Business Phone Systems VoIP Fundamentals 3

Question 1

What is QoS in the context of VoIP networks?

Accepted Answer

Quality of Service — prioritizing voice traffic over other data

Answer

QoS (Quality of Service) prioritizes VoIP packets on the network to ensure low latency and minimal packet loss.

Question 2

What is the MOS (Mean Opinion Score) scale used for?

Accepted Answer

Rating perceived voice call quality from 1 to 5

Answer

MOS rates perceived audio quality on a scale of 1 (bad) to 5 (excellent), with 4+ considered toll quality.

Question 3

Which DSCP value is recommended for marking VoIP media traffic to ensure QoS?

Accepted Answer

EF (Expedited Forwarding, DSCP 46)

Answer

EF (Expedited Forwarding) with DSCP value 46 is the standard marking for real-time voice media to receive highest priority.

Question 4

What is a softphone?

Accepted Answer

A software application that enables VoIP calls from a computer or mobile device

Answer

A softphone is a software program installed on a computer or smartphone that provides full phone functionality over VoIP.

Question 5

What is the purpose of a STUN server in VoIP?

Accepted Answer

Helps VoIP devices discover their public IP address and NAT type

Answer

A STUN server allows VoIP clients behind NAT to discover their public IP address and port for direct media communication.

Business Phone Systems Practice Test