Sangoma D100 Transcoding Cards

[bmorrison]

Greetings,

I was talking with my voip provider and an interesting question came up regarding the Sangoma D100 cards, vicidial and G729:

Assuming that all trunks and sip.conf are disallow=all and allow=g729, and assuming that there are .g729 versions of all audio files including the survey broadcast message, voicemail.conf is g729, and there is *no* ADM...

Would asterisk only use the D100 for the meetme conferences?

[williamconley]

i believe that the D100 is used for transcoding to/from, but the meetme rooms are used for bridging.

so the answer is "no" it would never use the D100 for meetme rooms, but if all calls are D100 it would use as many of the D100 channels as it can for transcoding.

but i'm guessing.

have you tested? can you monitor D100 use in asterisk or in the OS?

[mflorell]

Actually, the answer is Yes.

We have been testing the D100 cards and they are great, but with Asterisk meetme everything needs to be translated down to slin for mixing, so every G729 channel going into a meetme room would use a license to do G729.

[bmorrison]

Thanks for replying!

Doesn't a meetme room have to transcode the compressed audio (be it g729 or whatever) into slin to mix the audio and then transcode everything again to send along to the meetme participants? Isn't that one of the reasons why an agent with g729 on their softphone use pass through the dialer (as far as I understand)?

To answer your question I'm exploring getting a D100.

If the D100 won't be used to transcode the meetme conferences, then what good is it for?

[bmorrison]

Ah, posted that right before I asked about meetme rooms. mflorell to the rescue.

[mflorell]

We have had a very good experience with the D100 cards that we have been testing. In our production tests the card cuts the load on a system doing heavy G729 transcoding in half.

Also, there are a lot of configuration options for the card which allows you to do many different codec translations as well as octasic audio filtering. It is much much better than the Digium transcoding card, and available in quadruple the channel capacity too.

[bmorrison]

Actually, the answer is Yes.

We have been testing the D100 cards and they are great, but with Asterisk meetme everything needs to be translated down to slin for mixing, so every G729 channel going into a meetme room would use a license to do G729.

Okay, so the million dollar question: With the D100-30 (the 30 channel version) would you be able to support 15 meetme rooms (one agent and one caller) or 30?

[williamconley]

ok, but i have a question ...

at $900 for a 60 channel card what would be the advantage over, say, a $900 Xeon box dedicated to the same purpose between the Vicidial server and the net doing the same thing?
(dedicated pure asterisk on a 64 bit OS providing g729 conversion to all the "inside the room" boxes", instead of just the one that the D100 is installed in).

I mean, this would change all the inbound audio to ULAW so transcoding would be virtually without cost on the vicidial server.

Is the sound quality improved? or is there some other advantage?

I see the reaction to having a "dedicated" translation/call routing server all the time, noone wants to spend the cash on a box that's dedicated to such a purpose (well, few are, unless they've done a lot of research). But spending cash on a card to go in the box, they'll do without hesitation even though that card is now a limiting factor requiring the calls to go to that hardware.

[williamconley]

Actually, the answer is Yes.

We have been testing the D100 cards and they are great, but with Asterisk meetme everything needs to be translated down to slin for mixing, so every G729 channel going into a meetme room would use a license to do G729.

Okay, so the million dollar question: With the D100-30 (the 30 channel version) would you be able to support 15 meetme rooms (one agent and one caller) or 30?

are the agents on ulaw or g729? and how many calls are being generated FOR each agent?

[bmorrison]

ok, but i have a question ...

at $900 for a 60 channel card what would be the advantage over, say, a $900 Xeon box dedicated to the same purpose between the Vicidial server and the net doing the same thing?
(dedicated pure asterisk on a 64 bit OS providing g729 conversion to all the "inside the room" boxes", instead of just the one that the D100 is installed in).

I mean, this would change all the inbound audio to ULAW so transcoding would be virtually without cost on the vicidial server.

Is the sound quality improved? or is there some other advantage?

I see the reaction to having a "dedicated" translation/call routing server all the time, noone wants to spend the cash on a box that's dedicated to such a purpose (well, few are, unless they've done a lot of research). But spending cash on a card to go in the box, they'll do without hesitation even though that card is now a limiting factor requiring the calls to go to that hardware.

Well, at least for us, we have to pay colo rent.

[mflorell]

We have only tested the 480 call version of the D100 cards, a transcoding capacity that you can't easily duplicate reliably, or with as high audio quality, on a single server.

[bmorrison]

We have only tested the 480 call version of the D100 cards, a transcoding capacity that you can't easily duplicate reliably, or with as high audio quality, on a single server.

Gotcha. I imagine not! How many G729 licenses does the D100 use per meetme room?

[williamconley]

g729 licensing is "per channel" not "per meetme room"

since one meetme room may have many entries, with different codecs, that's not something easily stated

if the agent is ulaw and the prospect is g729, that's ONE. if the agent then "brings in" a 3rd party (prospect's wife/decision maker? verification recorder for fulfillment center? whatever) if that call is also g729, then that's TWO

[bmorrison]

We have been testing the D100 cards and they are great, but with Asterisk meetme everything needs to be translated down to slin for mixing, so every G729 channel going into a meetme room would use a license to do G729.

Oh wait you said right here that each channel needs a license. I need to calm down.

Thanks!

[williamconley]

what bugs me, though, is that the D100 "specs" imply that g729 licensing is "included" after a fashion. but i think what they mean is that this particular device does not need ANOTHER g729 license.

[mflorell]

You do not need to pay any additional licensing fees to use the included G729 channels of capacity on the D100 card, they are included already in the cost of the card.

[williamconley]

so the $900 card includes $600 worth of g729 licensing? the box it is on does not need to have sep g729 licenses (unless it bypasses the card to use g729 independently)?

[bmorrison]

From their website:

All codecs are fully indemnified; no additional licensing is required for their use².

http://www.sangoma.com/products/hardwar ... oding.html

[williamconley]

yep, i read that, too. but "indemnified" is not the same as "this device includes 60 g729 licenses". The question is whether not purchasing g729 licenses and then installing this device will REMOVE the need to purchase those licenses. Cuz that's some cash.

[bmorrison]

Well it wouldn't be of much utility if we had to purchase licenses on top of the card. I read it as a D100-30 (for example) having 30 g729 licenses.

[williamconley]

cool reading. but will it WORK without purchasing/installing g729?

[mflorell]

Yes, it will work without loading any g729 asterisk software-only transcoding modules. Asterisk is built with the ability to off-load codec translation through a module to an outside resource like a card or transcoding server. That's how it works.

[bmorrison]

Yes, it will work without loading any g729 asterisk software-only transcoding modules. Asterisk is built with the ability to off-load codec translation through a module to an outside resource like a card or transcoding server. That's how it works.

So my 'cool reading' is correct then? Cool!

I'm going to order one of these suckers now. Thanks!

[williamconley]

watch your pricing.

the 60 and 120 (and up) seem to be very close to the 30 price

and the ability to handle LOTS of calls generally stems from having them all at a low cpu cost (ie: if the g729 transcoding is offloaded, you may be able to handle a LOT more calls than you think)

not to mention what happens when you upgrade your server and realize it can handle over 100 calls easily ... but you have a 30 card.

thanks matt, that was a great conversation.

[mcargile]

One thing to watch out for when using one of these cards is to make sure it is only offloading the codec translations you need it to. By default it will offload all of the translations. This is a problem because as Matt said meetme uses slin. So if you agents are using ulaw for their phone connections and your carrier is using g729, by default the card will be offloading both the agent and the carrier translations to it. There are several other things that might be going into the meetme conferences as well, all of which are potentially using a translation path. Once you go past the capacity of your card it will start hanging up on the calls rather than using the internal asterisk codec translators. By limiting it to say g729 you only have to worry about the calls going to the carrier being offloaded to the card.