Niveo Professional NGSME16T2H - Manual (Page 116)

Chapter 3: Featuring Configuration – Web UI
Featuring Configuration – Web UI
NGSME16T2H User Manual | 116
Spanning Tree
The switch supports Multiple Spanning Tree Protocol (MSTP), Rapid Spanning Tree
Protocol (RSTP) and Legacy Spanning Tree Protocol (STP).
The STP and RSTP is combined and defined in IEEE 802.1D-2004, Rapid Spanning
Tree Protocol. The RSTP protocol is applied to single network domain no matter
how many VLANs in your network. In RSTP domain, one of the switch acts as the
Root Switch and block one of the link with highest path cost to avoid network loop.
There are maximum 23 level switches within one RSTP domain, the network size
may be limited.
Multiple Spanning Tree Protocol (MSTP) is a direct extension of RSTP. It can provide
an independent spanning tree for different VLANs. With the Spanning Tree and
VLAN mapping, each VLAN has its own root and blocking path, the STP region size
becomes lower, the convergence time of topology change becomes faster as well.
There are some important abbreviations as below.
Common Spanning Tree (CST): Common Spanning Tree (CST) interconnects all
adjacent MST regions and acts as a virtual bridge node for communications with
STP or RSTP nodes in the global network.
Common and Internal Spanning Tree (CIST): MSTP connects all bridges and LAN
segments with a single Common and Internal Spanning Tree (CIST). The CIST is
formed as a result of the running spanning tree algorithm between switches that
support the STP, RSTP, MSTP protocols.
MSTI: Multiple Spanning Tree Instance: One VLAN can be mapped to a MSTI.
Each instance has its own root switch, forwarding path, blocking path and table. An
MST Region may contain multiple MSTI.