US 7,460,542 B2 · Tagging rules for hybrid ports

Abstract

A VLAN tagging method employed in a data communications switching device is disclosed. VLAN tagging is processed in accordance with one of a plurality of VLAN tagging modes, namely, a fixed port mode, a tagged port mode, a protocol-enforced port mode, a protocol-enforced port mode, and a standards-observant mode. The fixed port mode applies a VLAN tag with a default VLAN identifier associated with the ingress port. The tagged port mode preserves the tag received with the packet, or appends a new tag with a default VLAN identifier if the incoming VLAN tag is not present. In the protocol-enforced port mode, the VLAN identifier is selected based on the protocol type of the received PDU. In the standards-observant mode, an incoming VLAN tag is retained if present, or a new tag selected based on the protocol type of the received PDU if the received packet is untagged.

Claims8

Dependent claims

A virtual local area network (VLAN) tagging method in a data communications switching device, the method comprising the steps of:

receiving a protocol data unit (PDU) on a port with the port operable in at least 1 of at least 3 VLAN tagging modes;
determining the VLAN tagging mode associated with the port;
and
if the determination is made that the port is operating in a first of the at least 3 VLAN tagging modes, then determining a default VLAN identifier associated with the port;
if the determination is made that the port is operating in a second of the at least 3 VLAN tagging modes, then:
determining if the received PDU comprises an incoming VLAN tag,
if the incoming VLAN tag is present, then determining the VLAN identifier of the VLAN tag, and
if the VLAN tag is not present, then determining the default VLAN identifier associated with the port;
and
if the determination is made that the port is operating in a third of the at least 3 VLAN tagging modes, then determining a protocol-dependent VLAN identifier associated with the protocol type of the received PDU.

7 more elements

Dependencies are inferred from the claim text.

Tagging rules for hybrid ports

Life of this patent

Tagging rules for hybrid ports

Life of this patent

Abstract

Claims8