You have been tasked with setting a trust boundary on the Company network. What is the
basic function of this trust boundary?

A.
Trust boundaries are points in the network where Layer 2 CoS markings are
converted to Layer 3 DSCP or IP precedence markings.

B.
Trust boundaries are a point in the network where QoS functionality begins and ends.

C.
Trust boundaries determine whether certain types of traffic can pass.

D.
Trust boundaries are a point in the network where decisions about CoS markings on
incoming packets are made.

E.
None of the other alternatives apply

Explanation:
The perimeter formed by switches that do not trust incoming QoS is called the trust
boundary. Usually, the trust boundary exists at the farthest reaches of the enterprise network
(access-layer switches and WAN or ISP demarcation points). When the trust boundary has
been identified and the switches there are configured with untrusted ports, everything else
inside the perimeter can be configured to blindly trust incoming QoS values since the
COS/QOS markings are then under the control of the network administrator, and not the end
user.