Company wants to use their existing data network for VOIP use. What three statements are
true for networks that are enabled for voice as well as data traffic? (Choose three)

A.
Redundant hardware, redundant links, UPS, and proactive network management are
data network standards that do not apply to voice networks.

B.
The increased costs of voice enabled networks are offset by increased worker
productivity.

C.
High availability networks must be created to avoid network congestion and
overcome a lack of redundancy and poor engineering.

D.
An uptime of 99.999 percent is achieved using a 4-hour service response contract for
system problems.

E.
Auxiliary VLANs provide the ability to apply QoS to voice traffic without affecting the
flow of data from the client PC.

F.
For ease of implementation, most VoIP phones use in-line power to get power
through the same cable on which data is sent.

Explanation:
When adding voice or video to an existing network, you should examine several things in
advance to provide the high level of availability users expect in their phone system:
What features are needed?— Power for IP phones, voice VLANs on the switches, network
redundancy for high availability, security for voice calls, and Quality of Service (QoS)
settings.
Electrical power for the IP phones— Use either inline power from Catalyst switch or power
patch panel. Need uninterruptible power supply (UPS) with auto-restart, monitoring, and 4-
hour response contract. May need generator backup. Maintain correct operating
temperatures.
Auxiliary (or Voice) VLANs
Cisco switches can be configured to dynamically place IP telephones into a VLAN separate
from the data VLANs. They can do this even when the phone and PC are physically
connected to the same switch port. This is called an auxiliary VLAN or a voice VLAN. Voice
VLANs allow phones to be dynamically placed in a separate IP subnet from hosts, to have
QoS (using 802.1Q/p headers) and security policies applied, and makes troubleshooting
easier.
Reference: Cisco CCNP BCMSN Quick Reference Sheets, chapter 7, page 53