CompTIA Security+ Question L-41

A router has a single Ethernet connection to a switch. In the router configuration, the Ethernet interface has three sub-interfaces, each configured with ACLs applied to them and 802.1q trunks.
Which of the following is MOST likely the reason for the sub-interfaces?

A. The network uses the subnet of 255.255.255.128.
B. The switch has several VLANs configured on it.
C. The sub-interfaces are configured for VoIP traffic.
D. The sub-interfaces each implement quality of service.

Answer: B

Explanation:
A subinterface is a division of one physical interface into multiple logical interfaces. Routers commonly employ subinterfaces for a variety of purposes, most common of these are for routing traffic between VLANs. Also, IEEE 802.1Q is the networking standard that supports virtual LANs (VLANs) on an Ethernet network.

CompTIA Security+ Question K-34

Which of the following should be performed to increase the availability of IP telephony by prioritizing traffic?

A. Subnetting
B. NAT
C. Quality of service
D. NAC

Answer: C

Explanation:
Quality of Service (QoS) facilitates the deployment of media-rich applications, such as video conferencing and Internet Protocol (IP) telephony, without adversely affecting network throughput.