Table 25: Stp Path Costs - WAGO 852-1305 Manual

WAGO-ETHERNET-Zubehör 852
852-1305 8/4-Port 100BASE-T/1000BASE-SX/LX

Table 25: STP Path Costs

Transmission Speed
4 Mbps
10 Mbps
16 Mbps
100 Mbps
1 Gbps
10 Gbps
• Each "Bridge" communicates with the "Root Bridge" via the "Root Port".
The "Root Port" is the port on the switch with the lowest path costs to the
"Root Bridge" (the "Root Path Cost"). If there is no "Root Port", then the
switch becomes the "Root Bridge" for the "Spanning Tree" network
• A "Designated Bridge" is selected for each LAN segment. This bridge has
the lowest cost to the "Root Bridge" among the bridges connected to the
LAN.
Forward Time (Forward Delay)
The "Forward Time" is the maximum time (in seconds) that the switch wats
before it changes states. This delay is required because every switch must first
receive information on topology changes before it forwards frames. In addition,
each port needs time to receive information on conflicts that would make it return
to the blocking state. Otherwise, temporary data loops might result. The valid
range is 4 to 30 seconds.
Max Age
The "Max Age" is the maximum time (in seconds) that the switch can wait
without receiving a BPDU ("Bridge Protocol Data Unit", configuration message)
before attempting to reconfigure. All switch ports (except for "Designated Ports")
receive BPDUs at regular intervals. Each port that ages out STP information
(from the last BPDU) becomes the "Designated Port" for the attached LAN. If it
is a "Root Port", a new "Root Port" is selected from among the switch ports
attached to the network.
Hello Time
The "Hello Time" is the time interval in seconds between configuration messages
(BDPU "Bridge Protocol Data Unit") sent from the root switch.
Manual
1.1.0
Recommended Value Recommended Range Permissible Range
250
100
62
19
4
2
Enhanced Features
100 ... 1000
50 ... 600
40 ... 400
10 ... 60
3 ... 10
1 ... 5
91
1 ... 65535
1 ... 65535
1 ... 65535
1 ... 65535
1 ... 65535
1 ... 65535