The mailing list for users of the eduroam Configuration Assistant Tool (CAT)

[Zenon Mousmoulas <zmousm AT noc.grnet.gr>]

On 2015-11-06 09:58, Stefan Winter wrote:
> [...]
> > Let decide each NREN whether they want to set up an own CAT or
> > not. What is the problem to have separated CAT instances?
>
> In an offline discussion, I gave a very detailed explanation of the
> *technical* problem we are starting to encounter just now - precisely
> because CAT continues to evolve.
>
> We now support Android; and the de-facto standard distribution for
> Android apps is the Google Play Store. We can only upload a binary
> version of our app which needs to be pre-set to contact the IdP
> discovery API.
>
> Making the API server to contact configurable defeats the purpose of 
> the
> app; it is supposed to make eduroam easier to configure by not 
> requiring
> to enter configuration details - and an API endpoint configuration is
> exactly one of the obscure technical things we do not want users to 
> ever
> see.
>
> As a consequence, right now the IdP discovery feature in the Android
> works for everyone on the planet except users in Germany because the 
> API
> endpoint is different and "our" instance knows nothing about Germany.
>
> That is one of those situations where multiple instances of the CAT
> service *do* present harm/inconvenience/annoyance to end users.
>
> I don't know if we are able to kit this problem. It would either 
> require
> significant amounts of coding (an API "proxy" which knows how which "n"
> CAT servers to query, and merge the results from those servers, and 
> send
> the merged results onwards to the app; please contribute code if you
> find that a desirable option), or be otherwise unpleasant - it is e.g.
> possible to tell the Play Store to exclude an app from specific 
> national
> markets.

Mobile (helper) applications, such as eduroam CAT for Android, surely 
need to point to a default CAT instance and that should definitely be 
cat.eduroam.org. Merging results from various instances does not seem 
realistic. I imagine however that it would not be too hard to have an 
opt-in registry of CAT instances. The app could then query this registry 
for available API endpoints or allow user input in an "advanced 
preferences" UI that would allow changing the active CAT instance. Would 
that work?

Cheers,
Z.