Brocade BigIron RX Series Configuration Guide - Manual (Page 432)

354 BigIron RX Series Configuration Guide
53-1002484-04
SuperSpan™
12
Customer uses single STP but SP uses multiple spanning trees
Figure 38 shows an example of SuperSpan where the customer network uses Single STP while the
SP uses multiple spanning trees.
FIGURE 38 Customer using single STP and SP using Multiple Spanning Trees
In this setup, the customer network is running a single spanning tree for VLANs 10 and 20. The
traffic from VLAN 10 and 20 will be carried, or aggregated by VLAN 100 at the SP’s network. The
main difference between this scenario and the previous two scenarios is that all traffic at the
customer’s network now follows the same path, having the same STP root bridge in all VLANs.
Therefore, the customer network will not have the ability to maximize network utilization on all its
links. On the other hand, loop-free, non-blocking topology is still separately maintained by the
customer network’s single spanning tree and the SP’s per-VLAN spanning tree on VLAN 100.
Customer and SP use single STP
Figure 39 shows an example of SuperSpan where the customer network and SP both use Single
STP.
tagged to multiple vlan
stp-boundary
untagged to vlan 100 (Super Aggregated VLAN)
Customer
Region
Provider
Region
Root bridge for VLAN xx
1/1
2/1
2/2
3/1
2/1
2/2
R
100
R
200
R
R
xx
single
span