Administrator's Guide v4.1.1 Manual

FIGURE 42 Multiple switch fabric configuration
Layer 2 forwarding
Layer 2 Ethernet frames are forwarded on the DCB ports. 802.1Q VLAN support is used to tag incoming
frames to specific VLANs, and 802.3ac VLAN tagging support is used to accept VLAN tagged frames
from external devices.
Network OS uses the following 802.1D bridging protocols between Layer 2 switches and to maintain a
loop-free network environment:
• Spanning Tree Protocol (STP)
• Rapid Spanning Tree Protocol (RSTP)
• Multiple Spanning Tree Protocol (MSTP)
• Per-VLAN Spanning Tree (PVST+)
• Rapid Per-VLAN Spanning Tree (RPVST+)
Layer 2 forwarding
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