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

[John Todd]

At 1:20 AM -0700 on 4/25/04, Tom wrote:
>On Sat, 24 Apr 2004, John Todd wrote:
>
>...
>>  My rule of thumb has been 100 G.729 channels for a dual 3.0ghz Xeon
>>  machine.  Cost: around $42 per channel (I buy SCSI systems with RAID,
>>  and that includes the $10 charge for the G.729 license.)  Your
>>  mileage may vary in both performance and price.  Cost for an
>>  AS5300-style solution: around $110 per channel, and that's on the
>...
>
>   I'm very interesting in a good per channel price, but $42 vs. $110 does
>not seem to be comparing apples to apples.  You say the Asterisk system is
>$4200 (100 x $42), less the $1000 for the G.729a license (100 x $10),
>which works out to $3200 for hardware.  A Digium quad T1 card is about
>$1500, meaning the server is around $1700?  Can you actually get a dual
>Zeon 3Ghz with SCSI and RAID for $1700?  I assuming that you have at least
>a GB of RAM installed, possibly more for 100 sessions.
>
>   Now a Cisco HDV-2T1-48 card is $3500, with dual T1s and loaded with DSP
>daughtercards.  That works out to $76/channel, and you need a free NM port
>on a Cisco router to install it into.  It is certainly more expensive than
>your $42/channel Asterisk setup, but for small sites is possibly less than
>a Cisco AA5300, especially if you can install it into an existing router.
>
>Tom

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.)

   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.

JT