Edge Port; P2P Port; 802.1D/802.1W/802.1S Compatibility - D-Link DES-3526 - Switch - Stackable User Manual

xStack
802.1d MSTP
Discarding
Discarding
Discarding
Learning
Forwarding
RSTP is capable of a more rapid transition to a forwarding state - it no longer relies on timer configurations - RSTP compliant
bridges are sensitive to feedback from other RSTP compliant bridge links. Ports do not need to wait for 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.

Edge 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.

P2P 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.

802.1d/802.1w/802.1s Compatibility

MSTP or RSTP can interoperate with legacy equipment and is capable of automatically adjusting BPDU packets to 802.1d format
when necessary. However, any segment using 802.1d 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.
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.
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DES-3500 Series Layer 2 Stackable Fast Ethernet Managed Switch User Manual
802.1w RSTP
Discarding
Discarding
Discarding
Learning
Forwarding
Table 6- 1. Comparing Port States
802.1d STP Forwarding
Disabled No
Blocking No
Listening No
Learning No
Forwarding Yes
50
Learning
No
No
No
Yes
Yes