D-Link DES-3250TG User Manual page 37

DES-3250TG Layer 2 Fast Ethernet Switch User's Guide
Forwarding Forwarding Yes Yes
Table 5- 1. Comparing Port States
RSTP is capable of 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, all ports
operating in full-duplex mode are considered to be P2P ports,
unless manually overridden through configuration.
802.1d/802.1w Compatibility
RSTP can interoperate with legacy equipment and is capable of
automatically adjusting BPDU packets to 802.1d format when
necessary. However, any segment using 802.1 STP will not
benefit from the rapid transition and rapid topology change
detection of RSTP. The protocol also provides for a variable
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