Nortel 1000BASE-LX, Using Manual, Page: 55 / 214

Chapter 2 Network configuration 55
Using the BayStack 420 10/100/1000 Switch
Figure 11 Port-based VLAN example
IEEE 802.1Q tagging
BayStack 420 switches operate in accordance with the IEEE 802.1Q tagging
rules. Important terms used with the 802.1Q tagging feature are:
• VLAN identifier (VID)—the 12-bit portion of the VLAN tag in the frame
header that identifies an explicit VLAN. When other types of VLANs are
enabled, this default value can be overridden by the values enabled in the
Web-based management interface. Refer to
Using Web-Based Management
for the BayStack 420 10/100/1000 Switch .
• Port VLAN identifier (PVID)—a classification mechanism that associates a
port with a specific VLAN. For example, a port with a PVID of 3 (PVID =3)
assigns all untagged frames received on this port to VLAN 3.
• Tagged frame— the 32-bit field (VLAN tag) in the frame header that
identifies the frame as belonging to a specific VLAN. Untagged frames are
marked (tagged) with this classification as they leave the switch through a
port that is configured as a tagged port.
• Untagged frame— a frame that does not carry any VLAN tagging information
in the frame header.
• VLAN port members— a set of ports that form a broadcast domain for a
specific VLAN. A port can be a member of one or more VLANs.
BayStack
420
VLAN 1 VLAN 2
10004EA