[asterisk-dev] Challenging a sendonly INVITE

[Johansson Olle E]

28 jan 2008 kl. 14.03 skrev SCG2:

> Hi,
>
> Is there any circumstance at all where it makes sense to challenge  
> an INVITE which is putting a call on hold?
>
> I can find nothing in 3264 that suggests it, but wondered if:
>
> Phone A -> Phone B (in doing so phone A may have been authenticated)
> Phone B later goes to put phone A on hold
>
> The only authentication Phone B has had prior to this interaction is  
> the implicit REGISTER challenge response that may have been several  
> minutes ago.
>
> Is that good enough?
>
I would say that it's up to the implementation when to challenge. You  
can make an assumption here that
phone B is within a current dialog. B could have authenticated A on  
the first INVITE. Or a proxy between
A and B could have.

A has the right to authenticate B on the re-invite if it wants to,  
since the music on hold music is licensed
from ABBA and only authenticated users are allowed to put anyone on  
hold and listen in... :-)

Normally you separate re-invites from initial invites and say that  
since B knows the tags, the caller ID
and is involved in the call, we'll accept the invite without  
authentication.

/O