Propagation of signals between devices for triggering capture of network data

• US 20050060402A1
• Filed: 06/30/2004
• Published: 03/17/2005
• Est. Priority Date: 09/10/2002
• Status: Active Grant

• Current Assignee: Viavi Solutions, Inc. (Lumentum Holdings Inc.)
• Original Assignee: Viavi Solutions, Inc. (Lumentum Holdings Inc.)
• Inventors: Strong, Stephen, Oyadomari, Randy
• Granted Patent: US 8,266,271 B2
• Time in Patent Office: Days
• US Class Current: 709/224
• CPC Class Codes: H04L 43/026 using flow identification
• CPC Class Codes: H04L 43/18 Protocol analysers

Abstract

Protocol analyzers systems and methods coordinate the capture of network data of interest across multiple chassis. Each chassis has individual blades with accompanying ports and is serially connected to other chassis in the system. Selected ports from each chassis are configured in domains that can be spread across the serially connected chassis and used in coordination to capture network data of interest. A serial protocol containing control signals is used to transmit run, stop, and trigger data between the serially connected chassis and thereby coordinate the activity of ports within each domain. Through the use of the serial protocol the number of wires connecting adjacent chassis is minimized and each of the blades in the multi-chassis systems can be synchronously started, stopped, and triggered at the same time to synchronously capture the network data of interest.

Claims

1. In a protocol analyzer system in a computer network, a method for capturing network data of interest, the method comprising:

receiving communications traffic through a domain of ports on a protocol analyzer, wherein the domain of ports is distributed over a plurality of chassis;

monitoring the communications traffic through one or more analyzer modules to identify data of interest, each analyzer module being in communication with and receiving the communications traffic through at least one of the ports in the domain of ports; and

delivering one or more control signals between the plurality of chassis using a serial protocol, wherein the control signals coordinate the operation of each port in the domain of ports.

2. The method as in claim 1, wherein each chassis further comprises a field programmable gate array, each field programmable gate array capable of analyzing the serial protocol to identify which of the one or more control signals is directed to which ports located at its respective chassis.

3. The method as in claim 1, wherein at least one control signal comprises a trigger signal for propagation to each of the ports in the domain, wherein the trigger signal triggers a capture buffer in communication with each port in the domain to capture a selected portion of the communications traffic.

4. The method as in claim 3, wherein the trigger signal is generated at a port when selected network data of interest is identified or when selected characteristics of the communications are identified.

5. The method as in claim 1, wherein the control signals identify whether each port in the domain should be running or stopped and whether each port should trigger.

6. The method as in claim 3, wherein the capture buffer operates by storing a selected portion of the communications traffic, the capture buffer operating by writing the newly received communications traffic over the oldest communications traffic stored in the capture buffer, wherein the trigger signal directs the capture buffer to stop writing new data into the capture buffer at a specified time, thus preserving a selected portion of the communications traffic.

7. The method as in claim 6, wherein the trigger signal directs the capture buffer to capture a selected portion of the communications traffic by continuing to capture network data for a selected period of time after the trigger signal is received, thereby storing in the capture buffer data network data received through the port both before and after the network data of interest is identified.

8. The method as in claim 1, further comprising generating a clock signal in one of the chassis and propagating that signal to at least one additional chassis via cables that are in communication with each chassis.

9. The method as in claim 1, further comprising:

filtering the communications traffic to identify selected portions of the communications traffic that it is desired to store in a capture buffer; and

storing only the identified portions of the communications traffic in the capture buffer.

10. The method as in claim 9, wherein:

the trigger signal is generated at a port when the port'"'"'s associated capture buffer is full; and

the trigger signal is propagated to each port in the domain and acts to stop the capture of data capture buffer associated with each port in the domain.

11. The method as in claim 1, wherein the serial protocol comprises:

a start word which identifies the serial protocol;

a plurality of data bits which indicate whether the devices connected to a particular port should be running and/or triggering;

at least one separator bit for separating the data bits into groupings; and

one parity bit to indicate the end of the serial protocol.

12. In a multi-chassis protocol analyzer system in a computer network, a method for capturing network data of interest in coordination across the multiple chassis, the method comprising:

configuring a domain of ports located over one or more blades on one or more chassis, each port in the domain being in communication with a respective analyzer module and a respective capture buffer;

at each analyzer module, monitoring data transmitted via the communications network in order to identify network data of interest; and

in response to an analyzer module attached to one of the ports in the domain identifying the network data of interest, triggering each capture buffer in communication with each port in the domain to capture a desired portion of the data transmitted via the communications network.

13. The method as in claim 12, wherein each chassis further comprises a field programmable gate array, each field programmable gate array capable of analyzing a serial protocol that is communicated between the chassis to identify and direct control signals which coordinate the operation of each port in the domain of ports.

14. The method as in claim 12, wherein each capture buffer operates by storing a selected portion of the data transmitted via the communications network, the capture buffer operating by writing the newly received data transmitted via the communications network over the oldest data transmitted via the communications network stored in the capture buffer, wherein a trigger signal directs the capture buffer to stop writing new data into the capture buffer at a specified time, thus preserving a selected portion of the data transmitted via the communications network.

15. The method as in claim 14, wherein the trigger signal directs the capture buffer to capture a selected portion of the data transmitted via the communications network by continuing to capture network data for a selected period of time after the trigger signal is received, thereby storing in the capture buffer data network data received through the port both before and after the network data of interest is identified.

16. The method as in claim 12, further comprising:

filtering the communications traffic to identify selected portions of the communications traffic that it is desired to store in the capture buffer; and

storing only the identified portions of the communications traffic in the capture buffer.

17. The method as in claim 12, wherein:

the step of triggering each capture buffer is performed by generating a trigger signal at a port when the port'"'"'s associated capture buffer is full; and

the trigger signal is propagated to each port in the domain and acts to stop the capture of data in the capture buffer associated with each port in the domain.

18. The method as in claim 12, wherein the step of triggering each capture buffer is performed by generating a trigger signal at a port when selected network data of interest is identified or when selected characteristics of the communications are identified.

19. In a protocol analyzer system in a computer network, a method for capturing network data of interest, the method comprising:

providing a multi-chassis protocol analyzer system, each chassis comprising first and second cable receptacles for inter-chassis communications and housing at least one blade, each blade comprising at least one port for connecting to a computer network, each port further being in communication with both a capture buffer and an analyzer module;

configuring a plurality of the ports into a domain located over at least two of the chassis;

transmitting, through at least one of the first and second cable receptacles, a serial protocol containing a run signal to place the domain of ports in a run mode whereby;

communications traffic is received through the domain of ports; and

the communications traffic is monitored by the analyzer modules in communication with the domain of ports to identify data of interest; and

transmitting, through at least one of the first and second cable receptacles, a serial protocol containing a trigger signal for propagation to each of the ports in the domain, the trigger signal operable to trigger the capture buffer in communication with each port in the domain to capture a selected portion of the communications traffic.

20. A method as defined in claim 19, wherein the trigger signal is generated in response to an analyzer module detecting network data of interest or when selected characteristics of the communications traffic are identified.

21. A method as defined in claim 19, further comprising:

filtering the communications traffic in the analyzer module to identify selected portions of the communications traffic that it is desired to store in a capture buffer; and

storing only the identified portions of the communications traffic in the capture buffer.

22. A method as defined in claim 21, wherein the trigger signal is generated in response to a capture buffer being filled with the identified portions of the communications traffic.

23. The method as in claim 19, wherein each chassis further comprises a field programmable gate array, each field programmable gate array analyzing the serial protocol to identify which of the one or more control signals is directed to which ports located at its respective chassis.

24. A method as defined in claim 19, wherein the first and second cable receptacles comprise RJ-45 jacks.

25. A protocol analyzer system for identifying and capturing network data of interest, comprising:

a first chassis and a second chassis, each chassis comprising;

at least one blade, each blade comprising;

a capture buffer for capturing network data of interest;

an analyzer for monitoring network traffic, identifying network data of interest, and triggering the capture of the network data of interest in the capture buffer;

at least one port for receiving network traffic and routing it to the capture buffer and/or the analyzer, wherein the at least one port in the first chassis and the at least one port in the second chassis comprise a domain of ports; and

a field programmable gate array capable of analyzing a serial protocol, which comprises one or more control signals, communicated between the first chassis and the second chassis to identify which of one or more control signals in the serial protocol is applicable to the ports located on each chassis.

26. A system as defined in claim 25, wherein the analyzer comprises:

a filter component, wherein the filter component is operable to monitor the network traffic to identify data of interest and direct the storage of the data of interest in the capture buffer; and

a trigger component, wherein the trigger component is operable to direct each port in the domain to capture a selected portion of the network traffic when the trigger component detects selected data of interest.

27. A system as defined in claim 25, wherein the data of interest comprises statistical information relating to the network traffic.

28. A system as defined in claim 25, wherein the data of interest comprises statistical information relating to transactional events between components interconnected via a communications network.

29. A system as defined in claim 25, wherein the data captured by the capture buffer ce comprises data that was transmitted via a communications network both before and after the trigger condition was satisfied.

30. A system as defined in claim 25, wherein the first and second chassis are interconnected by one or more dedicated cables for transmitting inter-chassis control signals.