Presence and IntComm WG

[Steve Blair <>]

I didn't reply-all on my original response.


Steve Blair wrote:

>  Ahh, I'm glad to see you are checking on what I say :-)
>
>  In my mind the issue exists regardless which institutions we
> are discussing. I can imagine a situation where multiple
> proxies are used and the address syntax between them is unclear.
> I'm just curious if I am off-base on this or if it could become
> an addressing issue.
>
>  In our case isc.upenn.edu is a phantom SRV record. It just
> happens to match the domain name in my PALs account. In reality
> this is a test name defined for the sole purpose of controling
> the inbound ring count to our SER proxy. It has nothing to do
> with PALs, our SIP.edu implementation and most likely won't
> remain.
>
> -Steve
>
> Candace Holman wrote:
>
> > Steve - it looks like UPenn has both isc.upenn.edu and upenn.edu 
> > activated as SRV records.  They point to different proxies and have 
> > the same preference.
> >
> > Candace
> >
> > At 04:15 PM 2/11/2005, Steve Blair wrote:
> >
> > > Candace:
> > >
> > >  Based on past conversations about SIP.edu I use the SRV name
> > > _sip._udp.upenn.edu. This is not the domain name in my email
> > > address (which is used by PALs) nor is it the domain name for
> > > our VoIP proxy. That is kinda why I am asking. It just seems to
> > > me that the domain names should "line up" at some point to make
> > > cross-environment SIP routing work.
> > >
> > > -Steve
> > >
> > > Candace Holman wrote:
> > >
> > > > It's the SRV record that makes the domains work.  You can have a 
> > > > SRV record without an A record.  It doesn't have to be resolvable 
> > > > as an A record.  Your SRV record is _sip._udp.isc.upenn.edu  Are 
> > > > you using something different for sip.edu?  I may be 
> > > > misunderstanding the issue, just ignore me if so.
> > > >
> > > > Candace
> > > >
> > > > At 03:51 PM 2/11/2005, Steve Blair wrote:
> > > >
> > > > >  Has anyone thought about the impact of domain names on
> > > > > SIP routing, especially inter-institution?
> > > > >
> > > > >  I noticed that eyebeam, and others, append the locally configured
> > > > > SIP domain name to an outgoing "called number". This is fine
> > > > > if that domain name is "resolvable". What happens when local
> > > > > SIP proxies, SIP.edu proxies and now the PALs proxy all
> > > > > interact?
> > > > >
> > > > >  During the test call with Candace I noticed some missed calls
> > > > > to 
> > > > >
> > > > >  and outbound calls had this same domain
> > > > > name appended. This domain name is not resolvable.
> > > > >
> > > > >  Our SIP.edu domain is trying to follow the architectural direction
> > > > > of using <userid>@<institution-name>.edu. Our VoIP proxy is
> > > > > known by yet another domain and PALs uses my email address.
> > > > >
> > > > >   I know we can use the alias command in SER to handle domain
> > > > > names as long as userids are understood. I am just curious what
> > > > > others think about this issue?
> > > > >
> > > > > -Steve