Spanning Tree Protocols; Stp And Rstp - ZyXEL Communications MSC1024G Series User Manual

Chapter 15 Switch Screens
Table 245 Switch Setup Isolation (continued)
LABEL
Select
Select All

15.9 Spanning Tree Protocols

The switch supports Spanning Tree Protocol (STP), Rapid Spanning Tree Protocol (RSTP)
and Multiple Spanning Tree Protocol (MSTP) as defined in the following standards.
• IEEE 802.1D Spanning Tree Protocol
• IEEE 802.1w Rapid Spanning Tree Protocol
• IEEE 802.1s Multiple Spanning Tree Protocol

15.9.1 STP and RSTP

RSTP adds rapid reconfiguration capability to STP. The switch supports RSTP and the earlier
STP. RSTP and STP detect and break network loops and provide backup links between
switches, bridges or routers. They allow a device to interact with other RSTP or STP-aware
devices in your network to ensure that only one path exists between any two stations on the
network. The switch uses RSTP by default but can still inter-operate with STP switches
(although without RSTP's benefits).
The root bridge is the base of the spanning tree; it is the bridge with the lowest identifier value
(MAC address). Path cost is the cost of transmitting a frame onto a LAN through that port. It is
assigned according to the speed of the link to which a port is attached. The slower the media,
the higher the cost - see the following tables.
Table 246 STP Path Costs
LINK
SPEED
4Mbps
10Mbps
16Mbps
100Mbps
1Gbps
10Gbps
Table 247 MSTP/RSTP Path Costs
LINK
SPEED
<= 100 Kbps 200 000 000
1 Mbps
480
DESCRIPTION
Select an entry's Select check box and click Delete to remove the entry.
Clicking Delete saves your changes to the MSC's volatile memory.
The MSC loses these changes if it is turned off or loses power, so use the Config
Save link on the navigation panel to save your changes to the non-volatile
memory when you are done configuring.
Select this check box to select all of the column's check boxes. Clear this check
box to clear all of the column's check boxes.
RECOMMENDED VALUE
250
100
62
19
4
2
RECOMMENDED VALUE
20 000 000
RECOMMENDED RANGE
100 to 1000
50 to 600
40 to 400
10 to 60
3 to 10
1 to 5
RECOMMENDED RANGE
200 000 000 to 200 000 000
2 000 000 to 200 000 000
MSC1000G/1024G/1224G Series User's Guide
ALLOWED
RANGE
1 to 65535
1 to 65535
1 to 65535
1 to 65535
1 to 65535
1 to 65535
ALLOWED
RANGE
1 to 200 000 000
1 to 200 000 000