PBX options - SIP

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quik

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Hey guys

We're in the process of acquiring a 30 channel SIP trunk, and we need to source a PBX.

First consideration is whether we should go with a software or hardware based system. I'm leaning towards software based.

I'd like to get some opinions on the various options, whether it be hardware or software based, one of the most important considerations for us would be billing capabilities. It's an office complex with multiple companies so it's important that we can give each office a statement at the end of the month. Every time I mention this to an Asterisk provider, it's like a white elephant walks into the room. Why is that? :p

Another consideration would be the learning curve. We're new to the PBX/VOIP scene, so whatever we decide on, it would be nice if we can get it up and running in a day or two.

I've done a bit of reading up on different products available including 3CX, Callbutler, Asterisk and MS Communications Server (Is that even a PBX system?). Going to a demo on Mitel and NEC hardware based systems tomorrow.

Any resources or advice would be much appreciated.
 
First let me warn you to stay away from VOIP. It does not work, this is from experience. Internal IP works fine but external calls via internet do NOT work for business. It is too erratic and not guaranteed QOS.
Most PBX's have the software or ability to have cost centres assigned to various departments or people.
 
Mitel is a fairly good system, I'm running 2 mitels Sandton and CTN.

ditto on internet calls, I have site to site calls between the pbx's, voip over leased lines is best, internet call over diginet are alright if you can police your traffic properly.

I don't recommend voip over adsl as it's not reliable enough to ensure the quality remains stable.

D
 
Yes agreed, however Mitel is expensive, the Samsung systems we sell are very good and are all rack mounted sever based systems. VOIP over Diginet is the only way to do it.
 
marine1 said:
First let me warn you to stay away from VOIP. It does not work, this is from experience. Internal IP works fine but external calls via internet do NOT work for business. It is too erratic and not guaranteed QOS.
Most PBX's have the software or ability to have cost centres assigned to various departments or people.
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We're getting 30 SIP channels over CDMA, which the salesman gauranteed me would give us the same quality voice calls as if it were over fibre. It also comes with the same SLA as the fibre and diginet services. Would that be sufficient?
 
quik said:
We're getting 30 SIP channels over CDMA, which the salesman gauranteed me would give us the same quality voice calls as if it were over fibre. It also comes with the same SLA as the fibre and diginet services. Would that be sufficient?
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I dont believe that CDMA, well hold on no actually Neotel run over CDMA so.....
I still think Fibre is the best quality and also reliable. Who is the CDMA through?
Also what system?
Just explain to me....why do you want to use SIP "channels" what are you trying to do?
SAMSUNG uses SIP as well.
 
marine1 said:
I dont believe that CDMA, well hold on no actually Neotel run over CDMA so.....
I still think Fibre is the best quality and also reliable. Who is the CDMA through?
Also what system?
Just explain to me....why do you want to use SIP "channels" what are you trying to do?
SAMSUNG uses SIP as well.
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The CDMA is through Neotel, it was either them or Telkom, so my choice was easy.
I don't know what system they use, afaik they terminate their equipment on our premises where we plug it into our PBX. Fibre is not an option in our area yet.
They gave us the choice between SIP and PRI/BRI, can't remember which one, but once again the sales manager said there would be no difference in quality between the two, and they also provide the same SLA with the SIP trunk.
 
Ok makes sense now, yes Neotel use the CDMA and it connects to the PBX via analogue ports. The device sits on the wall and is wireless. It then connects from the bottom of the device much the same as a premi cell, into the PBX, into the PBX's analogue trunk ports, exactly the same as the normal Telkom lines.
There would be a difference between PRI/BRI - Analogue.
How many lines have you applied for?
Not really sure what he means by SIP - Session initiated protocol.
why would you need it?
Wouldnt SIP be used for say a cellphone? Neotel does offer IP based SIP
 
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marine1 said:
Ok makes sense now, yes Neotel use the CDMA and it connects to the PBX via analogue ports. The device sits on the wall and is wireless. It then connects from the bottom of the device much the same as a premi cell, into the PBX, into the PBX's analogue trunk ports, exactly the same as the normal Telkom lines.
There would be a difference between PRI/BRI - Analogue.
How many lines have you applied for?
Not really sure what he means by SIP - Session initiated protocol.
why would you need it?
Wouldnt SIP be used for say a cellphone? Neotel does offer IP based SIP
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We have applied for 30 lines. Is SIP/BRI/PRI the protocol they use to carry the voice over their network?

One of the reasons why we opted for SIP is that they said it is much easier to add additional lines to a SIP based system than to a BRI/PRI based system. You can for example add an additional 10 lines to the system within a day whereas they would have to install a whole 30 line BRI/PRI trunk if we required additional lines.

Am I missing something here?
 
No you would be correct although I dont think I would refer to the lines as SIP but rather analogue trunks and yes that would make sense what they have told you. Adding additional Neotel lines does not take long where as a PRI /BRI could take time.
How many extensions you going to use?
 
Just spoke to the service consultant, and he says everything runs on IP based SIP.

Their equipment terminates with an ethernet port which we just connect to our PBX.
 
marine1 said:
No you would be correct although I dont think I would refer to the lines as SIP but rather analogue trunks and yes that would make sense what they have told you. Adding additional Neotel lines does not take long where as a PRI /BRI could take time.
How many extensions you going to use?
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We are a bunch of companies sharing the service, so I don't know how many extentions we're going to require yet.

Don't think it really matters though, adding extensions should be childsplay. Just another ethernet point and IP Phone. 30 lines and 200 phone numbers should last us a while.
 
If you can find a solid Asterisk provider go with it. The flexibility you get with Asterisk over a traditional PBX is well worth it. The caution I can throw in here is just because it can run on PC hardware does not mean you should. If you want reliability on your PBX then buy server class hardware with RAID and nice fast SAS discs (It will still be cheaper than a traditional PBX). Same thing with phones. Polycom and Snom are very good. The cheaper stuff like budgetone I have come across at sites are shockingly bad.

The choice between a pure VoIP (SIP, IAX) or fixed line (PRI/BRI) can be difficult. The Neotel setup comes with a dedicated data line and thus your quality should be good. A lot of people offer you a SIP service but then let you run that over ADSL which can prove unreliable and cause bad quality.

If you want a no nonsense will always work option then PRI (from Telkom) is a good choice. It hardly ever dies and offers consistent quality. I have however heard good things about Neotel's SIP offering. Neotel in fact rate their PRI and SIP service as the same (essentially it runs over the same backbone).

Going with SIP does save you from buying a PRI card for your PBX, but with Asterisk it is advisable to have at least one voice card in the machine to provide clocking (a cheap analogue card from Digium will do). Otherwise you can having timing slips which with cause quality problems.

For billing go look at Aspivia. It's not free but they have a really top notch billing system and it's worth the money.
 
morkhans said:
If you can find a solid Asterisk provider go with it. The flexibility you get with Asterisk over a traditional PBX is well worth it. The caution I can throw in here is just because it can run on PC hardware does not mean you should. If you want reliability on your PBX then buy server class hardware with RAID and nice fast SAS discs (It will still be cheaper than a traditional PBX). Same thing with phones. Polycom and Snom are very good. The cheaper stuff like budgetone I have come across at sites are shockingly bad.
T
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Lol, thanks for the heads up, was actually looking at getting the Grandstream Budgetone phones because the cost is so much lower than the SNOM. What makes the budgetone devices so bad?

RAID and Online UPS's is also high on my list of importance. Do you perhaps have an idea of the hardware requirements for a soft PBX?

The choice between a pure VoIP (SIP, IAX) or fixed line (PRI/BRI) can be difficult. The Neotel setup comes with a dedicated data line and thus your quality should be good. A lot of people offer you a SIP service but then let you run that over ADSL which can prove unreliable and cause bad quality.
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Another provider actually wanted us to go the VOIP over ADSL route, and my stomach started turning. I'd have people on my back permanently. :(

If you want a no nonsense will always work option then PRI (from Telkom) is a good choice. It hardly ever dies and offers consistent quality. I have however heard good things about Neotel's SIP offering. Neotel in fact rate their PRI and SIP service as the same (essentially it runs over the same backbone).
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Frankly, Telkom had the last ten years to make an impression, and they dissapointed every time. Their equipment, PBX sollution and monthly costs are all much more expensive than Neotel, so the choice was easy. I'd prefer to choose and manage the PBX myself in any case. Neotel actually gives us the same SLA on SIP over CDMA than they would with PRI over Fibre, not bad!

Going with SIP does save you from buying a PRI card for your PBX, but with Asterisk it is advisable to have at least one voice card in the machine to provide clocking (a cheap analogue card from Digium will do). Otherwise you can having timing slips which with cause quality problems.
Click to expand...

I've been considering 3CX as well, quite expensive but the learning curve seems much less than with Asterisk.

I'd need an experienced Asterisk technician if I go that route, any volunteers? I'm definately leaning towards software based PBX though as I think that's the future in this market. Most certainly not going with anything proprietary.

For billing go look at Aspivia. It's not free but they have a really top notch billing system and it's worth the money.
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The white elephant once again :p Does asterisk have built in billing or a billing add-on? If so, is it any good. It just seems to me like they're trying to milk money out of the whole billing issue.
 
Marine1: I find it interesting that you attack VoIP given that you don't even know what SIP is. It's only the most widely used standard for VoIP signalling! Have you considered that your lack of knowlege regarding VoIP may, at least in part, have led to poor implementation and a disappointing service experience?

Not all providers are the same, not all networks are the same and not all VoIP is the same. Yes, VoIP over the public internet can vary in quality. Different aspects affect this. e.g. local or foreign soft-switch, connectivity of the provider, quality of devices used on both the customer side and provider side, level of interconnection of the provider.

I have customers with upwards of R50,000 per month worth of phone calls running over VoIP. At that level, if the quality was not good, I'm pretty certain they would move elsewhere. Interestingly, one such customer actually said "thank you for the great service" over the phone today. Of course, that was a professional installation using tried-and-tested technologies and properly set up from the start. ADSL was used, but supplemented with wireless (for backup).

Quik: the Neotel service you refer to is carried using VoIP (SIP) up to your premises in any case. Fibre is generally better than a wireless technology like W-CDMA, however, fibre can get damaged too and for the type of service you're purchasing (which does not require huge amounts of capacity), the cost of running fibre where it doesn't already exist is prohibitive. If you opt for any other interface (e.g. ISDN PRI), they simply convert from SIP to PRI using a gateway device at your premises. There is a huge cost advantage (in terms of the switchboard) if you connect via SIP and it is scalable via software from 1 to thousands of channels where a PRI interface is fixed at 30 channels.

Regarding switchboards, there are a number of quality brands out there. Keep in mind that a number of the newer IP-based switchboards are empowering people to manage their own switchboards rather than necessitating the cost and inconvenience of calling out a consultant every time you want a change.
 
Sorry, just seen that last post.

Avoid Grandstream budgetones like the plague. If you want a good, cheap IP phone, look at the ATcom AT-530. Same money, infinitely better.

But for a business environment where good comms are essential I'd always recommend spending a bit more and getting great IP phones. The Snoms are excellent phones, as are the LinkSys.

I use a LinkSys myself, but have installations of Snom and LinkSys at many happy clients.

The Polycoms are quite costly by comparison.
 
quik said:
Lol, thanks for the heads up, was actually looking at getting the Grandstream Budgetone phones because the cost is so much lower than the SNOM. What makes the budgetone devices so bad?
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Static, terrible audio quality and then eventually they just fail. The Snom's are really good quality easy to setup and mass deploy. The entry level 300's even support PoE. I did play with the Linksys phones which were really good, but the entry level ones which were cheaper than the Snom 300's did not have a cascading network jack so you needed 2 points per desk. So when you add the extra point you have paid for a Snom (which does cascade).

quik said:
RAID and Online UPS's is also high on my list of importance. Do you perhaps have an idea of the hardware requirements for a soft PBX?
Click to expand...
We take a rather conservative approach: Dual quad core server we'll scale to 120 concurrent calls with call recording. You can probably push that up to 200, but with voice too much disc or CPU overhead causes audio problems. Call recording does add a substantial overhead to the disk performance so watch out for that. We like to see the box not working too hard :)

quik said:
Frankly, Telkom had the last ten years to make an impression, and they dissapointed every time. Their equipment, PBX sollution and monthly costs are all much more expensive than Neotel, so the choice was easy. I'd prefer to choose and manage the PBX myself in any case. Neotel actually gives us the same SLA on SIP over CDMA than they would with PRI over Fibre, not bad!
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Good riddance then :)

quik said:
I've been considering 3CX as well, quite expensive but the learning curve seems much less than with Asterisk.

I'd need an experienced Asterisk technician if I go that route, any volunteers? I'm definately leaning towards software based PBX though as I think that's the future in this market. Most certainly not going with anything proprietary.
Click to expand...

I am not familiar with 3CX. Asterisk with FreePBX slapped on top of it does not require too much know how for the day to day tasks. Where many flyby night Asterisk vendors get into trouble is when the OS starts running into problems or the machine does not perform. They lack the Linux skills to troubleshoot it properly and eventually you find yourself buying a whole new box with a fresh copy of trixbox to "solve everything".

The company I work for does specialise in Asterisk, but we are Cape Town based at the moment. We can do remote support, but it can get tricky when you need eyes and hands onsite. You can PM me if you like for more info (I'm not here to punt our services).

quik said:
The white elephant once again :p Does asterisk have built in billing or a billing add-on? If so, is it any good. It just seems to me like they're trying to milk money out of the whole billing issue.
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Asterisk does CDR, but not billing (so the call information is there you just have to cost it yourself). Unfortunately I have not come across a suitable free solution. We use Aspivia with Asterisk and it works really well. From a support point of view Aspivia is a set and forget for us. They have automated reports you can mail to the managers of the various departments and even individuals. The monthly spend is quickly recovered in unnecessary calls that are not made.
 
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