content is not stored on the hot cache, storing, to the hot cache, the received digital content.

5. The method of claim 4, wherein the threshold value is equal to the lowest IR of data currently stored on the hot cache.

6. The method of claim 1, further comprising:

when the requested digital content is not stored on the wide cache of the second service delivery platform, sending the backup request to the service provider device.

7. The method of claim 1, wherein the first service delivery platform is a first optical network unit (ONU) and the second service delivery platform is a second ONU.

8. The method of claim 1, wherein determining whether the requested digital content is stored on the wide cache of the second service delivery platform comprises determining whether the requested digital content is stored on the wide cache of the second service delivery platform based on a stored reference to the wide cache of the second service delivery platform.

9. The method of claim 8, wherein the reference comprises a pointer.

10. The method of claim 1, wherein the digital content comprises at least one of video data and audio data.

11. A network device positioned between an optical line terminal (OLT) and a service provider device, the network device comprising:

a hot cache configured to store digital content;

a wide cache controller configured to store one or more references to digital content stored on a plurality of SDPs; and

a control unit configured to;

receive, from a first service delivery platform of the plurality of SDPs, a request for digital content;

determine whether the requested digital content is stored on the hot cache;

when the requested digital content is not stored on the hot cache, determine, using the wide cache controller, whether the requested digital content is stored on a wide cache of a second service delivery platform of the plurality of SDPs;

receive, from the second service delivery platform, the requested digital content; and

responsive to the request received from the first service delivery platform, send the received digital content to the first delivery platform.

12. The network device of claim 11, wherein the control unit is further configured to:

when the requested digital content is stored on the hot cache, transmit the requested digital content to the first service delivery platform.

13. The network device of claim 11, wherein the control unit is further configured to:

increment, responsive to receiving the request from the first service delivery platform, an impact rating (IR) associated with the requested digital content.

14. The network device of claim 13, wherein the control unit is further configured to:

compare the incremented IR to a threshold value; and

store to the hot cache, when the incremented IR exceeds the threshold value and the requested digital content is not stored on the hot cache, the received digital content.

15. The network device of claim 14, wherein the threshold value is equal to the lowest IR of data currently stored on the hot cache.

16. The network device of claim 11, wherein the control unit is further configured to:

send, when the requested digital content is not stored on the wide cache of the second service delivery platform, the backup request to the service provider device.

17. The network device of claim 11, wherein the wide cache controller is configured to store a pointer to a storage address of the wide cache of the second service delivery platform, and wherein the storage address is associated with the requested digital content.

18. The network device of claim 11, wherein the digital content comprises one or both of video data and audio data.

19. A computer-readable storage device comprising instructions that, when executed, cause one or more programmable processors of a network device to:

receive a request for digital content from a first service delivery platform communicatively coupled to the network device;

determine whether the requested digital content is stored on a hot cache of the network device;

when the requested digital content is not stored on the hot cache, determine, using a wide cache controller of the network device, whether the requested digital content is stored on a wide cache of a second service delivery platform communicatively coupled to the network device;

when the requested digital content is stored on the wide cache of the second service delivery platform, send a backup request for the requested digital content to the second service delivery platform;

receive, from the second service delivery platform, the requested digital content; and

send the received digital content to the first service delivery platform.

20. A network device positioned between an optical line terminal (OLT) and a service provider device, the network device comprising:

means for receiving a request for digital content from a first service delivery platform;

means for determining whether the requested digital content is stored on a hot cache of the network device;

means for determining, when the requested digital content is not stored on the hot cache, whether the requested digital content is stored on a wide cache of a second service delivery platform;

means for sending, when the requested digital content is stored on the wide cache of the second service delivery platform, a backup request for the requested digital content to the second service delivery platform;

means for receiving, from the second service delivery platform, the requested digital content; and

means for sending the received digital content to the first service delivery platform.

21. A method comprising:

receiving, by a service delivery platform and from a subscriber device communicatively coupled to the service delivery platform, a request that identifies digital content;

responsive to receiving the request, determining whether the digital content is stored on a wide cache of the service delivery platform; and

when the digital content is not stored on the wide cache,

forwarding the received request to a network device;

receiving, from the network device, the requested digital content, wherein the received digital content comprises at least one of

     1) digital content stored on a hot cache of the network device, and

     2) digital content that is stored on another wide cache of another service delivery platform and that is sent from the another service delivery platform via the network device; and

forwarding the received digital content to the subscriber device.

22. The method of claim 21, wherein the service delivery platform is an optical network unit (ONU).

23. The method of claim 21, wherein the digital content comprises one or both of video data and audio data.

24. The method of claim 21, further comprising:

when the digital content is stored on the wide cache, sending the requested digital content to the subscriber device.

25. The method of claim 21, further comprising:

responsive to receiving the request, incrementing an impact rating (IR) of the digital content; and

if the incremented IR of the received digital content is greater than a threshold value, storing the received digital content to the wide cache.

26. The method of claim 25, wherein storing the received digital content to the wide cache further comprises:

selecting at least one stored item of digital content that is currently stored on the wide cache; and

deleting the selected at least one stored item of digital content from the wide cache.

27. The method of claim 26, wherein selecting the at least one stored item of digital content further comprises:

selecting a stored item of digital content from a plurality of stored items of digital content, wherein the selected stored item of digital content has a lowest impact rating (IR) of all stored items of the plurality of stored items of digital content.

28. The method of claim 25, further comprising:

calculating an IR of the digital content based at least in part on one or more of;

     1) a count of all requests for the digital content on a current day,

     2) a sum of total hits associated with the digital content within a predetermined time window,

     3) a size of all content currently stored on the wide cache, and

     4) a factor to differentiate between two or more different types of digital content.

29. The method of claim 25, wherein storing the received digital content to the wide cache further comprises:

comparing a size of the received digital content with a size of a competing received digital content, wherein the received digital content and the competing received digital content share an equal IR; and

based at least in part on the comparison, selecting the received digital content to store to the wide cache.

30. A service delivery platform comprising:

an optical network interface;

a wide cache; and

a control unit configured to;

receive, at the optical network interface and from a network device positioned between the service delivery platform and a service provider device, a backup request that identifies digital content;

determine whether the identified digital content is stored on the wide cache;

when the identified digital content is stored on the wide cache, send the identified digital content from the optical network interface to the network device positioned between the service delivery platform and the service provider device.

31. A computer-readable storage device comprising instructions that, when executed, cause one or more programmable processors of a service delivery platform to:

receive, from a subscriber device communicatively coupled to the service delivery platform, a request that identifies digital content;

responsive to receiving the request, determine whether the digital content is stored on a wide cache of the service delivery platform; and

when the digital content is not stored on the wide cache,

forward the received request to a network device;

receive, from the network device, the requested digital content, wherein the received digital content comprises at least one of

     1) digital content stored on a hot cache of the network device, and

     2) digital content that is stored on another wide cache of another service delivery platform and that is sent from the another service delivery platform via the network device; and

forward the received digital content to the subscriber device.

32. A service delivery platform comprising:

means for receiving, from a subscriber device communicatively coupled to the service delivery platform, a request that identifies digital content;

means for determining, responsive to receiving the request, whether the digital content is stored on a wide cache of the service delivery platform; and

means for, when the digital content is not stored on the wide cache,

forwarding the received request to a network device;

receiving, from the network device, the requested digital content, wherein the received digital content comprises at least one of

     1) digital content stored on a hot cache of the network device, and

     2) digital content that is stored on another wide cache of another service delivery platform and that is sent from the another service delivery platform via the network device; and

forwarding the received digital content to the subscriber device.