[Asterisk-Dev] need some suggestions

[Mike M]

On Sun, Nov 28, 2004 at 03:24:42AM -0600, Rehan Ahmed wrote:
> Dear Michael,
> 
> pardon my question, but do u know any one who has implimented ss7 on 
> asterisk yet, at a reasonable cost.

I do not know of any "SS7 on Asterisk" implementations.  If SS7 on * is
truly desired, then purchasing a card solution with embedded MTP2 is the
way to go.  The cost will be several thousand dollars per card.
Achieving path redundancy will be...not worth the effort.  Sharing the 
SS7 bandwidth with other * without redundancy increases the negative
impact on users when an SS7 failure does occur.  A 64 kb/s SS7 link
runnig at typical max load of 40% utilization will support 1200 calls
per minute.  If the * needs a reset, then 1200 or less customers will
be without service during the reset.  The SS7 network provider expects
operational stability from its connected links.

If the SS7 function is on a separate signal gateway that connects to *
over IP, then the s/g can serve n X * and be redundant.  This approach
saves on capital costs and operation costs, and raises reliability and
stability to accepted levels.

I do know of reasonably priced s/g that want to serve Asterisk but 
Asterisk is not ready to communicate with an s/g.  That's why I suggest the 
project below.  

The next step after B is to break the D channel and insert 
two s/g (shown in C).  The network application is shown in D.  
A-D shows the conversion of PRI FAS to PRI FAS over IP.  Step E is 
to develop PRI NFAS over IP.  Step F is to develop native ISUP over IP.
Somewhere along the path SCCP/TCAP based applications are integrated
(free call, billing number services, calling name delivery, special
routing services, SMS, etc.).

C)   phone---*----B channels---[     *     ]---phone
             |                   |       |
             +--D--[s/g]--SS7--[s/g]--D--+

D)   phone---*----IMT-------------------pstn
             |                           |
             +--D---------------[s/g]---SS7 network
> 
> I am setting up a new telco and need SS7 interface to itnerconnect 
> with the local provider
> 
> Rehan
> 
> 
> > On Sat, Nov 27, 2004 at 09:46:21AM +0500, Xenith Panacea wrote:
> > > I need some advice/suggestions for as to what should we work on.
> > > Something that is practical and beneficial not only for our degree
> > > work, but more importanlty which contributes to the * development.
> > 
> > Asterisk needs an IMT/SS7 interface.  I am advocating an approach
> > where a signal gateway interfaces the SS7 network and provides Q.931
> > signals (packets) over IP to Asterisk.  For * to take advantage of
> > this capability, it needs to expose its PRI FAS function to an IP
> > port.
> > 
> > Shown below, A is now.  B is after development.  Having B would
> > advance development significantly toward having SS7 based call setup 
> > on Asterisk.
> > 
> > Test:
> > 
> > A)   phone---*----PRI----*---phone
> > 
> > B)   phone---*----B channels----*---phone
> >              |                  |
> >              +----D channel-----+
> > -- 
> > Michael Mueller
> > _______________________________________________
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> 

-- 
Michael Mueller