Protocol to coordinate network end points to measure network latency

• US 6,662,223 B1
• Filed: 07/01/1999
• Issued: 12/09/2003
• Est. Priority Date: 07/01/1999
• Status: Expired due to Term

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Raparla, Satyanarayana R., Zhang, Kui, Lautmann, John
• Primary Examiner(s): Alam, Hosain T.
• Assistant Examiner(s): Tran, Philip B.
• Application Number:
  US09/346,080
• Time in Patent Office: 1,622 Days
• Field of Search: 709/203, 709/223-224, 709/238, 709/240, 709/229, 370/230-233
• US Class Current: 709/224
• CPC Class Codes: H04L 41/0213 Standardised network management protocols, e.g. simple network management protocol [SNMP]
• CPC Class Codes: H04L 41/5003 Managing SLA; Interaction between SLA and QoS
• CPC Class Codes: H04L 41/5009 Determining service level performance parameters or violations of service level contracts, e.g. violations of agreed response time or mean time between failures [MTBF]
• CPC Class Codes: H04L 43/0829 Packet loss
• CPC Class Codes: H04L 43/087 Jitter
• CPC Class Codes: H04L 69/16 Implementation or adaptation of Internet protocol [IP], of transmission control protocol [TCP] or of user datagram protocol [UDP]
• CPC Class Codes: H04L 69/28 Timers or timing mechanisms used in protocols

Abstract

The invention provides a control mechanism that enables a destination router to authenticate response time requests issued by a source router before providing the requests to service software for processing. The control mechanism comprises a Network Endpoint Control Protocol (NECP) message format that is exchanged between the source and destination routers when measuring response time throughout the network. The NECP message format encapsulates a Command Length Status Data (CLSD) message that actually holds the response time requests. A collector router issues a novel control message to a responder router over a default responder port. If the responder is enabled for encryption communication, it will decrypt the control message according to the specified key and algorithm. If the responder is not so configured, it will check a conventional ACL to determine whether the client is authorized to communicate with the server. If permitted, the responder then responds to the collector in a manner dependent upon the particular protocol. In the case of a request to enable a UDP port for a particular time period, the responder processes a request and then sends back an acknowledgment to the collector. The collector receives the acknowledgment and then sends out a UDP probe packet to the responder. The responder then “echoes” the packet back to the collector, which keeps the result.

Claims

1. A method for authenticating response time requests issued from a source router by a destination router comprising the steps of:

receiving, at a default responder port of the destination router, a control protocol message sent by the source router, the message comprising a Network Endpoint Connection Protocol (NECP) message encapsulating a Command Length Status Data (CLSD) message therein, and when the NECP message is unencrypted, accessing an Access Control List (ACL) to determine whether a specified client is authorized, based upon information in the ACL, to utilize the default responder port, and in response to receipt of the CLSD message, initiating, at the destination router, a listening process at a predetermined port thereon, the listening process including enabling a User Datagram Protocol (UDP) server process at the predetermined port;

establishing a time limit for receiving a server request at the predetermined port at which time the predetermined port is enabled; and

receiving the server request at the predetermined port when the server request is received while the predetermined port is enabled.

2. The method as set forth in claim 1 wherein the step of establishing includes instructing, from a client, in communication with the destination router, the time interval within which the UDP server process is active.

3. The method as set forth in claim 1 wherein the step of transmitting the NECP message includes transmitting an encrypted NECP message and decrypting the encrypted NECP message at the destination router.

4. The method as set forth in claim 3 wherein the step of decrypting includes accessing a decryption key provided based upon an encryption enabler associated with the destination router.

5. The method as set forth in claim 1 wherein the step of initiating the listening process includes accepting Transmission Control Protocol (TCP)-format message at the predetermined port, the predetermined port being adapted to accept a TCP-format message thereat.

6. A method for authenticating response time requests issued from a source router by a destination router comprising the steps of:

receiving, at a default responder port of the destination router, a control protocol message sent by the source router, the message comprising an encrypted Network Endpoint Connection Protocol (NECP) message encapsulating a Command Length Status Data (CLSD) message therein, the NECP message having an MD5 format hashing checksum procedure, and in response to receipt of the CLSD message, decrypting, at the destination router, the encrypted NECP message by applying an MD5 format verification procedure to the message, and initiating, at the destination router, a listening process at a predetermined port thereon, the listening process including enabling a User Datagram Protocol (UDP) server process at the predetermined port;

establishing a time limit for receiving a server request at the predetermined port at which time the predetermined port is enabled; and

receiving the server request at the predetermined port when the server request is received while the predetermined port is enabled.

7. A network router that authenticates a received response time request issued from a source as a control protocol message, the message comprising a Network Endpoint Connection Protocol (NECP) message encapsulating a Command Length Status Data (CLSD) message therein, comprising:

a default responder port of the router that receives the control protocol message and, in response thereto, initiates, at the destination router, a listening process at a predetermined port on the router arranged to execute a User Datagram Protocol (UDP) server process;

a timer that establishes a time limit for receiving a server request at the predetermined port at which time the predetermined port is enabled;

means for receiving the server request at the predetermined port when the server request is received while the predetermined port is enabled; and

means for accessing an Access Control List (ACL), when the NECP message is unencrypted, to determine whether a specified client is authorized, based upon information in the ACL, to utilize the default responder port.

8. The router as set forth in claim 7 further comprising a client, in communication with the, for instructing the time interval within which the UDP server process is active.

9. The router as set forth in claim 8 wherein the control protocol message comprises an encrypted NECP message.

10. The router as set forth in claim 9 further comprising a decryption key provided to the router for decrypting the NECP message based upon an encryption enabler associated with the destination router.

11. The router as set forth in claim 7 wherein the default responder port is constructed and arranged to accept a Transmission Control Protocol (TCP)-format message at the predetermined port.

12. A network router that authenticates a received response time request issued from a source as a control protocol message, the message comprising an encrypted Network Endpoint Connection Protocol (NECP) message encapsulating a Command Length Status Data (CLSD) message therein, comprising:

a default responder port of the router that receives the control protocol message and, in response thereto, initiates, at the destination router, a listening process at a predetermined port on the router arranged to execute a User Datagram Protocol (UDP) server process;

a decryption key provided to the router for decrypting the NECP message based upon an encryption enabler associated with the destination router;

a timer that establishes a time limit for receiving a server request at the predetermined port at which time the predetermined port is enabled; and

means for receiving the server request at the predetermined port when the server request is received while the predetermined port is enabled.

13. The router as set forth in claim 12 further comprising a client, in communication with the, for instructing the time interval within which the UDP server process is active.

14. The router as set forth in claim 13 wherein the control protocol message comprises an encrypted NECP message.

15. The router as set forth in claim 14 further comprising a decryption key provided to the router for decrypting the NECP message based upon an encryption enabler associated with the destination router.

16. The router as set forth in claim 12 wherein the default responder port is constructed and arranged to accept a Transmission Control Protocol (TCP)-format message at the predetermined port.

17. A computer readable medium containing program instructions for:

receiving, at a default responder port of a router, a control protocol message, the message comprising a Network Endpoint Connection Protocol (NECP) message encapsulating a Command Length Status Data (CLSD) message therein, and in response thereto, initiating, at the router, a listening process at a predetermined port thereon, the listening process including enabling a User Datagram Protocol (UDP) server process at the predetermined port;

establishing a time limit for receiving a server request at the predetermined port at which time the predetermined port is enabled;

receiving the server request at the predetermined port when the server request is received while the predetermined port is enabled; and

accessing an Access Control List (ACL) when the NECP message is unencrypted to determine whether a specified client is authorized, based upon information in the ACL, to utilize the default responder port.

18. The computer readable medium as set forth in claim 17 wherein the instruction for establishing includes instructing, from a client, in communication with the router, the time interval within which the UDP server process is active.

19. The computer readable medium as set forth in claim 17 wherein the instruction for transmitting the NECP message includes transmitting an encrypted NECP message and decrypting the encrypted NECP message at the destination router.

20. The computer readable medium as set forth in claim 19 wherein the instruction for decrypting includes accessing a decryption key provided based upon an encryption enabler associated with the router.

21. A computer readable medium containing program instructions for:

receiving, at a default responder port of a router, a control protocol message, the message comprising an encrypted Network Endpoint Connection Protocol (NECP) message encapsulating a Command Length Status Data (CLSD) message therein, the NECP message having an MD5 format hashing checksum procedure, and in response thereto, decrypting, at the router, the encrypted NECP message by applying an MD5 format verification procedure to the message, and initiating, at the router, a listening process at a predetermined port thereon, the listening process including enabling a User Datagram Protocol (UDP) server process at the predetermined port;

establishing a time limit for receiving a server request at the predetermined port at which time the predetermined port is enabled; and

receiving the server request at the predetermined port when the server request is received while the predetermined port is enabled.

22. The computer readable medium as set forth in claim 21 wherein the instruction for establishing includes instructing, from a client, in communication with the router, the time interval within which the UDP server process is active.

23. The computer readable medium as set forth in claim 22 wherein the instruction for transmitting the NECP message includes transmitting an encrypted NECP message and decrypting the encrypted NECP message at the destination router.

24. The computer readable medium as set forth in claim 23 wherein the instruction for decrypting includes accessing a decryption key provided based upon an encryption enabler associated with the router.

25. Computer readable media, comprising:

said computer readable media containing instructions for execution in a processor for the practice of the method,

receiving, at a default responder port of the destination router, a control protocol message sent by the source router, the message comprising a Network Endpoint Connection Protocol (NECP) message encapsulating a Command Length Status Data (CLSD) message therein, and when the NECP message is unencrypted, accessing an Access Control List (ACL) to determine whether a specified client is authorized, based upon information in the ACL, to utilize the default responder port, and in response to receipt of the CLSD message, initiating, at the destination router, a listening process at a predetermined port thereon, the listening process including enabling a User Datagram Protocol (UDP) server process at the predetermined port;

establishing a time limit for receiving a server request at the predetermined port at which time the predetermined port is enabled; and

receiving the server request at the predetermined port when the server request is received while the predetermined port is enabled.

26. Electromagnetic signals propagating on a computer network, comprising:

said electromagnetic signals carrying instructions for execution on a processor for the practice of the method,

receiving, at a default responder port of the destination router, a control protocol message sent by the source router, the message comprising a Network Endpoint Connection Protocol (NECP) message encapsulating a Command Length Status Data (CLSD) message therein, and when the NECP message is unencrypted, accessing an Access Control List (ACL) to determine whether a specified client is authorized, based upon information in the ACL, to utilize the default responder port, and in response to receipt of the CLSD message, initiating, at the destination router, a listening process at a predetermined port thereon, the listening process including enabling a User Datagram Protocol (UDP) server process at the predetermined port;

establishing a time limit for receiving a server request at the predetermined port at which time the predetermined port is enabled; and

receiving the server request at the predetermined port when the server request is received while the predetermined port is enabled.

27. Computer readable media, comprising:

said computer readable media containing instructions for execution in a processor for the practice of the method,

receiving, at a default responder port of the destination router, a control protocol message sent by the source router, the message comprising an encrypted Network Endpoint Connection Protocol (NECP) message encapsulating a Command Length Status Data (CLSD) message therein, the NECP message having an MD5 format hashing checksum procedure, and in response to receipt of the CLSD message, decrypting, at the destination router, the encrypted NECP message by applying an MD5 format verification procedure to the message, and initiating, at the destination router, a listening process at a predetermined port thereon, the listening process including enabling a User Datagram Protocol (UDP) server process at the predetermined port;

establishing a time limit for receiving a server request at the predetermined port at which time the predetermined port is enabled; and

receiving the server request at the predetermined port when the server request is received while the predetermined port is enabled.

28. Electromagnetic signals propagating on a computer network, comprising:

said electromagnetic signals carrying instructions for execution on a processor for the practice of the method,

receiving, at a default responder port of the destination router, a control protocol message sent by the source router, the message comprising an encrypted Network Endpoint Connection Protocol (NECP) message encapsulating a Command Length Status Data (CLSD) message therein, the NECP message having an MD5 format hashing checksum procedure, and in response to receipt of the CLSD message, decrypting, at the destination router, the encrypted NECP message by applying an MD5 format verification procedure to the message, and initiating, at the destination router, a listening process at a predetermined port thereon, the listening process including enabling a User Datagram Protocol (UDP) server process at the predetermined port;

establishing a time limit for receiving a server request at the predetermined port at which time the predetermined port is enabled; and

receiving the server request at the predetermined port when the server request is received while the predetermined port is enabled.