[asterisk-users] Redundant PSTN PRI Gateways using Asterisk

[Steve Totaro]

On Tue, Sep 2, 2008 at 8:17 AM, Karl Fife
<asterisk-users at kfife.mailworks.org> wrote:
>
> On Mon, 1 Sep 2008 22:01:19 -0400, "Michael Melia Jr." said:
>>
>> I am looking to implement Asterisk in front of the legacy PBX as the new
>> gateway to the PSTN for the company in an effort to begin a slow
>> transition to VoIP.  While I am familiar with Asterisk when it comes to
>> implementing it as a single box solution for PRI, SIP, voicemail, IVR,
>> etc, I get a little confused when you start to separate the functions to
>> different boxes for redundancy and scalability.
>>
>
> We're doing something similar, except that we have only 1 PRI.  I too am
> partially in new waters with this project, but we've chosen to buy a
> RedFone box instead of a complex assortment of PRI cards between MAIN
> and FAILOVER and LEGACY PBX's.  We like the choice because it's simple,
> highly reliable and gives us lots of flexibility and failover options
> (available).  For example:
>
> 1 - It means we don't have to any PRI cards for the asterisk servers
> themselves--the redfone box wraps the TDM in ethernet frames.  The
> Asterisk boxes need no hardware other than their own ethernet cards.
> The Redfone box translates the TDM to TDM over Ethernet (TDMoE).  Now we
> can do any *logical* routing we want between Ast1, Ast2 and Legacy
> without having to establish *physical* routes and interfaces.
> 2 - The RedFone box has the PRI interface(s) from the Telco, AND to the
> legacy PBX.  The legacy PBX remains essentially unchanged, except that
> RF routes the traffic to Ast1 (Ast2 if Ast1 is down), and Asterisk can
> decide which call tasks it wants to handle, and which it will route BACK
> to the legacy PBX.  If we want migrate a number, service, mailbox, IVR
> etc AWAY from the Legacy PBX, we do so easily with a tiny tweak of the
> dialplan.  If we move something from away from the legacy system, and it
> turns out to have a problem, bug, etc. (not that my dialplans EVER have
> problems, but I'm just speaking hypothetically :-) ), I can just send it
> back with the same tiny dialplan tweak.
> 3 - In an unlikely double-failover scenario, I can leave all of my
> legacy IVR trees etc intact on the legacy PBX.  If both Asterisk servers
> are down, the customer is routed to the old system.  The customer may
> wonder why they're hearing the OLD voiceover artist, instead of the NEW
> voiceover artist but at least the call gets handled :-)
>
> This is just another tool to consider.  I would be able to report in
> more detail but at this time but it's a work in progress.  If anyone has
> a RedFone solution in place and would care to report on (from the
> trenches) I'd be interested in hearing your experience.
>
> -Karl
>

I will be deploying several Redfone devices this month for the reasons
you outlined above.  The device is new to me also, maybe we can
compare notes.

Redfone has a great guarantee, their presence at last year's Astricon,
and positive things I have seen here and there lead me to believe that
they are a no brainer for this functionality.

Thanks,
Steve Totaro



Thanks,
Steve Totaro