Service Providers should implement IDP discovery, i.e., allowing subjects to choose their Identity Provider from all available/desirable ones, by integrating it within their application. See the REFEDS Discovery Guide for details on why and how. ACOnet recommends using one of these Free/Libre software projects, which can be integrated with most any software or website:
Contact ACOnet for help with integrating IDP discovery into your eduID.at Service Provider.
If all else fails you can make use of one of the central "fallback" discovery interfaces provided by ACOnet.
The SWITCHwayf software may be more familiar to subjects from ACOnet institutions since an older version had been in use at