Asymmetric packet switch and a method of use
The present invention relates to a packet switch and a packet switching method. An example embodiment of the present invention comprises at least three network ports, at least one instrument port, a mux-switch, a packet switch fabric, and an address table. The embodiment updates the address table to include the source address of each ingress packet of each network port and associate the source address with that network port. The mux-switch routes the ingress packet traffic of each network port according to the identity of the network port so that at least a copy of the packet traffic of one of the network ports is routed to an instrument port. The packet switch fabric routes the packets from the instrument ports to the network ports according the destination address of the packet and the identity of the network port that is associated with the destination address as recorded in the address table.
1. A packet switch configured to be connected to a packet-switching network and a network instrument, the packet switch comprising:
a plurality of ports comprising a first port, a second port, and a third port, wherein the first port is configured as a first network port to be connected to the packet-switching network;
a plurality of filters, wherein one of the filters is associated with one of the ports, and wherein the filters only filter packets entering through the ports; and
a computer-readable medium containing computer-executable instructions to operate the packet switch, comprising instructions to:
configure the second port to operate as a first instrument port to be connected to a network instrument;
establish a logical connection between the first network port and the first instrument port;
forward packets received from the packet-switching network through the first network port to the first instrument port;
after the packets are forwarded from the first network port, filter the packets using one of the filters before sending the packets out the first instrument port; and
configure the third port on the packet switch to operate as a first loop-back port, wherein a packet sent out the first loop-back port is looped back in through the first loop-back port, wherein the logical connection established between the first network port and the first instrument port includes a logical connection established from the first network port to the first loop-back port, and a logical connection established from the first loop-back port to the first instrument port, and wherein the packets forwarded from the first network port are forwarded from the first network port to the first loop-back port, and are forwarded from the first loop-back port to the first instrument port; and
establish a first filtering criterion for a first filter associated with the first loop-back port, wherein the packets are filtered by filtering the packets using the first filter associated with the first loop-back port based on the first established filtering criterion before the received packets are forwarded from the first loop-back port to the first instrument port.
2. The packet switch of claim 1 , wherein the logical connection established from the first network port to the first loop-back port includes a first virtual local area network having a membership of only the first network port and the first loop-back port, and wherein the logical connection established from the first loop-back port to the first instrument port includes a second virtual local area network having a membership of only the first loop-back port and the first instrument port.
3. The packet switch of claim 2 , further comprising instructions to:
when a packet egresses from the first loop-back port:
remove from the packet a first virtual local area network tag associated with the first virtual local area network; and
add to the packet a second virtual local area network tag associated with the second virtual local area network.
4. The packet switch of claim 1 , further comprising instructions to:
configure a fourth port on the packet switch to operate as a second instrument port connected to another network instrument, the fourth port being one of the plurality of ports;
configure a fifth port on the packet switch to operate as a second loop-back port, the fifth port being one of the plurality of ports, wherein a packet sent out the second loop-back port is looped back in through the second loop-back port;
establish a logical connection between the first network port and the second loop-back port;
establish a logical connection between the second loop-back port and the second instrument port;
establish a second filtering criterion for a second filter associated with the second loop-back port;
forward packets received from the packet-switching network through the first network port to the second loop-back port;
filter the packets using the second filter associated with the second loop-back port based on the second established filtering criterion; and
forward the filtered packets to the second instrument port.
5. The packet switch of claim 4 , wherein the logical connection established from the first network port to the first and second loop-back ports includes a first virtual local area network having a membership of only the first network port and the first and second loop-back ports, and wherein the logical connection established from the second loop-back port to the second instrument port includes a second virtual local area network having a membership of only the second loop-back port and the second instrument port.
6. The packet switch of claim 1 , wherein the packets are filtered based on occurrence of a predetermined event.
7. The packet switch of claim 6 , wherein the predetermined event includes a user-defined threshold value for bandwidth utilization.
8. A non-transitory computer-readable medium containing computer-executable instructions to operate a packet switch configured to be connected to a packet-switching network and a network instrument, wherein the packet switch includes a plurality of ports and a plurality of filters, the plurality of ports having a first port, a second port, and a third port, wherein the first port is configured as a network port to be connected to the packet-switching network, comprising instructions to:
configure the second port to operate as a first instrument port to be connected to the network instrument;
establish a logical connection between the network port and the first instrument port;
forward packets received from the packet-switching network through the network port to the first instrument port;
after the packets are forwarded from the network port, filter the packets using one of the filters before sending the packets out the first instrument port;
configure the third port on the packet switch to operate as a first loop-back port, wherein a packet sent out the first loop-back port is looped back in through the first loop-back port, wherein the logical connection established between the network port and the first instrument port includes a logical connection established from the network port to the first loop-back port, and a logical connection established from the first loop-back port to the first instrument port, and wherein the packets forwarded from the network port are forwarded from the network port to the first loop-back port, and are forwarded from the first loop-back port to the first instrument port; and
establish a first filtering criterion for a first filter associated with the first loop-back port, wherein the packets are filtered by filtering the packets using the first filter associated with the first loop-back port based on the first established filtering criterion before the received packets are forwarded from the first loop-back port to the first instrument port.
9. The non-transitory computer-readable medium of claim 8 , wherein the logical connection established from the network port to the first loop-back port includes a first virtual local area network having a membership of only the network port and the first loop-back port, and wherein the logical connection established from the first loop-back port to the first instrument port includes a second virtual local area network having a membership of only the first loop-back port and the first instrument port.
10. The non-transitory computer-readable medium of claim 9 , further comprising instructions to:
when a packet egresses from the first loop-back port:
remove from the packet a first virtual local area network tag associated with the first virtual local area network; and
add to the packet a second virtual local area network tag associated with the second virtual local area network.
11. The non-transitory computer-readable medium of claim 8 , further comprising instructions to:
configure a fourth port on the packet switch to operate as a second instrument port connected to another network instrument, the fourth port being one of the plurality of ports;
configure a fifth port on the packet switch to operate as a second loop-back port, the fifth port being one of the plurality of ports, wherein a packet sent out the second loop-back port is looped back in through the second loop-back port;
establish a logical connection between the network port and the second loop-back port;
establish a logical connection between the second loop-back port and the second instrument port;
establish a second filtering criterion for a second filter associated with the second loop-back port;
forward packets received from the packet-switching network through the network port to the second loop-back port;
filter the packets using the second filter associated with the second loop-back port based on the second established filtering criterion; and
forward the filtered packets to the second instrument port.
12. The non-transitory computer-readable medium of claim 11 , wherein the logical connection established from the network port to the first and second loop-back ports includes a first virtual local area network having a membership of only the network port and the first and second loop-back ports, and wherein the logical connection established from the second loop-back port to the second instrument port includes a second virtual local area network having a membership of only the second loop-back port and the second instrument port.
13. The non-transitory computer-readable medium of claim 8 , wherein the packets are filtered based on occurrence of a predetermined event.
14. The non-transitory computer-readable medium of claim 13 , wherein the predetermined event includes a user-defined threshold value for bandwidth utilization.