DIRECTORY SERVICES CACHING FOR NETWORK PEER TO PEER SERVICE LOCATOR

• US 20030067912A1
• Filed: 07/02/1999
• Published: 04/10/2003
• Est. Priority Date: 07/02/1999
• Status: Active Grant

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: DENNY, MARK, BALES, SCOTT, LAUTMANN, JOHN, MEAD, ANDREW, THIPPESWAMY, ARUNKUMAR
• Granted Patent: US 6,680,942 B2
• Time in Patent Office: Days
• US Class Current: 370/389
• 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 61/10 of different types
• CPC Class Codes: H04L 61/4517 using open systems interconnection [OSI] directories, e.g. X.500
• CPC Class Codes: H04L 61/4523 using lightweight directory access protocol [LDAP]

Abstract

A new directory service is established for a peer router receiving a data packet from an end station on a local area network connected to a port of the peer router, the peer router hereinafter being referred to as the source router. The data packet is addressed to a destination address. The source router determines that the data packet is to be encapsulated as an encapsulated packet, and the encapsulated packet routed by a peer-to-peer protocol to a destination router. The destination router then transmits the packet onto a local area network to the destination address. The source router locates the proper peer destination router by use of a database. The database is maintained on a server, where the database has entries for destination address, and an entry for a particular destination address gives the address of a peer router capable of routing a packet to that particular destination address. The database is populated by peer routers updating the database with information concerning the destination address which the peer routers can reach. The database on the server is interrogated by the source router to learn the address of a destination peer router, and an encapsulated packet is then transmitted onto a connectionless network for transmission to the destination router. The peer-to-peer routing protocol may be DLSw protocol. The database may be maintained in accordance with the X.500 directory standard. The database may be interrogated using the lightweight data access protocol (LDAP).

Claims

1. A method of routing a data packet addressed to a destination address, comprising:

receiving said data packet by a source router;

determining, by said source router, that said data packet is to be encapsulated as an encapsulated packet, and said encapsulated packet routed by a peer-to-peer protocol to a destination router;

maintaining a database on a server, said database having entries for destination addresses, an entry for a particular destination addresses giving the address of a router capable of routing a packet to said particular destination addresses;

interrogating said database on said server by said source router to learn the address of a destination router, said destination router capable of routing a packet to said destination addresses;

addressing, in response to information received from said database connecting said destination address with said destination router, said encapsulated packet to said destination router; and

,

transmitting said encapsulated packet onto a connectionless network for transmission to said destination router.

2. The method as in claim 1 further comprising:

maintaining said database in a directory service running on a convenient computer.

3. The method as in claim 1 further comprising:

interrogating said database with a lightweight data access protocol (LDAP).

4. The method as in claim 1 further comprising:

determining that said peer-to-peer routing protocol is DLSw protocol.

5. The method as in claim 1 further comprising:

encapsulating said data with an SSP header.

6. The method as in claim 1 wherein said transmitting step further comprises:

transmitting said encapsulated packet according a connection-oriented protocol.

7. The method as in claim 6 further comprising:

transmitting said encapsulated packet according to a TCP/IP connection-oriented protocol.

8. The method as in claim 1 further comprising:

receiving said encapsulated packet by said destination router;

transmitting by said destination router, in response to receiving said encapsulated packet, a destination packet onto a computer network having said destination address connected thereto, said destination packet addressed to said destination address.

9. The method as in claim 1 wherein said maintaining said database further comprising:

maintaining said database in accordance with an X.500 standard.

10. The method as in claim 1 further comprising:

searching by said source router, in response to information received from said database that said destination address is not found, for a destination router capable of reaching said destination address;

receiving by said source router information connecting said destination address with a name of a destination router capable of reaching said destination address;

transmitting said encapsulated packet onto a connectionless network for transmission to said destination router.

11. The method as in claim 10 further comprising:

updating said database with said information connecting said destination address with a name of a destination router capable of reaching said destination address.

12. The method as in claim 10 wherein said searching step further comprises:

transmitting by said source router a message asking peer routers if they can reach said destination address.

20. A computer readable media containing a computer program to perform the method of claim 1.

21. Electromagnetic signals on a computer network to perform the method of claim 1.

13. The method as in step 1 further comprising:

saving said destination address in a reachability table as a Layer 2 address of an end station.

14. The method as in step 1 further comprising:

saving said destination address in a reachability table as an address of a process in a destination end station.

15. The method as in step 1 further comprising:

saving said destination address in a reachability table as an address of a logical unit in a SNA network.

16. A method of routing a data packet addressed to a destination address, comprising:

receiving said data packet by a source router;

determining, by said source router, that said data packet is to be encapsulated as an encapsulated packet, and said encapsulated packet routed by a peer-to-peer protocol to a destination router;

maintaining a database on a server, said database having entries for destination addresses, an entry for a particular destination addresses giving the address of a router capable of routing a packet to said particular destination addresses;

interrogating said database on said server by said source router to learn the address of a destination router, said destination router capable of routing a packet to said destination addresses;

addressing, in response to information received from said database connecting said destination address with said destination router, said encapsulated packet to said destination router; and

,

transmitting said encapsulated packet onto a connectionless network for transmission to said destination router;

searching by said source router, in response to information received from said database that said destination address is not found, for a destination router capable of reaching said destination address;

receiving by said source router information connecting said destination address with a name of a destination router capable of reaching said destination address;

transmitting said encapsulated packet onto a connectionless network for transmission to said destination router; and

,

updating said database with said information connecting said destination address with a name of a destination router capable of reaching said destination address.

17. The method as in claim 16 wherein said searching step further comprises:

transmitting by said source router a message asking peer routers if they can reach said destination address.

18. An apparatus to route a data packet addressed to a destination address, comprising:

means for receiving said data packet by a source router;

means for determining, by said source router, that said data packet is to be encapsulated as an encapsulated packet, and said encapsulated packet routed by a peer-to-peer protocol to a destination router;

means for maintaining a database on a server, said database having entries for destination addresses, an entry for a particular destination addresses giving the address of a router capable of routing a packet to said particular destination addresses;

means for interrogating said database on said server by said source router to learn the address of a destination router, said destination router capable of routing a packet to said destination addresses;

means for addressing, in response to information received from said database connecting said destination address with said destination router, said encapsulated packet to said destination router; and

,

means for transmitting said encapsulated packet onto a connectionless network for transmission to said destination router.

19. An apparatus to route a data packet addressed to a destination address, comprising:

a receiver in a source router to receive said data packet;

a header field examining apparatus in said source router, to determine that said data packet is to be encapsulated as an encapsulated packet, and said encapsulated packet routed by a peer-to-peer protocol to a destination router;

a database on a server, said database having entries for destination addresses, an entry for a particular destination addresses giving the address of a router capable of routing a packet to said particular destination addresses;

a first transmitter and protocol stack to interrogate said database on said server by said source router to learn the address of a destination router, said destination router capable of routing a packet to said destination addresses, said transmitter to send an inquiry message to said database;

a protocol stack to address, in response to information received from said database connecting said destination address with said destination router, said encapsulated packet to said destination router; and

,

a second transmitter and protocol stack to transmit said encapsulated packet onto a connectionless network for delivery to said destination router.

22. A data structure in a computer memory, comprising:

a database, said database having entries for destination addresses, an entry for a particular destination address giving the address of a destination router capable of routing a packet to a computer having said particular destination address, where an entry found in said database enables a source router to address an encapsulated packet containing a desired data packet to a desired destination router, an address of said desired destination router learned from said database, and said desired destination router de-encapsulating said encapsulated packet to recover said desired data packet and route said desired data packet onto a local area network connected to both said desired destination router and a computer having said desired destination address.

23. A method of routing a data packet addressed to a destination address, comprising:

receiving said data packet by a source router;

determining, by said source router, that said data packet is to be encapsulated as an encapsulated packet, and said encapsulated packet routed by a peer-to-peer protocol to a destination router;

interrogating a database, said database maintained on a server, said database having entries for destination addresses, an entry for a particular destination addresses giving the address of a router capable of routing a packet to said particular destination addresses;

addressing, in response to information received from said database connecting said destination address with said destination router, said encapsulated packet to said destination router; and

,

transmitting said encapsulated packet onto a connectionless network for transmission to said destination router.

24. A source router to route a data packet addressed to a destination address, comprising:

means for receiving said data packet by said source router;

means for determining, by said source router, that said data packet is to be encapsulated as an encapsulated packet, and said encapsulated packet routed by a peer-to-peer protocol to a destination router;

means for interrogating a database, said database maintained on a server, said database having entries for destination addresses, an entry for a particular destination addresses giving the address of a router capable of routing a packet to said particular destination addresses;

means for addressing, in response to information received from said database connecting said destination address with said destination router, said encapsulated packet to said destination router; and

,

means for transmitting said encapsulated packet onto a connectionless network for transmission to said destination router.

25. A source router to route a data packet addressed to a destination address, comprising:

a receiver to receive said data packet by said source router;

a packet parsing circuit to determine, by said source router, that said data packet is to be encapsulated as an encapsulated packet, and said encapsulated packet routed by a peer-to-peer protocol to a destination router;

a cpu and a transmit circuit, to interrogate a database, said database maintained on a server, said database having entries for destination addresses, an entry for a particular destination addresses giving the address of a router capable of routing a packet to said particular destination addresses;

a cpu and a transmit circuit to address, in response to information received from said database connecting said destination address with said destination router, said encapsulated packet to said destination router; and

,

a transmitting circuit to transmit said encapsulated packet onto a connectionless network for transmission to said destination router.