Section: 6.4.4.1 NAS input parameters to confidentiality algorithm
Content: The input parameters for the NAS 128-bit ciphering algorithms shall be the same as the ones used for NAS integrity protection as described in clause 6.4.3, with the exception that a different key, KNASenc, is used as KEY, and there is an additional input parameter, namely the length of the key stream to be generated by the encryption algorithms. The use and mode of operation of the 128-bit ciphering algorithms are specified in Annex D. NOTE: In the context of the present subclause 6.4.4, a message is considered ciphered also when the NULL encryption algorithm NEA0 is applied.