The VOIP calculation method is as follows:
Bandwidth = packet length × number of packets per second
= packet length × (1/packaging period)
= (Ethernet header + IP header + UDP header + RTP header + payload) × Packets per second
= (112bit + 160bit + 64bit + 96bit + payload) × number of packets per second
= (112bit + 320bit + payload) × number of packets per second
= (432bit + payload) × number of packets per second
= (432bit × number of packets per second) + (payload × number of packets per second)
= (432bit × 1000 / packing cycle) + encoding rate
= (432bit/packaging period) Kbps + encoding rate
According to the above formula:
G711: 20ms package, bandwidth is ( 432/20 ) Kbps + 64Kbps = 85.6Kbps
G729: 20ms package, bandwidth is ( 432/20 ) Kbps + 8Kbps = 29.6Kbps
G723: 5.3k, 30ms packed, bandwidth is ( 432/30 ) Kbps + 5.3Kbps = 19.7Kbps
G723: 6.4k, 30ms packed, bandwidth is ( 432/30 ) Kbps + 6.4Kbps = 20.8Kbps
According to the above formula, the Ethernet header is not included:
G711: 20ms package, bandwidth is (320/20 + 64) Kbps=80 Kbps
G729: 20ms package, bandwidth is (320/20 + 8) Kbps = 24 Kbps
G723: 5.3k, 30ms packed, bandwidth is (320/30 + 5.3) Kbps = 15.97Kbps
G723: 6.4k, 30ms packed, bandwidth is (320/30 + 6.4) Kbps=17.07Kbps
If the server forwards the media, both the voice of the calling party and the called party need to pass through the server, so the bandwidth usage needs to be multiplied by 2, refer to the following table.
