DWS-3160 Series Gigabit Ethernet Unified Switch Web UI Reference Guide
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the topology to stabilize before transitioning to a forwarding state. In order to allow this rapid transition, the protocol
introduces two new variables: the edge port and the point-to-point (P2P) port.
The edge port is a configurable designation used for a port that is directly connected to a segment where a loop
cannot be created. An example would be a port connected directly to a single workstation. Ports that are
designated as edge ports transition to a forwarding state immediately without going through the listening and
learning states. An edge port loses its status if it receives a BPDU packet, immediately becoming a normal
spanning tree port.
Edge Port
A P2P port is also capable of rapid transition. P2P ports may be used to connect to other bridges. Under
RSTP/MSTP, all ports operating in full-duplex mode are considered to be P2P ports, unless manually overridden
through configuration.
P2P Port
MSTP or RSTP can interoperate with legacy equipment and is capable of automatically adjusting BPDU packets to
802.1D-1998 format when necessary. However, any segment using 802.1D-1998 STP will not benefit from the
rapid transition and rapid topology change detection of MSTP or RSTP. The protocol also provides for a variable
used for migration in the event that legacy equipment on a segment is updated to use RSTP or MSTP.
802.1D-1998/802.1D-2004/802.1Q-2005 Compatibility
The Spanning Tree Protocol (STP) operates on two levels:
1. On the switch level, the settings are globally implemented.
2. On the port level, the settings are implemented on a per-user-defined group of ports basis.
STP Bridge Global Settings
On this page the user can configure the STP bridge global parameters.
To view the following window, click
L2 Features > Spanning Tree > STP Bridge Global Settings
, as show below:
Figure 7-28 STP Bridge Global Settings window
The fields that can be configured are described below:
Parameter
Description
STP State
Use the radio button to globally enable or disable STP.
STP Version
Use the drop-down menu to choose the desired version of STP:
STP
- Select this parameter to set the Spanning Tree Protocol (STP) globally on
the switch.
RSTP
- Select this parameter to set the Rapid Spanning Tree Protocol (RSTP)
globally on the Switch.
