[Standards] guest access
mwild1 at gmail.com
Fri Jun 26 11:26:54 UTC 2015
On 26 June 2015 at 00:51, Peter Saint-Andre - &yet <peter at andyet.net> wrote:
> Lance Stout and I had a conversation the other day about what we call "guest
> access" to an XMPP application. As example, consider a chat service (text,
> video, what have you) that has registered users and the ability for
> registered users to invite ad-hoc users to a session or meeting. This kind
> of functionality is quite common with applications like video conferencing
> (Talky, Jitsi Meet, WebEx, etc.).
> If this kind of application is based on XMPP, the invited user needs to gain
> access to the network (i.e., authenticate somehow) in order to join the
> conference. However, for security and scaling reasons it makes sense to have
> these ad-hoc users authenticate at a different place than the registered
> users. (Often, but not always, the ad-hoc users might "authenticate" using
> the SASL ANONYMOUS mechanism, but other methods are possible such as token
> Thus we need a way for a client to discover where it can authenticate as an
> ad-hoc or guest user. We don't want to use a DNS SRV Service name of
> "xmpp-client" because that will point clients to the service endpoint for
> registered users. What we came up with was to use a new DNS SRV Service name
> of "xmpp-guest", which would point to the service endpoint for guest access.
> Has anyone else deployed this kind of pattern? If so, how did you solve the
> problem of service endpoint discovery? Would you find it helpful to have a
> DNS SRV Service name for this kind of access?
Would a TXT record not be more appropriate? Containing the XMPP host
of a suitable place to authenticate anonymously? A SRV will tell you
where to connect to, but not which XMPP host to use. TXT gives you
both (because you can proceed with the usual SRV lookups for the guest
host, once you know it).
If you're using the same XMPP host for non-guest and guest, I don't
see the need for an extra DNS record. I don't see a use-case for for
non-guest and guest on the same XMPP host but different network hosts
(just use clustering(TM)).
Finally, if we were to use TXT, then maybe this is a candidate for
inclusion in XEP-0156?
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