[Asterisk-Dev] PROGRESS messages with Cause 17 (User Busy) - Bug # 4250

[Peter Svensson]

On Mon, 23 May 2005, Clint Guillot wrote:

> Is it a violation of Q.931 for a PROGRESS message to contain a cause 
> code 17 (User busy), AND for this to be the only indication that a call 
> has failed with a busy condition?
> Is a HANGUP message not required in this instance?

Looking at table I.2 in q.931 the normal operation is certainly for that
cause code to be received as as a DISCONNECT by the originating caller. 
5.2.5.1, 5.2.5.3 and 5.2.5.4(b) reinforces this.

Further, 5.3.4.1 states that DISCONNECT, not PROGRESS should be sent when 
sending a busy cause code with in band tones/announcements. 

Peter