when a switch trust for example a cos priority bits in a frame on a trunk port, what i am trying to understand is i know ithe switch will attempt to build qos label based on cos bits/ if there no 802.1 or isl header, the default cos value from the interface settings is used instead!
what if there is not default settings on the interface, no classification done on the interface level, what does the switch do?
also for layer traffic such as cdp or keepalives, since they are carried over the native vlan, they have no cos fields of their own, how does the switch treat those traffic? i read that the switch will assigns a default interface value of 1?
Thanks for your help