Installation manual

Operation Manual - STP
Quidway S3000-EI Series Ethernet Switches Chapter 1
MSTP Region-configuration
Huawei Technologies Proprietary
1-4
1.1.2 MS
several MST regions and calculates and
are generated in a region and each of
, and others are called MSTI.
ted from the switches on the entire
PDUs. MSTP calculates and
connecting the regions. CIST is the
etwork.
ent MSTIs for different VLANs according
etween VLAN and the spanning tree. The calculation process of
MSTI is same like RSTP.
In this way, the packets of a VLAN travel along the corresponding MSTI inside the MST
T between different regions.
) to
decide the topology of the network. The configuration BPDU contains the information
e switches to compute the spanning tree.
er
onfiguration BPDU: MessageAge
z The maximum age of the configuration BPDU: MaxAge
witch and designated port?
TP Principles
MSTP divides the entire Layer 2 network into
generates CST for them. Multiple spanning trees
them is called an MSTI. The instance 0 is called IST
I. CIST calculation
The CIST root is the highest-priority switch elec
network through comparing their configuration B
generates IST in an MST region and also the CST
unique single spanning tree of the entire switching n
II. MSTI calculation
Inside an MST region, MSTP generates differ
to the association b
region and the CS
Followed introduce the calculation process of one MSTI.
The fundamental of STP is that the switches exchange a special kind of protocol packet
(which is called configuration Bridge Protocol Data Units, or BPDU, in IEEE 802.1D
enough to ensure th
The configuration BPDU mainly contains the following information:
z The root ID consisting of root priority and MAC address
z The cost of the shortest path to the root
z Designated switch ID consisting of designated switch priority and MAC address
z Designated port ID consisting of port priority and port numb
z The age of the c
z Configuration BPDU interval: HelloTime
z Forward delay of the port: ForwardDelay.
What are the designated s