Codec2 data can be encapsulated in raw ethernet frames. The codec settings are encoded into the type field. This allows the voice data to share a channel with other data flows such as location data or TCP/IP.
DML data packet:
| 0 - 7 | 8 - 15 | 16 - 23 | 24 - 31 | 32 - 39 | 40 - 47 | 48 - 55 | 56 - 63 | 64 - 71 | 72 - 79 | 80 - 87 | 88 - 95 | 96 - 103 | 104 - 111 | 112 - 119 | 120 - 127 | 128 - |
| 0 - 5 | 6 - 11 | 12 - 13 | 14 | 15 | 16 - | |||||||||||
| 48 bit address | 48 bit address | 16 bit type | 8 bit transmission nr. | 8 bit level | Codec2 frame size | |||||||||||
| Destination | Source |
3200 bits/s: 7300 2400 bits/s: 7301 1600 bits/s: 7302 1400 bits/s: 7303 1300 bits/s: 7304 1200 bits/s: 7305 700 bits/s: 7306 700B bits/s: 7307 |
0: infinite 1: -127dBm 255: 0dBm |
Codec2 voice frame data | ||||||||||||
|
A-Law: 7365 |
A-Law voice data | |||||||||||||||
|
Control: 7342 |
Control side channel data. E.g. varicode channel in FreeDV modes or DTMF on analog modes. | |||||||||||||||