Meta-tagging in content routed networks

• US 20050138019A1
• Filed: 12/16/2004
• Published: 06/23/2005
• Est. Priority Date: 12/19/2003
• Status: Active Grant

• Current Assignee: Solace Corp.
• Original Assignee: Solace Systems, Inc. (United Kingdom)
• Inventors: Barnes, Martin, Ashton, Peter, Bertin, Greg, Pochopsky, David, Burwell, Wayne, Betts, Craig
• Granted Patent: US 7,526,493 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• 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 45/30 Routing of multiclass traffic
• CPC Class Codes: H04L 45/50 using label swapping, e.g. multi-protocol label switch [MPLS]

Abstract

A method of adding meta-data to document in a content-routed network including a plurality of routers interconnected by links involves adding an encoded meta-tag to the document.

Claims

1. A method of handling a document in a content-routed network including a plurality of content based routers interconnected by links, comprising:

preparing a document for transmission;

creating meta-data describing at least one or more characteristics of said document;

attaching said meta-data to the document;

receiving the document at one or more downstream routers;

analyzing the meta-data at one or more said downstream routers; and

handling the received document at said one or more downstream routers in accordance with said meta-data.

2. The method of claim 1, wherein said meta-data is created by examining an incoming document to be transmitted over said content-routed network.

3. The method of claim 1, wherein said meta-data is created by a publisher of said document.

4. The method of claim 1 wherein said meta-data is attached as an encoded meta-tag.

5. The method of claim 4, wherein said document is transmitted over an HTTP connection, and said meta-data is added to an HTTP header.

6. The method of claim 5, wherein said meta-data comprises a one or more meta-tags selected from the group consisting of:

a unique “

publisher ID”

meta-tag;

a priority meta-tag assigning a priority to said document;

a “

hops left”

meta-tag;

a “

traversed routers”

meta-tag;

an “

address”

meta-tag identifying at least the destination address of each content router that the document needs to be delivered to; and

an “

entitlement group”

meta-tag providing a list of entitlement groups which the document has been published into.

7. The method of claim 4, wherein said meta-tag is a unique to a particular publisher ID.

8. The method of claim 4, wherein said meta-tag is a priority meta-tag assigning a particular priority to said document whereby documents only need only to be priority classified at the edge of the network and downstream routers need only read the meta-tag to determine the priority of the document.

9. The method of claim 4, wherein said meta-tag is modified or removed in a receiving router before onward transmission.

10. The method of claim 9, wherein said meta-tag is a “

hops left”

meta-tag such that downstream routers can track the remaining number of network hops that the document is allowed to traverse.

11. The method as of claim 9, wherein said meta-tag is a “

Traversed Routers”

meta-tag to permit a downstream router to determine the list of routers that a document has passed through.

12. The method of claim 4, wherein said meta-tag is an “

address”

meta-tag carrying the addresses of source router or one or more destination routers for the document.

13. The method of claim 4, wherein said meta-tag is an “

entitlement group”

meta-tag controls which set of content subscribers are allowed to receive the document.

14. The method of claim 4, wherein said meta-tag is a “

checksum”

meta-tag which can be used to detect whether a document has become corrupted as it traverses the network.

15. The method of claim 4, wherein said meta-tag is a “

version”

meta-tag, which can be used to differentiate between old formats or semantics and a newer format or semantics of the meta-data.

16. The method of claim 4, wherein said document is XML encoded, and said meta-tags are attached to said XML document.

17. The method of claim 16, wherein said meta tag is an XML header (XMH) that is inserted by the first content router traversed by said document.

18. The method of claim 17, wherein said XML header is stripped from said document by the last content router that delivers the document to a subscriber.

19. The method of claim 3, wherein said publisher is attached to a said content-router, which is configured to augment, transform or remove the meta-data attached by the publisher.

20. The method of claim 1, wherein an egress content-based router is configured to supply some of the meta-data with the document, with possible transformation, when delivering said document to an attached subscriber.

21. The method of claim 1, wherein an egress content-based router delivering said document to an attached subscriber is configured to remove, replace or transform some meta-data items when sending a document over a link to a different administrative domain, or when receiving a document over a link from a different administrative domain.

22. A content-based router for use in a content-routed network including a plurality of such content based routers interconnected by links, comprising a processor configured:

to examine a document received from a publisher and which is to be transmitted over said content-routed network to determine one or more characteristics thereof;

to attach meta-data to the document describing at least said one or more characteristics determined from examining said document;

to accept, modify or remove any meta-data received from a publisher;

whereby one or more subsequent routers can analyze the meta-data and handle the received document in accordance with said meta-data describing said one or more characteristics.

23. The content-based router of claim 22, wherein said processor attaches said meta-data as an encoded meta-tag.

24. The content-based router of claim 23, wherein said router is configured to establish an HTTP connection over which said document is transmitted, and said processor is configured to add said meta-data to an HTTP header.

25. The content-based router of claim 24, wherein said processor is configured to add said meta tag to an XML document.

26. The content-based router of claim 25, wherein said meta tag is an XML header (XMH).

27. A method of handling a document in a content-routed network including a plurality of content based routers interconnected by links, comprising:

at a source router establishing an HTTP connection over which said document is to be transmitting;

attaching meta-data in an HTTP header determining the handling of said document in one or more downstream routers;

receiving the document at one or more downstream routers;

analyzing the meta-data at one or more said downstream routers; and

handling the received document at said one or more downstream routers in accordance with said meta-data.

28. The method of claim 27, wherein said meta-data is modified or removed in a receiving router before onward transmission.

29. The method of claim 28, wherein said meta-data is attached as an encoded meta-tag.