802.1Q Mode On Els10-27Tx; Vlan Hybrid Ports (802.1Q Mode); Vlan Access Ports (802.1Q Mode) - Cabletron Systems SmartSTACK ELS10-27TX Supplement Manual

The 802.1Q VLANs spans multiple systems and could span the entire network.
Unlike Workgroups, VLANs are not limited within a particular unit. The
maximum number of VLANs supported in 802.1Q mode on ELS10-27TX is 32.

1.3 802.1Q MODE ON ELS10-27TX

The SmartSTACK Ethernet ELS10-27TX operates in two modes: 802.1D and
802.1Q. While operating in 802.1Q mode, ports can be configured to allow non-
802.1Q devices to operate in this environment.

1.3.1 VLAN Hybrid Ports (802.1Q Mode)

A VLAN Hybrid port is used to connect one or more VLAN-aware or VLAN-
unaware devices to the switch. Both tagged and untagged frames can be received
and transmitted on Hybrid ports.
If a port on the ELS10-27TX is not configured as an Access port, it is a Hybrid
port.

1.3.2 VLAN Access Ports (802.1Q Mode)

The VLAN feature must be used only when non-802.1Q devices are attached to
this port. These ports are known as access ports.
An access command is a sub-command of the port command. An access port is
used to allow each segment to have multiple tag-unaware devices on it, and to
have those devices communicating on multiple VLANs.
An access port has three major characteristics:
1. When a packet is received, it will always insert a tag into the packet.
Tag-aware devices should not exist on a segment
NOTE
connected to an access port.
2. When a port transmits a packet, it always strips off the tag, even if it does
not match the default VLAN ID for that port.
3. Additional entries must be placed into the database to support it. When
addresses are learned on access ports, additional MAC addresses/VLAN ID
pairs are placed into the database to avoid flooding and to establish
connectivity.
For further information on Access Ports, refer to Appendix A, Virtual LANs
(VLANs).
Introduction
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