A.2.1.6 Header layout for NetworkMessages with integrity and confidentiality (signing and encryption)

UADP messages may be signed and encrypted. In this case the SecurityHeader and the Signature have to be added to the message. See clause 7.2.4.4.3 for a complete description of the security mechanisms.

This header layout is basically the same as the header layout defined in A.2.1.4 but with additional security level ‘signing and encryption’.

The NetworkMessage header layout with signing is shown in Figure A.3.

Figure A.3 – UADP NetworkMessage header layout with integrity and confidentiality

Table A.4 shows the configuration for the NetworkMessage header with signing and encryption. The table contains only the added or modified rows from Table A.1.

Table A.4 – UADP NetworkMessage header layout with integrity and confidentiality
Name Type Restrictions
ExtendedFlags1ByteBit 4: SecurityHeader enabled = 1
SecurityHeader

SecurityFlags

Byte

Bit 0: NetworkMessage Signed enabled = 1

Bit 1: NetworkMessage Encryption enabled = 1

Bit 2: SecurityFooter enabled = 0

Bit 3: Force key reset enabled = 0

Bit range 4-7: Reserved

SecurityTokenId

IntegerIdThe ID of the security token that identifies the security key in a SecurityGroup.

NonceLength

Byte8

MessageNonce

Byte[8]A number used exactly once for a given security key.