RFC 6655, "AES-CCM Cipher Suites for Transport Layer Security (TLS)", July 2012Source of RFC: IETF - NON WORKING GROUP
Area Assignment: sec
See Also: RFC 6655w/ inline errata
Errata ID: 3761
Publication Format(s) : TEXT
Reported By: Sandeep S. Kumar
Date Reported: 2013-10-22
Verifier Name: Sean Turner
Date Verified: 2014-01-14
Section 3 says:
In DTLS, the 64-bit seq_num is the 16-bit epoch concatenated with the 48-bit seq_num.
It should say:
In DTLS, the 64-bit sequence number is the 16-bit epoch concatenated with the 48-bit sequence_number in the order they appear on the wire.
In DTLS 1.2 (RFC 6347, Sec 4.3.1.), the 48 bit sequence number is indicated as sequence_number. There is no mention of seq_num in the DTLS RFC.
The additional ordering information is used to keep it consistent with MAC computation in DTLS RFC 6347, Sec 184.108.40.206.)