Date: 7th December 2017 / Version: 1.1 / Status: Experimental

This document specifies a mechanism for STANAG 5066 implementations to specify which STANAG 5066 Extensions (S5066-EP series) they support. This enables capability information to be shared, which will improve interoperability and backwards compatibility.

This document is part of the STANAG 5066 Extension Protocol (S5066-EP) series. The complete set of documents in the series are:

  1. STANAG 5066 Extension Protocol Index (S5066-EP1)
  2. STANAG 5066 Padding DPDU (S5066-EP2)
  3. Pipelining the CAS 1 Linking Protocol (S5066-EP3)
  4. Data Rate Selection in STANAG 5066 for Autobaud Waveforms (S5066-EP4)
  5. STANAG 5066 Large Windows Support (S5066-EP5)
  6. Slotted Option for STANAG 5066 Annex K (S5066-EP6)
  7. Advertising Extended Capabilities (S5066-EP7)
  8. Block Based EOTs (S5066-EP8)
  9. Compact Acknowledgement (S5066-EP9)
  10. Extension DPDU (S5066-EP10)
  11. Variable C_PDU Segment Size (S5066-EP11)
Creative Commons License

1. Model of Use

This specification defines an EOW format that can be used by a STANAG 5066 implementation to communicate its capabilities to its peers. It is transferred in a DPDU as a standard EOW. An implementation supporting this specification shall from time to time send it to each peer. An implementation supporting this specification shall record capability information of peers and shall update this information if a subsequent extended capability EOW is received.

If this information shows that a peer does not support a capability this capability shall not be used. If this information shows that a peer does support a capability this capability may be used.

2. Extended Capabilities EOW Specification

The Extended Capabilities EOW is specified below. This uses EOW Type 15. This is specified with least significant bit first.

Bit Field Number of Bits Comment
S5066-EP2 1 Set to 1 if S5066-EP2 (Padding DPDU) is supported
S5066-EP3 1 Set to 1 if S5066-EP3 (Pipelining CAS 1) is supported
S5066-EP4 1 Set to 1 if S5066-EP4 (Data Rate Selection) is supported
S5066-EP5 1 Set to 1 if S5066-EP5 (Large Window Support) is supported
S5066-EP6 1 Set to 1 if S5066-EP6 (Annex K slotted option) is supported
S5066-EP8 1 Set to 1 if S5066-EP8 (Block based EOT) is supported
S5066-EP9 1 Set to 1 if S5066-EP9 (Compact Acknowledgement) is supported
S5066-EP11 1 Set to 1 if S5066-EP11 (Variable C_PDU Segment Size) is supported

3. Backwards Compatibility

This specification uses a spare EOW type, which will be ignored by implementations that do not support this specification. It enables implementations that do use this specification to determine peer capability which will enable safe use of STANAG 5066 extensions.