
Industrial Managed
Ethernet Switch
User Manual
錯誤
!
使用
[
常用
]
索
引標籤將
Heading
1,Product Manual
套用到您想要在此處
顯示的文字。
Page
100
of
191
Bri
.
Pri
.
)
Bridge
Priority
(
Bridge priority,
)
value
=
4096 × N,
)
N
:
0~15
(
32768
Bridge MAC
The MAC address of the switch which sent this BPDU
-
Note
:
1
.
In general, the path cost is dependent on the link speed
Table 2.37 lists the default values of path cost for STP
and RSTP
.
Table 2.37 Default Path Cost for STP and RSTP
Data Rate
STP Cost (802.1D-1998)
RSTP Cost (802.1W-2004)
4 Mbits
/
s
250
5,000,000
10 Mbits
/
s
100
2,000,000
16 Mbits
/
s
62
1,250,000
100 Mbits
/
s
19
200,000
1 Gbits
/
s
4
20,000
2 Gbits
/
s
3
10,000
10 Gbits
/
s
2
2,000
2
.
The sequence of events to determine the best received BPDU (which is the best path to the root).
Lowest root bridge ID determines the root bridge
.
Lowest cost to the root bridge favors the upstream switch with the least cost to root
.
Lowest sender bridge ID serves as a tie breaker if multiple upstream switches have equal cost to root
.
Lowest sender port ID serves as a tie breaker if a switch has multiple (non-Ether channel) links to a single
upstream switch
.
Bridge ID
=
priority (4 bits) +
locally assigned system ID extension (12 bits) +
ID [MAC Address] 48 bits
The default bridge priority is 32768
.
Port ID = priority (4 bits) +
ID (Interface number) (12 bits)
The default port priority is 128.
2.12.4 MSTP Instance
MSTP enables the grouping and mapping of VLANs to different spanning tree instances
.
Therefore, an MST
Instance (MSTI) is a particular set of VLANs that are all using the same spanning tree. Note that MSTI is identified
by MSTI number and locally significant within MST region. Figure 2.110 illustrates the MSTP Instance webpage. In
this section, the uses can add or remove MSTP instance. The upper part of the webpage is a table of existing MSTP
instance in the managed switch
.
The users can add a new MSTP instance by choosing an Instance ID from the
dropdown list, enter the VLAN Identification number in the VID field, and set the desired priority in the Priority field
.
After filling all information, please click the
Add/Modify
button to update the MSTP instance. The procedure for
setting up an MSTP instance is as follows:
Enable MSTP protocol in Section 2.12.1
Modify spanning tree main setting as described in Section 2.12.1
Select ports that you want to enable MSTP function in Section 2.12.1
Add a Multiple Spanning Tree Instance
)
MSTI
(
in MSTP Instance webpage (this section).
o
Choose an Instance Identification
o
Add VLAN Identification numbers (VIDs) that will be member(s) of MSTP instance
.
o
Set Priority value of the switch
.
o
Click
Add/Modify
button
.
Table 2.38 summarizes the descriptions of MSTP Information.