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Whitepapers HF Radio

Extension DPDU (S5066-EP10)

This document provides a framework for specifying future DPDU’s. This document is part of the STANAG 5066 Extension Protocol (S5066-EP) series. The complete set of documents in the series is available here.

1. Motivation

STANAG 5066 left six spare DPDU type values for future protocol extension. Four of these have been used by S5066-EP5 and a fifth by S5066-EP2. This specification uses the last spare value to define an extension mechanism so that further DPDUs may be added in future extension specifications

2. Extension DPDU

MSB
1		 6 5 4 3 2 1 LSB
0
0 DPDU Type = 13 EOW Type
1 EOW
2 EOT
3 Size of Address Field (m) Size of header (h)
3+m Source and Destination Address
4+m* MSB Extended DPDU Type LSB
Optional Header Bytes that may be specified in Extended DPDU
CRC CRC on Header
CRC
h+m Optional Bytes that may be specified in Extended DPDU

 

The Extension DPDU defines one byte, the Extended DPDU Type, which can have values from 0-255. This value may be used in future specifications, which may define additional header bytes and the format of data after the header.

3. Backwards Compatibility

This specification uses a standard encoding and is fully backwards compatible.

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