Configuring MSTP
169
Chapter 23. Configuring MSTP
23.1 Brief Introduction to MSTP
The Spanning Tree Protocol (STP) was established based on the 802.1d standard of IEEE
to eliminate physical loops at the data link layer in a local area network (LAN). Devices
running this protocol detect loops in the network by exchanging information with one another
and eliminate loops by selectively blocking certain ports until the loop structure is pruned into
a loop-free network structure. This avoids proliferation and infinite recycling of packets that
would occur in a loop network and prevents deterioration of the packet processing capability
of network devices caused by duplicate packets received.
The multiple spanning tree protocol (MSTP) overcomes the shortcomings of STP and
RSTP. In addition to support for rapid network convergence, it also allows data flows of
different VLANs to be forwarded along their own paths, thus providing a better load sharing
mechanism for redundant links. For description about VLANs, refer to VLAN.
23.2 BPDU
MSTP uses BPDU algorithm the same as STP, RSTP. Meanwhile, BPDU in MSTP also
exist MSTP configuration information in the switch.
