Congestion notification in private VLANs
One embodiment of the present invention provides a switch. During operation, in a network with a private VLAN configuration, the switch allows a congestion notification message with an isolated virtual local area network identifier (VLAN ID) to be forwarded via an isolated VLAN port.
1. A switch, comprising:
a processor;
a computer-readable storage medium storing instructions which when executed by the processor causes the processor to perform a method, the method comprising:
allowing a frame with an isolated virtual local area network (VLAN) identifier to be forwarded via an isolated VLAN port; and
enforcing an egress VLAN filtering rule for the isolated VLAN port.
2. The switch of claim 1 , wherein the egress VLAN filtering rule permits forwarding of frames with an isolated VLAN identifier or primary VLAN identifier.
3. The switch of claim 1 , wherein the method further comprises enforcing an egress access control list.
4. The switch of claim 1 , wherein the method further comprises preventing a frame with an isolated VLAN identifier and which is not a congestion notification frame from being forwarded via the isolated VLAN port.
5. The switch of claim 3 , wherein the method further comprises examining an Ethertype field in the frame's header to determine whether the frame is a congestion notification message.
6. The switch of claim 1 , wherein the switch is an Ethernet switch.
7. A computer executable method, comprising:
allowing a frame with an isolated virtual local area network (VLAN) identifier to be forwarded via an isolated VLAN port; enforcing an egress VLAN filtering rule for the isolated VLAN port.
8. The method of claim 7 , wherein the egress VLAN filtering rule permits forwarding of frames with an isolated VLAN identifier or primary VLAN identifier.
9. The method of claim 7 , further comprising enforcing an egress access control list.
10. The method of claim 9 , wherein enforcing the egress access control list comprises preventing a frame with an isolated VLAN identifier and which is not a congestion notification frame from being forwarded via the isolated VLAN port.
11. The method of claim 9 , wherein enforcing the egress access control list comprises examining an Ethertype field in the frame's header to determine whether the frame is a congestion notification message.
12. The method of claim 7 , wherein the frame is an Ethernet frame.
13. A non-transitory computer-readable storage medium storing instructions which when executed by a computer cause the computer to perform a method, the method comprising:
allowing a frame with an isolated virtual local area network (VLAN) identifier to be forwarded via an isolated VLAN port; and
enforcing an egress VLAN filtering rule for the isolated VLAN port.
14. The non-transitory computer-readable storage medium of claim 13 , wherein the method further comprises enforcing an egress access control list.
15. The non-transitory computer-readable storage medium of claim 14 , wherein enforcing the egress access control list comprises preventing a frame with an isolated VLAN identifier and which is not a congestion notification frame from being forwarded via the isolated VLAN port.
16. The non-transitory computer-readable storage medium of claim 14 , wherein enforcing the egress access control list comprises examining an Ethertype field in the frame's header to determine whether the frame is a congestion notification message.
17. The non-transitory computer-readable storage medium of claim 13 , wherein the frame is an Ethernet frame.
18. The non-transitory computer-readable storage medium of claim 13 , wherein the egress VLAN filtering rule permits forwarding of frames with an isolated VLAN identifier or primary VLAN identifier.
19. A switch means, comprising:
a forwarding means for allowing a frame with an isolated virtual local area network (VLAN) identifier to be forwarded via an isolated VLAN port; and
an enforcing means for enforcing an egress VLAN filtering rule for the isolated VLAN port.