Re: Upper boundary of Adaptation Layers

Ilie,

Ilie Glib wrote:                                                      (Tue, 10 Jan 2006 12:00:52)
> Hello Brian,
> 
> On 1/9/06, Brian F. G. Bidulock <[email protected]> wrote:
> > Ilie,
> >
> > Ilie Glib wrote:                                                      (Mon, 09 Jan 2006 17:21:57)
> > > Hello Brian,
> > >
> > > I can not agree with you that SUA enables applications to use IP
> > > addresses. Indeed Source and Destination addresses can contain IP
> > > addresses, but this is an implicit impact on the xxUA users rather
> > > than an explicit impact. Currently section "1.6.1.  Definition of the
> > > upper boundary" does not extend SS7 primitives. If this extension is
> > > wanted it shall be in the standard documents (RFCs).
> >
> > Don't be absurd.  1.6.1 says that the standard SCCP/SCCP-User primitives
> > are supported.
> 
> [Ilie] Therefore an implementation of SUA Layer in may not have any
> other primitives than SCCP/SCCP-User primitives. Is this correct?
> 
  
  Read on:

> >It does not say that nothing else is supported or
> > supportable.  It does not say that no other primitives shall be used.
> > It is just the list of intentionally supported primitives.
> >
> > There are, I hope you realize, more national protocol variants than just
> > ITU or ANSI.
> >
> > >
> > > Apropos Source and Destination addresses cannot contain hostnames.
> > > IMHO hostnames are much more usefull than IP addresses.
> > >
> > > If it is wanted that xxUA become a true standard the content of the
> > > upper boundary shall be defined down to the last bit.
> >
> > Actually, the upper boundary at the ASP is a local matter.  There are no
> > requirements placed on the boundary.  It certainly does not have to
> > specified to the bit.
> 
> [Ilie] This was just a poetical exaggeration.
> 
> I interpret your statement above, that it is an implementation matter
> whether other than  SCCP/SCCP-User primitives are introduced or not.
> By the way are there any standardized SCCP/SUA (M3UA) user
> applications/protocols that use other primitives that those mentioned
> in 1.6.1?
> I have not heard of any.
> My opinion is that it is not possible to standardize an xxUA-User
> /Application (which uses an extended  service as compared to
> SCCP/MTP3) without having the SUA/M3UA upper boundary well defined, at
> the level the ITU-T defines SCCP-User primitives, or alternatively
> this new standard of the application shall refine its lower boundary.
> Do you agree?
> 
> With the current definition of the xxUA upper boundary all User
> Applications will rely on the definitions in the SS7 (section 1.6.1 in
> the RFCs).
> If some vendors will implement extensions to the primitives in 1.6.1,
> those will be most probably due to internal system architecture.

I don't know what you mean by "rely on."  All SS7 stacks are vendor
specific.  The only thing an application can rely upon is the interface
provided by the vendor.

The closest to an application interface standard is the Network Provider
Interface (NPI) from UNIX International (OSI Work Group) [now OpenGroup],
which provides X.210 support for X.213 and can, therefore, be applied to
SCCP.

The NPI uses N_BIND_REQ/N_BIND_ACK instead of N-STATE Request/Indication,
and N_UDERR_IND/N_DISCON_IND instead of N-NOTICE and N-PCSTATE.  Q.713
even provides mapping of SCCP causes into X.213 causes so the OSI header
files for NPI are usable.

The other UAs have no API standard whatsoever.

--brian


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