Exam 350-401 topic 1 question 869 discussion

If your phone supports CAC (this is the case with a 7925), before any call (as you punch the numbers and press the green button), the phone is going to send to the AP and Add Traffic Tream (ADDTS) request. The request contains a Traffic Classification (TCLAS) field, that basically says that this is voice 2 ways. It also contains a field called traffic specification (TSPEC) that provides all the details you need for the call: average size of packets, volume of traffic on the way up (per second), on the way down, minimum data rate needed, etc. This is what allows the AP to determine if this call can be adminteed

QoS negotiation process: 1. Traffic Classification (TCLAS) 2. Traffic Specification (TSPEC) 3. Call Admission Control (CAC)

D is correct

Right answer D. Call Admission Control (CAC) is a mechanism used in networking to manage the allocation of network resources, particularly bandwidth, to ensure that quality of service (QoS) requirements are met for real-time applications such as voice and video.