S3#8, Sophia Antipolis, 16-19 November 1999  	S3-99457

Title: 	Liaison Statement to RAN2 on ciphering complexity

To: 	TSG RAN2

Source: 	TSG SA WG3

S3 has received the LS on ciphering complexity (TSGR2#8(99)g83 = S3-99431).

S3 confirms that there is neither a security requirement to change nor to keep the mask. (From a security point of view in principle it would be better not to change the mask, provided that the plain text is exactly the same, however this is not a requirement: The cipher algorithm is designed to protect against known/chosen text attacks.)