2.3 Unified Communications
2.3.1 Understand communication types, their purposes and functions
VoIP (Voice over Internet Protocol)
VoIP is a communication technology that allows voice calls to be made over
IP networks such as the internet. Its purpose is to convert voice signals
into digital data packets, enabling cost‑effective voice communication
across local and wide area networks.
SIP (Session Initiation Protocol)
SIP is a signalling protocol used to establish, manage, and terminate
real‑time communication sessions such as voice and video calls.
It controls call setup and teardown rather than carrying the voice data itself.
2.3.2 Understand the relationship between VoIP and SIP
Relationship Between VoIP and SIP
VoIP provides the mechanism for transmitting voice data across networks,
while SIP is used to initiate, control, and end VoIP calls.
Together, they enable real‑time voice communication over IP networks.
2.3.3 Know definitions of network metrics
Speed
Speed refers to how fast data is transmitted across a network.
It is typically measured in megabits per second (Mbps) or gigabits per second (Gbps).
Bandwidth
Bandwidth is the maximum amount of data that can be transmitted over a network
in a given period. Higher bandwidth allows more simultaneous data transfers.
Latency
Latency is the time delay between sending data and receiving it.
High latency can cause noticeable delays in voice and video communications.
Jitter
Jitter refers to variations in packet arrival times.
Inconsistent packet delivery can result in distorted or unclear audio.
Packet Loss
Packet loss occurs when data packets fail to reach their destination.
This can cause gaps in audio, dropped calls, or poor call quality.
2.3.4 Understand relationships between network metrics and user experience
Impact on User Experience
Network metrics directly affect user experience during communication.
Low bandwidth, high latency, jitter, or packet loss can result in poor
audio quality, delays, and dropped calls, reducing communication effectiveness.
2.3.5 Know and understand the purpose of codecs
Compressing Data
Codecs compress data to reduce file size and bandwidth usage.
This allows audio and video to be transmitted efficiently over networks.
Uncompressing Data
Codecs also uncompress data at the receiving end so that audio or video
can be played back in a usable format without noticeable quality loss.
2.3.6 Know different types of codecs, their purpose and algorithms
MPEG‑4
MPEG‑4 is a codec used primarily for video compression.
It can use both lossy and lossless algorithms, balancing quality
and file size depending on usage requirements.
MP3
MP3 is an audio codec that uses lossy compression.
It removes audio data that is unlikely to be noticed by human hearing,
significantly reducing file size.
FLAC
FLAC is a lossless audio codec that compresses data without removing
any original information. It is used where audio fidelity is important.