ECS4100 Series Web Management Guide-R07

Table Of Contents
Chapter 7
| Spanning Tree Algorithm
Configuring Global Settings for STA
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Figure 120: Configuring Port Loopback Detection
Configuring Global Settings for STA
Use the Spanning Tree > STA (Configure Global - Configure) page to configure
global settings for the spanning tree that apply to the entire switch.
Command Usage
Spanning Tree Protocol
5
This option uses RSTP set to STP forced compatibility mode. It uses RSTP for the
internal state machine, but sends only 802.1D BPDUs. This creates one
spanning tree instance for the entire network. If multiple VLANs are
implemented on a network, the path between specific VLAN members may be
inadvertently disabled to prevent network loops, thus isolating group
members. When operating multiple VLANs, we recommend selecting the MSTP
option.
Rapid Spanning Tree Protocol
5
RSTP supports connections to either STP or RSTP nodes by monitoring the
incoming protocol messages and dynamically adjusting the type of protocol
messages the RSTP node transmits, as described below:
STP Mode – If the switch receives an 802.1D BPDU (i.e., STP BPDU) after a
ports migration delay timer expires, the switch assumes it is connected to
an 802.1D bridge and starts using only 802.1D BPDUs.
5. STP and RSTP BPDUs are transmitted as untagged frames, and will cross any VLAN
boundaries.