Open Source IMS Client

For VoWiFi, we need an IPsec implementation that has been extended with the requirements for the 3GPP SWu interface, specifically

• the EAP-AKA mechanism for UMTS-AKA based authentication
• some external interface to access a USIM for authentication

We've been evaluating two different paths here:

• https://github.com/fasferraz/SWu-IKEv2 - rather hackish python codebase, laforge had difficulties getting it to work with at least two IMS operators
• a slightly modified version of strongswan. domi has been doing some development about this. laforge had more success with this, at least to establish the SWu tunnel successfully once - it then failed in subsequent operations.