Method of remote active testing of a device or network

• US 8,654,790 B2
• Filed: 05/13/2011
• Issued: 02/18/2014
• Est. Priority Date: 06/15/2010
• Status: Active Grant

• Current Assignee: Viavi Solutions, Inc. (Lumentum Holdings Inc.)
• Original Assignee: JDS Uniphase Corporation (Lumentum Holdings Inc.)
• Inventors: Haver, Joe, Hidai, Takashi, Bauer, Sam, Hsueh, Canning
• Primary Examiner(s): Chung, Hoon J
• Application Number:
  US13/107,752
• Publication Number:
  US 20110305150A1
• Time in Patent Office: 1,012 Days
• Field of Search: 370/389, 370/392, 370/394, 370/474, 370/521, 709/231, 709/236, 714/715
• US Class Current: 370/474
• CPC Class Codes: H04L 2212/00 Encapsulation of packets
• CPC Class Codes: H04L 43/022 by sampling
• CPC Class Codes: H04L 43/026 using flow identification
• CPC Class Codes: H04L 43/028 by filtering
• CPC Class Codes: H04L 43/062 related to network traffic
• CPC Class Codes: H04L 43/0829 Packet loss
• CPC Class Codes: H04L 43/106 using time related information in packets, e.g. by adding timestamps
• CPC Class Codes: H04L 43/12 Network monitoring probes
• CPC Class Codes: H04L 43/18 Protocol analysers
• CPC Class Codes: H04L 43/50 Testing arrangements

Abstract

A test device includes a packet input receiver for receiving encapsulated packets from a network; a packet reader for extracting timing information from the encapsulated packets, and for decapsulating encapsulated packets so as to obtain test packets; a FIFO queue for storing the test packets; a packet controller for reading the test packets from the FIFO queue and writing the test packets into a de-jitter buffer in accordance with the timing information, the de-jitter buffer for storing the reordered test packets; and, a packet output generator for providing the test packets to a target device wherein time intervals between the test packets are reproduced using the timing information.

Claims

1. A method of testing a communication device or network under test, comprising:

at a remote test system, generating portions of test packets separated by time intervals, encapsulating the portions of test packets thereby forming encapsulated packets, and adding timing information to the encapsulated packets so as to preserve the portions of the test packets and information related to the time intervals, wherein the encapsulated packets preserve headers of the portions of test packets;

transmitting the encapsulated packets over a transport network from the remote test system to a local test device;

at the local test device, decapsulating the encapsulated packets so as to obtain replay packets and

the timing information, wherein the replay packets include the portions of the test packets; and

, transmitting the replay packets separated by the time intervals from the local test device to the communication device or network under test,

wherein the timing information is used by the local test device to reproduce the time intervals so as to imitate a stream of the test packets generated at the remote test system.

2. The method as defined in claim 1 wherein the time intervals between the test packets are non-periodic intervals.

3. The method as defined in claim 1 wherein the portions of the test packets are encrypted within the encapsulated packets.

4. The method as defined in claim 1 wherein a destination address of the encapsulated packets is a network address of a downstream device that is downstream from the local test device with respect to the remote test system.

5. The method as defined in claim 1 wherein the local test device is an unaddressed device.

6. The method as defined in claim 1 wherein the local test device is one of a plurality of local test devices synchronized for testing the network under test.

7. The method as defined in claim 1 wherein the timing information comprises timestamps.

8. A method of testing a communication device or network under test, comprising:

at a local test device;

(i) receiving encapsulated packets from a remote test system via a transport network, wherein, prior to the receiving, the remote test system generates portions of test packets separated by time intervals, encapsulates the portions of test packets to form the encapsulated packets, and adds timing information to the encapsulated packets so as to preserve the portions of the test packets, information related to the time intervals, and headers of the portions of test packets,

(ii) extracting timing information from the encapsulated packets,

(iii) decapsulating the encapsulated packets so as to obtain the portions of test packets, and

(iv) forming replay packets, wherein the replay packets include the portions of the test packets; and

,

transmitting the replay packets from the local test device to the communication device or network under test,

wherein the replay packets are separated by the time intervals so as to imitate the test packets originated by the remote test system, and wherein the time intervals are reproduced at the local test device using the timing information.

9. The method as defined in claim 8 wherein the decapsulating of the encapsulated packets includes decryption.

10. The method as defined in claim 8 wherein reproduction of the time intervals includes de-jittering of the packets using a de-jitter buffer.

11. The method as defined in claim 10 wherein the reproduction of the time intervals includes sequencing of the replay packets based on sequence numbers of the encapsulated packets.

12. The method as defined in claim 8 wherein the network under test and the transport network are a same network.

13. The method as defined in claim 8 wherein the timing information comprises timestamps.

14. A test device comprising:

a packet input receiver for receiving encapsulated packets from a remote test system over a network, wherein, prior to the receiving, the remote test system generates portions of test packets separated by time intervals, encapsulates the portions of test packets to form the encapsulated packets, and adds timing information to the encapsulated packets so as to preserve the portions of the test packets, information related to the time intervals, and headers of the portions of test packets;

a packet reader for extracting the timing information from the encapsulated packets, for decapsulating the encapsulated packets so as to obtain the test packets, and for placing the test packets in a FIFO queue;

a packet controller for reading the test packets from the FIFO queue and writing the test packets into a de-jitter buffer in accordance with the timing information, a memory for the de jitter buffer for storing the reordered test packets; and

,

a packet output generator for providing the test packets to a target device wherein the time intervals between the test packets are reproduced using the timing information.