Now, after discussing different protocols,
standards, and codecs, let's discuss the components of any VoIP call.
Each call has two components.
First is signaling, which is the process of establishing,
modifying, and terminating a VoIP call.
Call signaling is typically handled by a signaling protocol such as SIP or H323.
Once the call signaling is completed,
audio and video dataflow between two or more parties starts.
This is called media flow, which is a second component of any call.
It is typically handled by a transport protocol,
such as Real‑time Protocol, RTP.
More than just basic end‑two‑end audio calls,
today, VoIP systems are feature rich.
We need media servers to provide additional features and functionality,
such as voicemail, conference calling, call recording.
They can be hardware or software‑based,
and they typically use protocols such as SIP and RTP
to communicate with other devices.
Okay, great.
We know different VoIP protocols, codecs, and how they set up a call.
Now let's discuss what is QoS.
QoS refers to the quality of service by the underlying communication network.
QoS is measured in terms of factors such as delay, jitter, and packet loss.
We discussed delay, jitter, and packet loss in the previous module as well.
For example, a user makes a VoIP call using SIP‑based phone system.
The QoS of the call is determined by the delay,
jitter,
and packet loss experienced by the user's voice data
as it travels over the network.
VoIP is sensitive to change in network conditions,
as even a small amount of delay, jitter,
or packet loss can negatively impact the quality of the call.
Good QoS is, therefore, crucial for providing a satisfactory VoIP experience.
As for the poor QoS during a VoIP call,
resulting in choppy audio and difficulty in understanding the other party.
This can be frustrating for both parties and merely to a poor user experience.
There are a number of ways to improve QoS for VoIP,
including prioritizing VoIP traffic over other types of
traffic can help reduce delays and jitters.
Marking VoIP packets with a QoS tag can help ensure that they are treated
with an appropriate level of priority by network devices.
Additionally,
managing bandwidth usage ensures that sufficient
bandwidth is always available for VoIP calls.
For example, a user experiences poor call quality during a web call.
The administrator of the VoIP system implements QoS marking and bandwidth
management measures in the network to improve call quality.
As a result,
you may find that the user experience now improved audio quality and a better overall VoIP experience.