Allied Telesis AT-S63 - Manual (Page 245)

AT-S63 Management Software Features Guide
Section V: Spanning Tree Protocols 245
Mixed STP and RSTP Networks
RSTP IEEE 802.1w is fully compliant with STP IEEE 802.1d. Your network
can consist of bridges running both protocols. STP and RSTP in the same
network can operate together to create a single spanning tree domain.
If you decide to activate spanning tree on the switch, there is no reason
not to activate RSTP on the AT-9400 Switch even when all other switches
are running STP. The switch can combine its RSTP with the STP of the
other switches. The switch monitors the traffic on each port for BPDU
packets. Ports that receive RSTP BPDU packets operates in RSTP mode
while ports receiving STP BPDU packets operate in STP mode.