Bit Position,Name,Description,Reference
0,Reserved,,[RFC8613]
1,Reserved,,[RFC8613]
2,Group Flag,"For using a Group OSCORE Security Context, set to 1 if the
        message is protected with the group mode",[draft-ietf-core-oscore-groupcomm-14]
3,Kid Context Flag,Set to 1 if kid context is present in the compressed COSE object,[RFC8613]
4,Kid Flag,Set to 1 if kid is present in the compressed COSE object,[RFC8613]
5-7,Partial IV Length,Encodes the Partial IV length; can have value 0 to 5,[RFC8613]
8,Extension-2 Flag,"Set to 1 if the OSCORE Option specifies a third byte, which includes the flag bits 16-23",[draft-ietf-core-oscore-key-update-03]
9-14,Unassigned,,
15,Nonce Flag,Set to 1 if nonce is present in the compressed COSE object,[draft-ietf-core-oscore-key-update-03]
16,Extension-3 Flag,"Set to 1 if the OSCORE Option specifies a fourth byte, which includes the flag bits 24-31",[draft-ietf-core-oscore-key-update-03]
17-23,Unassigned,,
24,Extension-4 Flag,"Set to 1 if the OSCORE Option specifies a fifth byte, which includes the flag bits 32-39",[draft-ietf-core-oscore-key-update-03]
25-31,Unassigned,,
32,Extension-5 Flag,"Set to 1 if the OSCORE Option specifies a sixth byte, which includes the flag bits 40-47",[draft-ietf-core-oscore-key-update-03]
33-39,Unassigned,,
40,Extension-6 Flag,"Set to 1 if the OSCORE Option specifies a seventh byte, which includes the flag bits 48-55",[draft-ietf-core-oscore-key-update-03]
41-47,Unassigned,,
48,Extension-7 Flag,"Set to 1 if the OSCORE Option specifies a eighth byte, which includes the flag bits 56-63",[draft-ietf-core-oscore-key-update-03]
49-63,Unassigned,,