Granted Patent B1

US 7,710,993 · App. 11/933,032 · Granted May 4, 2010

Assignee: Extreme Networks, Inc.

Abstract

Claims (32)

1. A computer-implemented method for pseudowire processing in a packet forwarding device, the method comprising:

determining whether an inbound port through which a packet has been transmitted to a packet forwarding device is a real port or a pseudowire port, wherein determining is performed in conjunction with inbound port information stored in at least one of a forwarding data base and an inbound label map of the packet forwarding device;

encoding the inbound port through which the packet is transmitted in a value of a first index having a predefined range of values representing real ports and pseudowire ports, the value based on whether the inbound port is determined to be the real port or the pseudowire port in conjunction with the stored inbound port information;

encoding an outbound port through which the packet will be transmitted in a value of a second index having a predefined range of values representing real ports and pseudowire ports; and

performing outbound packet processing for the packet in a switch fabric of the packet forwarding device based on determining, within their respective predefined range of values, where the first index value and the second index value fall, including:

determining whether the packet is transmitted through the packet forwarding device homogeneously, wherein the respective predefined ranges within which the first and second index values fall both represent real ports or both represent pseudowire ports, or heterogeneously, wherein the respective predefined ranges within which the first and second index values fall represent different types of ports, one representing a real port and the other representing a pseudowire port;

performing echo kill processing for packets transmitted homogenously; and

bypassing echo kill processing for packets transmitted heterogeneously.

2. The computer-implemented method of claim 1 , wherein the value of the second index having the range of values representing real ports and pseudowire ports further indicates whether the packet requires multicast processing or unicast processing, wherein multicast processing includes:

accessing a list of multicast entries corresponding to the value of the second index, the multicast entries being accessed via a multicast pointer and a copy counter; and

generating, for each entry in the list of multicast entries corresponding to the value of the second index, a new value for the second index; and

further performing outbound packet processing for the packet in the switch fabric of the packet forwarding device based on the new value of the second index, the new value of the second index falling within the predefined range of values for the second index representing real ports and pseudowire ports.

3. The computer-implemented method of claim 1 , further comprising:

mapping the value of the second index to a value of a third index, wherein values of the third index correspond to outbound port entries stored on the packet forwarding device, the entries for obtaining outbound port numbers;

accessing the outbound port entry to which the value of the third index corresponds; and

obtaining an outbound port number to be used when transmitting the packet to an outbound port based on the outbound port entry to which the value of the third index corresponds.

4. A packet-forwarding device for supporting pseudowire processing, the device comprising:

real ports;

pseudowire ports;

inbound port information stored on the packet forwarding device for determining whether an inbound packet is transmitted on one of the real ports or pseudowire ports;

outbound port information stored on the packet forwarding device for determining whether an outbound packet is transmitted on one of the real ports or the pseudowire ports; and

a processor in which to:

encode the inbound port information into an abstract port index having a predefined range of values representing the real ports and pseudowire ports;

encode the outbound port information into an egress port tag index having a predefined range of values representing the real ports and pseudowire ports;

perform outbound packet processing in accordance with the abstract port index and the egress port tag index, including:

performing echo kill processing of packets that are transmitted through the packet forwarding device homogenously, wherein the respective predefined ranges within which the abstract port and egress port tag index values fall both represent real ports or both represent pseudowire ports; and

bypassing echo kill processing of packets that are transmitted through the packet forwarding device heterogeneously, wherein the respective predefined ranges within which the abstract port and egress port tag index values fall represent different types of ports, one representing a real port and the other representing a pseudowire port.

5. The packet forwarding device of claim 4 , wherein the value of the egress port tag index having the range of values representing real ports and pseudowire ports further indicates whether the packet requires multicast processing or unicast processing, wherein the processor further:

accesses a list of multicast entries corresponding to the value of the egress port tag index,

the multicast entries being accessed via a multicast pointer and a copy counter; and

generates, for each entry in the list of multicast entries corresponding to the value of the egress port tag index, a new value for the egress port tag index; and

performs outbound packet processing based on the new value of the egress port tag index, the new value of the egress port tag index falling within the predefined range of values for the egress port tag index representing real ports and pseudowire ports.

Assignments (10)