Users Guide
Figure 124. VLAN Stacking without L2PT
You might need to transport control trac transparently through the intermediate network to the other region. Layer 2 protocol
tunneling enables BPDUs to traverse the intermediate network by identifying frames with the Bridge Group Address, rewriting the
destination MAC to a user-congured non-reserved address, and forwarding the frames. Because the frames now use a unique MAC
address, BPDUs are treated as normal data frames by the switches in the intermediate network core. On egress edge of the
intermediate network, the MAC address rewritten to the original MAC address and forwarded to the opposing network region
(shown in the following illustration).
Dell Networking OS Behavior: In Dell networking OS version 9.1(1.0) and later, the L2PT MAC address is user-congurable, so you
can specify an address that non-Dell Networking systems can recognize and rewrite the address at egress edge.
Service Provider Bridging
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