(11) "Hash Message Authentication Code
" from http://en.wikipedia.org/wiki/HMAC.
* M-ACTripleDES (Message Authentication Code
The sender breaks the confidential digital message into packets and tags each packet with a short string of digits known as a message authentication code
. The message packets can then be intermingled with fake packets bearing bogus authentication codes to create a plausible missive.
The first phase of a Federal Reserve effort to test emerging commercial message authentication code
products that meet national standards has just been completed.
Multisignature and Aggregate Message Authentication Code
. In 1983, the multisignature scheme was firstly proposed by Itakura and Nakamura , in which a lot of signers can cooperate to sign the same message and any verifier can verify the validity of the multisignature.
A common approach to doing this involves generating a tag (commonly called a Message Authentication Code
, or MAC) that depends, in a complex way, on all the bits in the message body.
(iv) a pair of message authentication code
(MAC) generation/verification algorithms (Mac, Ver), where Ver outputs a bit, with 1 meaning accept and 0 meaning reject.
AP-2: sensor [S.sub.n] generates [M.sub.2] = <[B.sub.k], [AID.sub.k], Tu, Ts, [S.sub.n]> and sends message <[M.sub.2], Q> to GW node; here [MATHEMATICAL EXPRESSION NOT REPRODUCIBLE IN ASCII] is a message authentication code
After that, these parameters are indirectly transformed secretly into the message authentication code
(MAC) during an update session.
A similar application is to embed information for authentication of the contents, such as message authentication code
and digital signature, so that tampering against digital contents can be detected afterwards.
To evaluate security techniques, Soderlund  studied the impact of adding a message authentication code
on the lifetime of the WSN based on different symmetric and asymmetric approaches.
In view of resource constrained devices used in most M2M applications, it uses the lightweight symmetric key based aggregate Message Authentication Code
(MAC) approach with integrity verification of authentication messages at each level of the hierarchy.