Network switch multiple-port sniffing

• US 7,027,437 B1
• Filed: 05/21/1999
• Issued: 04/11/2006
• Est. Priority Date: 05/21/1999
• Status: Expired due to Term

• Current Assignee: Advanced Micro Devices, Inc.
• Original Assignee: Advanced Micro Devices, Inc.
• Inventors: Williams, Robert, Merchant, Shashank
• Primary Examiner(s): Pham, Chi
• Assistant Examiner(s): LY, ANH VU H
• Application Number:
  US09/315,973
• Time in Patent Office: 2,517 Days
• Field of Search: 370/218, 370/250, 370/252, 370/299, 370/352, 370/353, 370/367, 370/368, 370/371, 370/386, 370/388, 370/395.7, 370/400, 370/422
• US Class Current: 370/389
• CPC Class Codes: H04L 43/12 Network monitoring probes
• CPC Class Codes: H04L 49/90 Buffering arrangements
• CPC Class Codes: H04L 49/901 using storage descriptor, e.g. read or write pointers

Abstract

A novel system and method of monitoring network activity in a network switching system having multiple ports for receiving and transmitting data packets, and a decision making engine for controlling data forwarding between the ports. Data blocks representing received data packets are placed in data queues corresponding to the receive ports. The data queues are transferred to logic circuitry for processing in accordance with a predetermined algorithm to determine destination information. At least one port for transmitting data packets is identified based on the destination information. In addition, a sniffer port selected among the plurality of ports is identified as a transmit port to provide output of data packets received or transmitted by multiple sniffed ports. A traffic capture mechanism that enables the sniffer port to output data transferred via multiple sniffed ports includes a sniffer port configuration circuit for selecting the sniffer port, and a sniffed port configuration circuit for selecting the multiple sniffed ports. The sniffer port configuration circuit may provide a signal to enable or disable monitoring of data traffic on the multiple sniffed ports.

Claims

1. A multiport data communication system for transferring data packets between ports, the data communication system comprising:

a plurality of ports for receiving and transmitting the data packets, and

a decision making engine responsive to received data packets for directing the received data packets to the ports selected for transmission of the received data packets,

the decision making engine including;

a forwarding circuit responsive to the received data packets for identifying at least one transmit port, and

a traffic capture mechanism for enabling one port of said plurality of ports to output data transferred via multiple other selected ports of said plurality of ports,

said traffic capture mechanism having a monitored port configuration circuit for selecting the multiple other ports among said plurality of ports, said monitored port configuration circuit is configured for storing a port vector having a plurality of port bits corresponding to said plurality of ports.

2. The system of claim 1, wherein said one port is a sniffer port for connecting to a probe for monitoring data traffic, and said multiple other selected ports are multiple sniffed ports monitored by the probe via the sniffer port.

3. The system of claim 2, wherein said traffic capture mechanism comprises a sniffer port configuration circuit for selecting the sniffer port among said plurality of ports.

4. The system of claim 3, wherein said sniffer port configuration circuit is configured to enable and disable monitoring of data traffic on the multiple sniffed ports.

5. The system of claim 1, wherein the port bits are set into predetermined states to select at least one of the multiple other ports.

6. The system of claim 1, wherein the forwarding circuit is configured to generate a forwarding descriptor identifying the ports for transmitting the data packets.

7. The system of claim 6, wherein the forwarding circuit is configured to include sniffer port data into the forwarding descriptor, if the port that received the data packet is one of the multiple other selected ports.

8. The system of claim 6, wherein the forwarding circuit is configured to determine whether destination information supplied to the forwarding circuit indicates that at least one of the multiple other selected ports is selected for transmission of a data packet.

9. The system of claim 8, wherein the forwarding circuit is configured to include sniffer port data into the forwarding descriptor, if at least one of the multiple other selected ports is selected for transmission of the data packet.

10. The system of claim 1, wherein said forwarding circuit is configured to determine whether a port that received a data packet is one of said multiple other selected ports.

11. The system of claims 1, wherein the decision making engine further comprises a plurality of queuing devices corresponding to the plurality of ports for queuing data blocks representing the data packets received by the corresponding ports, and logic circuitry responsive to the plurality of queuing devices for processing the data blocks in accordance with a prescribed algorithm to determine destination information.

12. In a communication network having a plurality of ports and a decision making engine for controlling data forwarding between the ports, a method of monitoring network activity, comprising the steps of:

placing data blocks representing received data packets in a plurality of data queues to be processed by the decision making engine,

processing the data queues by logic circuitry in accordance with a prescribed algorithm to determine destination information,

identifying at least one port for transmitting data packets based on the destination information,

selecting multiple sniffed ports among the plurality of ports for monitoring the data packets transferred via the sniffed ports, and

selecting a sniffer port among the plurality of ports to provide output of the data packets transferred via the sniffed ports,

wherein the step of selecting the sniffed ports comprises storing a sniffed port vector having a plurality of port bits corresponding to the plurality of ports.

13. The method of claim 12, wherein the sniffer port is identified as at least one of the ports for transmitting the data packet, if the port that received the data packet is one of the multiple sniffed ports.

14. The method of claim 12, wherein the step of identifying at least one port for transmitting data packets comprises determining whether the destination information indicates that at least one of the multiple sniffed ports is selected for transmitting a data packet.

15. The method of claim 14, wherein the sniffer port is identified as a port for transmitting the data packet, if at least one of the multiple sniffed ports is selected for transmitting the data packet.

16. The method of claim 12, wherein the step of identifying at least one port for transmitting data packets comprises determining whether a port that received a data packet is one of the multiple sniffed ports.

17. A multiport data communication system for transferring data packets between ports, the data communication system comprising:

a plurality of ports for receiving and transmitting the data packets,

a forwarding circuit responsive to received data packets for identifying at least one transmit port, and

a traffic capture mechanism for enabling one port of said plurality of ports to output data transferred via multiple other selected ports of said plurality of ports,

said forwarding circuit being configured to generate a forwarding descriptor identifying ports for transmitting the data packets, the forwarding descriptor including sniffer port data identifying said one port, if at least one of said multiple other selected ports is selected for transmitting a data packet.

18. The system of claim 17, wherein a port that received the data packet is one of the multiple other selected ports.