Cabletron Systems SmartSTACK ELS10-27TX Supplement Manual - 1.3.5  Switch Mode

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Introduction

1.3.5  Switch Mode

The unit operates in either an 802.1D or 802.1Q mode. The mode must be 

selected by the user and applies to all ports. The unit will not operate in a mixed 

mode. The default is to operate in 802.1D mode. 

For further information, refer to Switch Command in Chapter 2, Enhancements to 

LCM Commands.

1.3.6  Assigning Ports to a VLAN

A port becomes a member of a VLAN, by using the VLAN command. 

For further information, refer to the Port Command in Chapter 2, Enhancements 

to LCM Commands.

1.3.7  Default Port VLAN ID

If the unit is operating in 802.1Q mode, then each port will be configured with a 

default port VLAN ID (PVID). The default value for each port will be the default 

VLAN ID of 0x001. You are allowed to modify this on a per port basis.

When 802.1Q was developed, it was decided to configure a default VLAN ID for 

a port. If a packet is received on a port that does not have a VLAN ID or does not 

have a VLAN ID of zero, the default VLAN ID will be inserted. Once this tag is 

in place the packet is sent to the forwarding engine. Once the forwarding engine 

receives it, it will use this tag to determine which VLAN to restrict this packet to.

The sub-command of the port command known as the VLAN sub-command is 

used to set the default VLAN ID for the port. 

For further information, refer to Port Command in Chapter 2, Enhancements to 

LCM Commands.

NOTE

There is a sub-command of the port command known as the

VLAN sub-command. This is not used to make a port a member 

of the VLAN, and is not directly used in the forwarding and

filtering decision.