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IP Network Interface Series 3 Voice Coder Packet Rate Information

For the IP Network Interface Series 3 card there is a coupling between the Payload Type (codec) and Payload Size (packet rate). Unlike the VDAC-ONE card, the base packet rate (sampling) of a codec is different for different codecs. This implies that a Payload Size, which is defined in multiples of the base packet rate are specific to the Payload Type. The table below shows the relationship between the Payload Type and Payload Size on an IPN-3 card. It also shows a list of all Voice Coders supported by the IPN-3 card.

Table 4-2 IP Network Interface Series 3 Voice Coder Packet Rate Information

TLV Payload Type Data Value (decimal) | RTP Payload Type | Basic Packet Rate (ms) | Default Packet Rate (sampling) (ms) | Max Packet Rate (ms)
0 | G.711 A-Law (64 Kbps) | 5 ms | 4x - 20 ms | 6x - 30 ms
1 | G.711 m-Law (64 Kbps) | 5 ms | 4x - 20 ms | 6x - 30 ms
2 | G.726 (16 Kbps) | 5 ms | 4x - 20 ms | 12x - 60 ms
3 | G.726 (24 Kbps) | 5 ms | 4x - 20 ms | 12x - 60 ms
4 | G.726 (32 Kbps) | 5 ms | 4x - 20 ms | 12x - 60 ms
5 | G.726 (40 Kbps) | 5 ms | 4x - 20 ms | 12x - 60 ms
15 | G.723.1 (5.3 Kbps) | 30 ms | 1x - 30 ms | 3x - 90 ms
16 | G.723.1 (6.3 Kbps) | 30 ms | 1x - 30 ms | 3x - 90 ms
17 | G.729 (8 Kbps) | 10 ms | 2x - 20 ms | 6x - 60 ms

Internet Protocol. Part of the TCP/IP family of protocols used to route messages and tracks the addresses of nodes.
Tag-Length-Value block. A standardized block that allows data to inserted in a standard way into API messages.
Real-Time Transport Protocol. Supports transport of real-time data like interactive voice and video over packet-switched networks.
PCM and companding standard used in Europe to compress and expand the amplitude range of a signal before and after transmission. See µ-Law.