Can you please help me clear this up.
I am confused about DSCP trust boundaries. I understand that COS is Layer 2 and it is stripped off at the router.
But what about DSCP? The IP portion of the packet is not stripped so why whould there be a need to trust DSCP?
Is the DSCP cleared at the switch if DSCP is not trusted? i.e. a phone marks a packet with EF. What happens to that marking with a) mls qos trust dscp and b) not trusted.
Thanks for your help,