VOIP Bandwidth consumption naturally depends on thecodecused

VOIP Bandwidth consumption naturally depends on thecodecused.

 

The bandwidth consumed by VoIP generally depends on the Speech Encoding used.
When calculating bandwidth, one can't assume that every channel is used all the time. normal conversation between des a lot of silence, which often means no packets are sent at all. so even if one voice call sets up two 64 kbit RTP streams over UDP over IP over Ethernet (which adds overhead), the full bandwidth is not used at all times.

 

When calculating bandwidth, it cannot be assumed that every channel is in use. the normal call process includes a series of mute operations, which means that packets are not always transmitted. therefore, a voice call creates two 64 kbit RTP streams (total overhead) that pass through UDP, IP, and Ethernet. All the bandwidth is used at the end.
A codec that sends a 64kb stream results in a much larger IP network stream. the main cause of the extra bandwidth usage is IP and UDP headers. voIP sends small packets and so, usually times, the headers are actually much larger than the data part of the packet.

 

The voice encoding for a 64 kB stream is mostly the result of an IP network stream. the extra bandwidth is mainly used to increase the IP address or UDP header. voIP only transmits a small number of packets. In many cases, the packet header is much larger than the packet data.
Codec BR Neb
G.711 64 Kbps 87.2 kbps
G.729 8 kbps 31.2 kbps
G.723.1 6.4 kbps 21.9 kbps
G.723.1 5.3 kbps 20.8 kbps
G.726 32 Kbps 55.2 kbps
G.726 24 kbps 47.2 kbps
G.728 16 kbps 31.5 kbps
Ilbc 15 kbps 27.7 kbps
BR = Bit Rate
Neb = nominal Ethernet bandwidth (one direction)

 

Based on my experience, 8 K g.729 is encapsulated with an IP address to reach 32 K. To prevent blocking, some users use the ip sec device to make the voice into a VPN. In this way, g.729 is encapsulated with an IP address, in addition, the VPN will reach more than 60 K.

Note: the first three paragraphs are translated by myself, so it is not very accurate to read, and it may feel awkward. sorry. if you are interested, you can try again. for reference.