Basic Concepts In Mstp - HP 1910 User Manual

point-to-point link or an edge port, which directly connects to a user terminal rather than to another
device or a shared LAN segment.
Although RSTP supports rapid network convergence, it has the same drawback as STP—All bridges
within a LAN share the same spanning tree, so redundant links cannot be blocked based on VLAN, and
the packets of all VLANs are forwarded along the same spanning tree.
Features of MSTP
Developed based on IEEE 802.1s, MSTP overcomes the limitations of STP and RSTP. In addition to the
support for rapid network convergence, it also allows data flows of different VLANs to be forwarded
along separate paths, providing a better load sharing mechanism for redundant links.
MSTP delivers the following features:
MSTP supports mapping VLANs to MST instances (MSTIs) by means of a VLAN-to-MSTI mapping
•
table. MSTP can reduce communication overheads and resource usage by mapping multiple
VLANs to one MSTI.
MSTP divides a switched network into multiple regions, each containing multiple spanning trees
•
that are independent of one another.
MSTP prunes a loop network into a loop-free tree, avoiding proliferation and endless cycling of
•
packets in a loop network. In addition, it provides multiple redundant paths for data forwarding,
supporting load balancing of VLAN data.
• MSTP is compatible with STP and RSTP.

Basic concepts in MSTP

Figure 179 shows a switched network that comprises four MST regions, each MST region comprising four
MSTP devices. Figure 180 shows the networking topology of MST region 3.
151