3Com 3CRWX120695A Reference Manual page 196

196 C 5: C
HAPTER ONFIGURING
WX S A
YSTEM AND DMINISTRATIVE
Moving a port or port group could potentially affect multiple VLANs.
To add a port or port group to the VLAN and retain previous VLAN
membership, click Add.
The port or port group now appears in the Current Members list.
4 To specify a tag value for a port or port group:
a Select the Tag checkbox for the port or port group.
By default, the checkbox is not selected. To remove a tag for a port or
port group, clear the checkbox.
b Double-click the Tag Value column for the port or port group.
c Change the tag value.
If you specify a tag value, 3Com recommends that you use the same
value as the VLAN number. 3Com WX switches do not require the VLAN
number and tag value to be the same, but some other devices do.
5 To add more ports or port groups to the VLAN, repeat step 2 through
step 4.
6 To remove a port or port group from the VLAN, select a port or port
group and click Remove. To make multiple selections, press Shift (for
contiguous items) or Control (for noncontiguous items) while clicking
items.
7 Do one of the following:
To configure Spanning Tree Protocol (STP), click Next to display the
Spanning Tree page. (See "Configuring Spanning Tree Protocol" on
page 196.)
To close the wizard and save the changes, click Finish.
Configuring Spanning Tree Protocol
The purpose of the Spanning Tree Protocol (STP) is to maintain a loop-free
network. A loop-free path is accomplished when a device recognizes a
loop in the topology and blocks one or more redundant paths.
Mobility System Software (MSS) supports 802.1D and Per-VLAN Spanning
Tree protocol (PVST+).
MSS uses 802.1D bridge protocol data units (BPDUs) on VLAN ports
that are untagged. However, each VLAN still runs its own instance of
STP, even if two or more VLANs contain untagged ports. To run a
single instance of STP in 802.1D mode on the entire switch, configure
all network ports as untagged members of the same VLAN.
P
ARAMETERS