Allied Telesis AT-S63 - Manual (Page 615)

AT-S63 Management Software Menus Interface User’s Guide
Section V: VLANs 615
Note
When the uplink port receives a packet with a destination MAC
address that is not in the MAC address table, the port broadcasts the
packet to all switch ports. This can result in ports receiving packets
that are not intended for them.
Also note that a switch operating in this mode can be remotely
managed through any port on the switch, not just the uplink port.