Using the BayStack 450 10/100/1000 Series Switch
D-12 309978-D Rev 01
You can disable STP on the LEC VPorts with the risk of creating loops within the
network. If you are sure of a loop-free topology beyond the ATM uplink, then you
can disable the STP on the uplink ports to ensure connectivity on all four ELANs/
VLANs (
Figure D-6).
Figure D-6. LEC VPorts with Spanning Tree Disabled (2 of 2)
Note: Because there is only one BayStack 450-2M3/2S3 MDA LEC VPort on
one VLAN/ELAN, a loop-free network topology is ensured to some extent;
however, it may not be sufficient to ensure a loop-free topology for the entire
network.
PC1
PC2
BS45092A
BayStack 450
BayStack 450
450-2M3/2S3 MDA
LEC 2/ ELAN 2/ Vport 26
LEC 3/ ELAN 3/ Vport 27
LEC 1/ ELAN 1/ Vport 25
LEC 4/ ELAN 4/ Vport 28
450-2M3/2S3 MDA
Legend
Blocking
Forwarding
ATM Network
LEC 2/ ELAN 2/ Vport 26
LEC 3/ ELAN 3/ Vport 27
LEC 1/ ELAN 1/ Vport 25
LEC 4/ ELAN 4/ Vport 28