thank you Jerome
these informations very helpful for me ..but i want to know is it possible to configured in siemens PSTN (ewsd or powernode )
if one of the DPC in the ‘disallow’ list try to use our switch as STP what’s the situation in his side..he can know i put him in disallow list??
and can i know this DPC trying to use our switch as STP
thank you so much