This document studies the security architecture, i.e. the security features and the security mechanisms for inter-access mobility between 3GPP access system and non-3GPP access systems. For the general architecture for inter-access mobility cf. TR 23.882]. This report is meant to provide more detail on the security aspects of inter-access mobility. The scope should be extended to the mobility between two non-3GPP access systems, which interwork with 3GPP core entities. An example would be the mobility between two WLAN access systems providing 3GPP IP access. Disclaimer: This TR reflects the discussions held in 3GPP SA3 while 3GPP SA3 was working towards TS 33.402. This TR may therefore be useful to better understand the basis on which decisions in TS 33.402 were taken, and which alternatives were under discussion. However, none of the text in this TR shall be quoted as reflecting 3GPP's position in any way. Rather, 3GPP's position on security for non-3GPP access to EPS is reflected in the normative text in TS 33.402. Information in the TR may be inaccurate and outdated. One example of outdated text can be found in clause 4.1 and clause 4.2 on alternatives for authentication protocols. The choices of authentication protocols finally made by 3GPP can be found in TS 33.401 and TS 33.402 respectively.

The following documents contain provisions which, through reference in this text, constitute provisions of the present document.

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