1.2.3 Bandwidth Requirements
Router Requirements
•Port Forwarding:
It may be necessary to set the NAT router so that it forwards the incoming packets to the IP address of the
–the PBX uses a STUN server;
–a
–incoming packets are routed to a SIP Client port or NAT Voice (RTP) UDP port indicated in the [IP Packets to
•
When a
recommended to disable this feature.
*1 | When NAT is enabled, the router translates the IP address stored in the IP header and the port number stored in the UDP header. |
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| When |
1.2.3 Bandwidth Requirements
When using the
Note that the amount in the table is only a guide. Subscribe to a network that has enough bandwidth. If the amount of bandwidth required for VoIP communications is larger than what the network can accommodate, speech quality will be compromised.
Required Bandwidth for Each Channel
The required bandwidth depends on what combination of CODECs and packet sending interval is used. Keep in mind the following points about the type of CODEC and packet sending interval, in terms of the speech quality:
•The speech quality of the CODECs varies as follows: G.711 (High), G.729 (Low)
•The shorter the packet sending interval, the higher the speech quality.
•The higher the speech quality the
CODEC |
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| Packet Sending Interval |
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10 ms |
| 20 ms |
| 30 ms |
| 40 ms |
| 50 ms |
| 60 ms | |||
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G.711 | 110.4 kbps |
| 87.2 kbps |
| 79.5 kbps |
| 75.6 kbps |
| 73.3 kbps |
| 71.7 kbps | ||
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G.729 | 54.4 kbps |
| 31.2 kbps |
| 23.5 kbps |
| 19.6 kbps |
| 17.3 kbps |
| 15.7 kbps | ||
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8
Programming Manual for Virtual SIP Trunk Card