RE: Congestion in M3UA/SUA and the use of the SCON

Brian,

I was under the impression that we were trying to make the layers about
SUA unaware that they are running over IP.  My ASP today does not
require knowledge of point codes.  And if SCON supported "source
address", the SG could properly implement the SSC procedures according
to the ITU specifications.  The ASP only needs to know it's calling
address (which may not contain a PC).  Because of your requirement
below, it is putting an additional and completely unneccessary
requirement on the ASP.  

Clearly you and I either disagree on this issue or we are failing to be
able to get our point across to each other. I will propose alternate
text for SUA relating to the SCON messsage.  I realize that you don't
feel this is necessary however it may be that others in the SIGTRAN list
feel otherwise.

Regards,
Lincoln

-----Original Message-----
From: Brian F. G. Bidulock [mailto:[email protected]] 
Sent: Monday, October 10, 2005 5:21 PM
To: Haresign Lincoln
Cc: Tolga Asveren; [email protected]
Subject: Re: [Sigtran] Congestion in M3UA/SUA and the use of the SCON

Haresign,

Haresign Lincoln wrote:
(Mon, 10 Oct 2005 14:38:13)
> Brian,
> 
> When talking about SUA, GTT can be performed in the SG.  However, 
> there is no requirement to modify the called address to PC/SSN.  In 
> some architectures, there is absolutely no need to know the PC/SSN if 
> you are working strictly with GTs.  And in some architectures, this 
> certainly simplies the provisioning.  Where does it say otherwise in 
> any requirement (SS7 or SIGTRAN)?
> 
> There is no need to perform GTT in an ASP.
> 
> I'm not sure where the disconnect is.  I'm quoting from the RFCs.  
> 
> The RFC says:
> 
> 1) An ASP can send an SCON to a SG.
> 
> 2) When an ASP talks to an SG, it does not need to know it's point
code.
> It's not a required parameter in dynamic registration.  It's not a 
> required parameter in the CL messages.

An AS does not need to know its point code to receive messages.
However, if SUA at th ASP is going to take responsibility for SCCP
congestion procedures, it needs to know which SCCP it is signalling
congestion for, and the instance of SCCP is identified by the MTP-SAP
which includes the point code.  This is nicely reflected in the fact
that the Affected Point Code is mandatory in the SCON if it is sent from
ASP to SG.

Sending SCON is optional.  If your ASP doesn't know its point code,
simply don't send SCON from ASP to SG.

--brian


--
Brian F. G. Bidulock
[email protected]
http://www.openss7.org/