[Asterisk-Users] Re: Hardware for handling large call volume

[Tom]

On Sun, 25 Apr 2004, John Todd wrote:

> Tom -
>    You're right - I forgot about the 4-port card.  The calculations
> sitting in the other page of my screen from which I took those
> numbers were for my spare system.  In any case, let's say that's an
> additional $15 per channel, so $57 per port.
>
>    Your side of the equation isn't quite right, either.  Unless you
> happen to have a "spare" Cisco chassis hanging around, you're not
> going to be paying $3500 for 2 PRI's.  It's more like $5500 for an
> AS5300 with two PRI's, and that's a good price on used gear (vs.
> typical price on new gear for the Asterisk server.)

  You don't need a spare chassis, just a spare Network Module (NM) slot.
HDV-2T-48 cards aren't for the Cisco AS platforms.  They can be installed
a Cisco 2600, 3600, 3700 routers only, which many people have already.
Some people think that VoIP on Cisco means that you must have a Cisco AS
of some sort.  Cisco makes voice cards for many routers.  You'd be shocked
on how cheap a PA-VXC card is for a Cisco 7200/7500 platform:  I've seen
them go for $2500 on eBay.  The only thing a Cisco AS does, that the other
Cisco voice cards don't, is modem support.  Which is something that a
Digium card can't either, BTW, but I don't think anyone really cares about
that anymore.

>    In any case, my argument still stands.  Generic computing platforms
> are dropping in price far more quickly than DSP-based platforms.
> Let's do this price comparison again in a year.  Audio transcoding
> can and will become a process that is handled by the primary CPU of a
> system at all but the most dense locations in the network.  I'm a big
> fan of stupid networks.

  I see this arguement on specialized versus generic come up from time to
time.  Take a look at what happened to the video card market.  DSPs are
just simplified, purpose built CPUs.  DSPs are just about adding more
processing power in addition to the CPU, just like GPUs.

  The unit cost of DSPs is not very high.  VoIP Gateways are expensive
though, but competition is starting to change that, especially on the low
end.  I can now get a four port FXO Ovislink gatway for $450.  In
comparison, four Diginum single port FXO cards are $400 alone.  As volume
of VoIP Gateways shipped increases, prices will drop.  Now of course, I
hope that Digium cards will drop in price too, as volume increases.

> JT

Tom