Enterasys 6000 User Guide
VLAN Terms
VLAN Operation and Network Applications
13-5
13.4 VLAN TERMS
To fully understand the operation and configuration of port based VLANs, it is essential to
understand the definitions of several key terms.
understand the definitions of several key terms.
Table 13-1
VLAN Terms and Definitions
VLAN Term
Definition
VLAN ID
A unique number (between 1 and 4094) that identifies a
particular VLAN. Up to 1000 VLANs can be created on one
SmartSwitch.
particular VLAN. Up to 1000 VLANs can be created on one
SmartSwitch.
VLAN Name
A 32-character alphanumeric name associated with a VLAN ID.
The VLAN Name is intended to make user-defined VLANs
easier to identify and remember.
The VLAN Name is intended to make user-defined VLANs
easier to identify and remember.
Egress
Output direction of data from a network device.
Ingress
Incoming direction of data to a network device.
Filtering Database
Identifier (FDB ID)
Identifier (FDB ID)
Addressing information that the device learns about a VLAN is
stored in the filtering database assigned to that VLAN. Several
VLANs can be assigned to the same FDB ID to allow those
VLANs to share addressing information. This enables the devices
in the different VLANs to communicate with each other when the
individual ports have been configured to allow communication to
occur.
stored in the filtering database assigned to that VLAN. Several
VLANs can be assigned to the same FDB ID to allow those
VLANs to share addressing information. This enables the devices
in the different VLANs to communicate with each other when the
individual ports have been configured to allow communication to
occur.
The configuration is accomplished using the Local Management
VLAN Forwarding Configuration screen. By default a VLAN is
assigned to the FDB ID that matches its VLAN ID.
VLAN Forwarding Configuration screen. By default a VLAN is
assigned to the FDB ID that matches its VLAN ID.
Tag Header (VLAN Tag)
Four bytes of data inserted in a frame that identifies the
VLAN/frame classification. The Tag Header is inserted into the
frame directly after the Source MAC address field. Twelve bits of
the Tag Header represent the VLAN ID. The remaining bits are
other control information.
VLAN/frame classification. The Tag Header is inserted into the
frame directly after the Source MAC address field. Twelve bits of
the Tag Header represent the VLAN ID. The remaining bits are
other control information.
Tagged Frame
A data frame that contains a Tag Header. A VLAN-aware device
can add the Tag Header to any frame it transmits.
can add the Tag Header to any frame it transmits.
Untagged Frame
A data frame that does not have a Tag Header.