STANAG 5066 has been updated to Edition 4. This page provides easy access to the ratification document as well as all previous draft versions, to facilitate review and comment. This page also lists annexes which have been removed from Edition 4, with a short rationale for the removal. The latest version of each annex and the main body are also provided as separate documents. Each annex and the main body have an independent version number and date. Each Annex has a section noting changes from Edition 3.


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STANAG 5066 Ed4 Ratification

STANAG 5066 Ed4 has now reached Ratification stage, meaning that it is now technically complete. Ed4 is now being voted on by NATO nations to become a full (promulgated) standard. You can read the full Ed4 Ratification document here.

STANAG 5066 Ed4 Draft Versions

Although STANAG 5066 Ed4 has now been ratified, the previous draft versions are listed below and will be kept publicly available for prosperity.

Draft Version 1.0 (April 20th 2020) of STANAG 5066 Edition 4 is here.

Draft Version 1.2 (January 14th 2021) of STANAG 5066 Edition 4 is here.

Draft Version 1.4 (March 25th 2021) of STANAG 5066 Edition 4 is here.

Draft Version 1.5 (April 6th 2021) of STANAG 5066 Edition 4 is here.

Draft Version 1.6 (August 27th 2021) of STANAG 5066 Edition 4 is here.

Separate main body and annexes are listed in the table below, with technical content identical to Ed. As testing is carried out, the annexes are updated and listed as Errata documents in a secondary table below.

Main Body

Annex A: Subnetwork Interface Sublayer

Annex B: Channel Access Sublayer. An Errata document for this Annex is available below.

Annex C: Data Transfer Sublayer. An Errata document for this Annex is available below.

Annex D: Interface between Data Transfer Sublayer and Communications Equipment.

Annex E: HF Modem Remote Control Interface. Recommended to remove.  This serial control interface has not proved useful.  Any interface would need updating for new waveforms, bandwidths, modern modem control and ALE.    There does not appear to be industry desire to work on this. Modern modem interfaces are complex and vary between vendors.

Annex F: SAP Assignment

Annex G: Use of Waveforms at Data Rates Above 2400 bps.  Recommended to remove. This is covered in updated Annex C, and there is no need for a separate annex.

Annex H: Implementation Guide and Notes.  Recommended to remove. Much of this is obsolete and coverage is selective and eccentric. Some aspects are out of data. The annex feels old and incomplete. Leaving the annex “as is” seems highly undesirable. The benefits of updating this annex seem unclear, and it would be a lot of effort.  Some key points are included in other annex updates.

Annex I: Messages and Procedures for Frequency Change.   Recommended to remove.  This is a fragile and inefficient procedure.  Frequency selection in modern systems is handled by ALE and this annex is obsolete.

Annex J: General Requirements for Enhanced Media-Access-Control (MAC) Capabilities in Multi-Node STANAG 5066 Networks.

Annex K - High-Frequency Carrier-Sense Multiple-Access Protocol. An Errata document for this Annex is available below.

Annex L - High-Frequency Wireless-Token-Ring-Protocol (WTRP) Requirement

Annex M: Adaptive Time-Division Multiple-Access (ATDMA) Protocols using STANAG 5066 DTS Layer Messaging (this annex is currently empty, with the title as a placeholder).  No changes needed.

Annex N: Guidance on Address Management in STANAG 5066 Networks.

Annex O: HF Operator Chat

Annex P: ACP 127 & Character-Oriented Serial Stream

Annex Q: ACP 142

Annex R: Routing Sublayer

Annex S: SIS Access Protocol. An Errata document for this Annex is available below.

Annex T: STANAG 5066 TRANSEC Crypto Sublayer using AES and other Protocols

Annex U: IP Client

Annex V: Compressed File Transfer Protocol

Since the ratification version was distributed, a number of errors have been identified. Corrections for these are included in the Errata documents below. It is anticipated that these Errata versions will be included in the final promulgated version of Ed4.

Clean Version Change-barred relative to ratification version

Annex B Errata

Annex B Errata with changes

Annex C Errata

Annex C Errata with changes

Annex K Errata

Annex K Errata with changes

Annex S Errata

Annex S Errata with changes