What is one of the reasons that custom QoS ACLs are recommended over automatic QoS when
configuring ports on a Catalyst 6500 for use with IP phones?
A.
79xx IP phones do not automatically mark voice packets with non-zero DSCP values.
B.
79xx IP phones do not mark protocol packets such as DHCP, DNS, or TFTP with non-zero DSCP values.
C.
79xx IP phones do not mark voice packets with optimal DSCP values.
D.
79xx IP phones use a custom protocol to communicate CDP information to the switch.
the correct answer should be:
Answers: C
79xx IP phones do not mark voice packets with optimal DSCP values.