Which of the following QoS packet types should have the highest priority?

A.
streaming video

B.
interactive video

C.
voice

D.
transactional data

E.
network control

Explanation:
Network control packets should have the highest priority when configuring Quality of Service (QoS) for a
network. QoS is a feature that provides strict priority service to traffic to ensure reliable delivery of the packets.
You can configure QoS so that specific classes of traffic are given higher priority than other types of traffic. For
example, in networks that utilize voice and video, you can configure the traffic so that the voice and video traffic
are given higher priority than data traffic. Providing a higher priority to voice traffic is recommended because
voice traffic is more negatively affected by delay and jitter than most transactional data traffic. However, in order
to support the network infrastructure, network control traffic should be granted a higher priority than other types
of traffic, including voice, video, and data traffic.
The Institute of Electrical and Electronics Engineers (IEEE) 802.1D standard, which incorporates components
of IEEE 802.1p, defines seven traffic types and provides recommendations on the priority values that should be
assigned to those traffic types. These traffic types are shown in the following table, with the highest-priority
packets listed first:

Cisco: LAN QoS