System analyzer and method for synchronizing a distributed system

• US 6,724,729 B1
• Filed: 12/30/1998
• Issued: 04/20/2004
• Est. Priority Date: 12/30/1998
• Status: Expired due to Term

• Current Assignee: Viavi Solutions, Inc. (Lumentum Holdings Inc.)
• Original Assignee: Finisar Corporation (II-VI Incorporated)
• Inventors: Sikdar, Som
• Primary Examiner(s): Yao, Kwang Bin
• Assistant Examiner(s): Harper, Kevin C.
• Application Number:
  US09/223,103
• Time in Patent Office: 1,938 Days
• Field of Search: 370/241, 370/250, 370/252, 370/253, 370/503, 370/389, 370/390, 370/498, 714/1, 714/37, 714/39, 714/712
• US Class Current: 370/241
• CPC Class Codes: H04L 41/00 Arrangements for maintenance, administration or management of data switching networks, e.g. of packet switching networks
• CPC Class Codes: H04L 43/106 using time related information in packets, e.g. by adding timestamps
• CPC Class Codes: H04L 43/18 Protocol analysers

Abstract

A method for synchronizing a distributed system is provided. The distributed system includes distributed analyzers. Each analyzer has a synchronization decoder circuit, a medium access controller, and a central processing unit. The distributed system synchronization method comprises receiving multicast information, generating local synchronization signals, receiving control data packets, and beginning processing of monitored data packets. The synchronization decoder circuit receives the multicast information, decodes the multicast information, and responsive to the multicast information, generates local synchronization signals. The decoder synchronization circuit of a first analyzer completes the decoding and the generating in a first time. The first time is adapted to enable the central processing unit of the first analyzer to start and end processing of monitored data packets at a first start time and a first end time. The first start time differs from a start time corresponding to any other analyzer by less than a maximum synchronization time. The first end time differs from an end time corresponding to any other analyzer by less than a maximum synchronization time. The maximum synchronization time comprises a parameter related to a smallest useful packet size and a network speed. The medium access controller receives control data packets. Each control data packet corresponds to a data stream. The monitored data packets are transmitted in a data stream selected for monitoring. Responsive to the local synchronization signals and the control data packets, the central processing unit for each analyzer processes monitored data packets.

Claims

1. A method for synchronizing a distributed system, the distributed system having synchronized analyzers, and data streams, the distributed system supporting multicast communications, the method comprising:

selected synchronized analyzers receiving the multicast information and communication packets, each selected synchronized analyzer having processing resources including a synchronization decoder circuit, and one or more packet capture, analysis and generation circuits, the multicast information including destination data corresponding to addresses of the selected synchronized analyzers;

the synchronization decoder circuit decoding the multicast information;

responsive to the multicast information, the synchronization decoder circuit generating local signals;

the synchronization decoder circuit transferring the local signals to the one or more selected packet capture, analysis and generation circuits, and

the synchronization decoder circuit of a first selected synchronized analyzer receives the multicast information at a first multicast receipt time (t₁), the selected synchronized analyzers adapted to ensure that the first multicast receipt time differs from the multicast receipt time corresponding to any other selected synchronized analyzer by no more than a maximum synchronization time, the maximum synchronization time comprises a parameter related to a smallest useful packet size and a network speed, and the maximum synchronization time is less than approximately one microsecond.

2. A method for synchronizing a distributed system, the distributed system having synchronized analyzers, and data streams, the distributed system supporting multicast communications, the method comprising:

selected synchronized analyzers receiving the multicast information and communication packets, each selected synchronized analyzer having processing resources including a synchronization decoder circuit, and one or more packet capture, analysis and generation circuits, the multicast information including destination data corresponding to addresses of the selected synchronized analyzers;

the synchronization decoder circuit decoding the multicast information;

responsive to the multicast information, the synchronization decoder circuit generating local signals;

the synchronization decoder circuit transferring the local signals to the one or more selected packet capture, analysis and generation circuits;

the decoding and generating local signals steps are accomplished in a decoder delay time, the variation of the decoder delay time between selected synchronized analyzers is less than approximately five percent of the decoder delay time; and

the selected packet capture, analysis and generation circuits of a first selected synchronized analyzer start processing the monitored data packets at a first start time, the first start time differs from a start time corresponding to any other selected synchronized analyzer by no more than a maximum synchronization time, the maximum synchronization time comprises a parameter related to a smallest useful packet size and a network speed, and the maximum synchronization time is less than approximately one microsecond.

3. A method for synchronizing a distributed system, the distributed system having synchronized analyzers, and data streams, the distributed system supporting multicast communications, the method comprising:

selected synchronized analyzers receiving the multicast information and communication packets, each selected synchronized analyzer having processing resources including a synchronization decoder circuit, and one or more packet capture, analysis and generation circuits, the multicast information including destination data corresponding to addresses of the selected synchronized analyzers;

the synchronization decoder circuit decoding the multicast information;

responsive to the multicast information, the synchronization decoder circuit generating local signals;

the synchronization decoder circuit transferring the local signals to the one or more selected packet capture, analysis and generation circuits;

the synchronization decoder circuit of a first selected synchronized analyzer receives the multicast information at a first multicast receipt time (t₁), the selected synchronized analyzers adapted to ensure that the first multicast receipt time differs from the multicast receipt time corresponding to any other selected synchronized analyzer by no more than a maximum synchronization time, the maximum synchronization time comprises a parameter related to a smallest useful packet size and a network speed, and the maximum synchronization time is less than approximately one microsecond; and

responsive to the multicast information and the communication packets, the selected packet capture, analysis and generation circuits completing a first process for a first set of monitored data packets, the completing for each selected synchronized analyzer occurring at an end time.

4. A method for synchronizing a distributed system, the distributed system having synchronized analyzers, and data streams, the distributed system supporting multicast communications, the method comprising:

selected synchronized analyzers receiving the multicast information and communication packets, each selected synchronized analyzer having processing resources including a synchronization decoder circuit, and one or more packet capture, analysis and generation circuits, the multicast information including destination data corresponding to addresses of the selected synchronized analyzers;

the synchronization decoder circuit decoding the multicast information;

responsive to the multicast information, the synchronization decoder circuit generating local signals;

the synchronization decoder circuit transferring the local signals to the one or more selected packet capture, analysis and generation circuits;

the data streams comprise transmitted data packets and include monitored data streams selected for analysis at one or more monitored analysis locations;

responsive to the local signals and the communication packets, the selected packet capture, analysis and generation circuits beginning processing of monitored data packets from monitored data streams at a start time;

responsive to the multicast information and the communication packets, the packet capture, analysis and generation circuits completing a first process for a first set of monitored data packets, the processing for each selected synchronized analyzer completing at a corresponding end time;

the decoding and generating of local signals are accomplished in a decoder delay time, the variation of the decoder delay time between synchronized analyzers is less than approximately five percent of the decoder delay time; and

the selected packet capture, analysis and generation circuits of the first synchronized analyzer completes processing of the monitored data packets at a first end time, the first end time differs from an end time corresponding to any other synchronized analyzer by no more than a maximum synchronization time, the maximum synchronization time comprises a parameter related to a smallest useful packet size and a network speed, and the maximum synchronization time is less than approximately one microsecond.

5. A synchronized analyzer for synchronizing a distributed system comprising:

a synchronization decoder circuit having processing resources adapted to;

receive and decode multicast information;

responsive to the multicast information, generate local signals; and

one or more packet capture, analysis and generation circuits having processing resources adapted to;

receive the local signals at signal receipt times; and

responsive to local signals addressed to one or more selected packet capture, analysis and generation circuits;

capture portions of monitored data packets at monitored data receipt times, the monitored data packets transmitted in monitored data streams, the monitored data streams disposed in the distribution system and selected for analysis;

process portions of the monitored data packets; and

a multiple monitored analysis location analyzers having a plurality of packet capture, analysis and generation circuits, the plurality of packet capture, analysis and generation circuits having processing resources adapted to capture monitored data packets from a plurality of monitored analysis locations.

6. A system for synchronizing a distributed system, comprising:

data streams comprising transmitted data packets;

a control unit having processing resources adapted to transmit multicast information;

synchronized analyzers including;

synchronization decoder circuits having processing resources adapted to;

receive and decode the multicast information;

responsive to the multicast information, generate local signals; and

one or more packet capture, analysis and generation circuits having processing resources adapted to;

receive the local signals at signal receipt times;

responsive to local signals addressed to one or more selected packet capture, analysis and generation circuits;

capture portions of monitored data packets from data streams selected for analysis at monitored data receipt times, and

process the portions of the monitored data packets, the processing of the portions of the monitored data packets adapted to analyze and manage the distributed system;

a first network link connecting the control unit to the synchronized analyzers and the synchronized analyzers to each other, the control unit processing resources transmit the multicast information to the synchronized analyzers through the first network link; and

wherein the synchronized analyzers include multiple monitored analysis location analyzers, each of the multiple monitored analysis location analyzers having a plurality of packet capture, analysis and generation circuits, the plurality of packet capture, analysis and generation circuits capturing monitored data packets from a plurality of monitored analysis locations.

7. A system for synchronizing a distributed system, comprising:

data streams comprising transmitted data packets;

a control unit having processing resources adapted to transmit multicast information;

synchronized analyzers including;

synchronization decoder circuits having processing resources adapted to;

receive and decode the multicast information;

responsive to the multicast information, generate local signals; and

one or more packet capture, analysis and generation circuits having processing resources adapted to;

receive the local signals at signal receipt times; and

responsive to local signals addressed to one or more selected packet capture, analysis and generation circuits;

capture portions of monitored data packets from data streams selected for analysis at monitored data receipt times, and

process the portions of the monitored data packets, the processing of the portions of the monitored data packets adapted to analyze and manage the distributed system;

a first network link connecting the control unit to the synchronized analyzers and the synchronized analyzers to each other, the control unit processing resources transmit the multicast information to the synchronized analyzers through the first network link; and

wherein the decoder synchronization circuit processing resources of a first synchronized analyzer receive the multicast information at a first multicast receipt time (t₁), the synchronized analyzers adapted to ensure that the first multicast receipt time differs from the multicast receipt time corresponding to any other synchronized analyzer in the distributed system by no more than a maximum synchronization time, the maximum synchronization time comprises a parameter related to a smallest useful packet size and a network speed, and the maximum synchronization time is less than approximately one microsecond.

8. A system for synchronizing a distributed system, comprising:

data streams comprising transmitted data packets;

a control unit having processing resources adapted to transmit multicast information;

synchronized analyzers including;

synchronization decoder circuits having processing resources adapted to;

receive and decode the multicast information;

responsive to the multicast information, generate local signals; and

one or more packet capture, analysis and generation circuits having processing resources adapted to;

receive the local signals at signal receipt times; and

responsive to local signals addressed to one or more selected packet capture, analysis and generation circuits;

capture portions of monitored data packets from data streams selected for analysis at monitored data receipt times, and

process the portions of the monitored data packets, the processing of the portions of the monitored data packets adapted to analyze and manage the distributed system;

a first network link connecting the control unit to the synchronized analyzers and the synchronized analyzers to each other, the control unit processing resources transmit the multicast information to the synchronized analyzers through the first network link; and

wherein the packet capture, analysis and generation circuit processing resources of a first synchronized analyzer start processing the monitored data packets at a first start time, the first start time differs from a start time corresponding to any other synchronized analyzer by no more than a maximum synchronization time, the maximum synchronization time comprises a parameter related to a smallest useful packet size and a network speed, and the maximum synchronization time is less than approximately one microsecond.

9. A system for synchronizing a distributed system, comprising:

data streams comprising transmitted data packets;

a control unit having processing resources adapted to transmit multicast information;

synchronized analyzers including;

synchronization decoder circuits having processing resources adapted to;

receive and decode the multicast information;

responsive to the multicast information, generate local signals; and

one or more packet capture, analysis and generation circuits having processing resources adapted to;

receive the local signals at signal receipt times; and

responsive to local signals addressed to one or more selected packet capture, analysis and generation circuits;

capture portions of monitored data packets from data streams selected for analysis at monitored data receipt times, and

process the portions of the monitored data packets, the processing of the portions of the monitored data packets adapted to analyze and manage the distributed system;

a first network link connecting the control unit to the synchronized analyzers and the synchronized analyzers to each other, the control unit processing resources transmit the multicast information to the synchronized analyzers through the first network link; and

wherein the decoder synchronization circuit processing resources of a first synchronized analyzer transfer the local signals to selected packet capture, analysis and generation circuits of the first synchronized analyzer at a first transfer time (t₃), the synchronized analyzers adapted to ensure that the first transfer time differs from the transfer time corresponding to any other synchronized analyzer in the distributed system by no more than a maximum synchronization time, the maximum synchronization time comprises a parameter related to a smallest useful packet size and a network speed, and the maximum synchronization time is less than approximately one microsecond.

10. A method for synchronizing a distributed system, the distributed system having synchronized analyzers, and data streams, the distributed system supporting multicast communications, the method comprising:

selected synchronized analyzers receiving the multicast information and communication packets, each selected synchronized analyzer having processing resources including a synchronization decoder circuit, and one or more packet capture, analysis and generation circuits, the multicast information including destination data corresponding to addresses of the selected synchronized analyzers;

the synchronization decoder circuit decoding the multicast information;

responsive to the multicast information, the synchronization decoder circuit generating local signals;

the synchronization decoder circuit transferring the local signals to the one or more selected packet capture, analysis and generation circuits;

the decoding and generating local signals steps are accomplished in a decoder delay time, the variation of the decoder delay time between selected synchronized analyzers is less than approximately five percent of the decoder delay time; and

the decoder synchronization circuit of a first selected synchronized analyzer transfers the local signals to the selected packet capture, analysis and generation circuits of the first synchronized analyzer at a first transfer time (t₃), the selected synchronized analyzers adapted to ensure that the first transfer time differs from the transfer time corresponding to any other of the selected synchronized analyzers by no more than a maximum synchronization time, the maximum synchronization time comprises a parameter related to a smallest useful packet size and a network speed, and the maximum synchronization time is less than approximately one microsecond.