Potential new asterisk installation


I look after a company (in an IT sense) that is moving premises into a building that has no existing infrastructure. I need to arrange structured cabling and a phone system for them and am thinking that perhaps this could be my excuse to getting some experience of Asterisk.

The setup is something like this -
ISDN30 (E1) into the building (use however many channels are needed).
12 Desktop user telephones
2 Analog lines (for Fax machines/modem)

The areas I would appreciate some help with are -
What cards to get for the PC that will run Asterisk.
What phones to get.

Is this something that I should be taking on on my own ?

Any advice is greatly appreciated.

That sounds like an idea sized project to start off with to me. See below for configs:

  1. PC system - Get one with a really good PSU as power quality is vital.
  2. Use a Smoothing UPS - Not all UPS systems do really good power smoothing as well (put the system and PoE network switches through this)
  3. ISDN Card - If you can go for a better quality card with onboard echo cancellation. This will produce the highest quality (i.e. Digium TE207P or TE212P). Be careful to order the card with the correct voltage for your PCI bus.
  4. Go for decent quality phones from someone line Aastra or Snom.
  5. For the analogue connections go for something like the Sipura SPA-2000 and not analogue cards in the system.

Hope this helps.

Can the analog lines not be pulled from the ISDN30 - or are there reasons why this isn’t preferred ?

I think he is saying pull he analog lines from the isdn30 and then route them via SIP to the sipura ATAs. I’d try to avoid this though, because if you can keep your call off SIP then faxes will probably be more reliable. I’d buy a TDM400 board with an FXS port or two and use that for faxing. That way, the fax audio is kept in the TDM world so packet loss / jitter won’t be an option.

agree that you need a good quality PSU and an ONLINE ups (they are pricier than passive/offline UPSs). Online means it’s always converting the power flow, not that it has a data port.

AAstra and SNOM are good phones. Set them up using the remote provisioning / massdeployment features and TFTP. Set up your DHCP server to provide TFTP info- that way you just add the files for the phone’s MAC address, and plug the phone in. It will then configure itself.

Use a good power over ethernet switch. Netgear makes a few that won’t break your budget. I’ve used the FS726tp (24 ports, 12 of them powered, 2 gigabit uplinks with fiber module slots, managed) and it’s a good deal for $300.

Thanks - that’s great - certainly enough information to get me going :smile:


on a similar project, I decided to get rid of the fax machine, rather than requiring an ATA
There is, instead, a printer/scanner/copier with scan-to-email function, so to send a fax one has to key the number into one of address or subject (we use subject).
The device happens to have a much better feeder than the fax machine…
Incoming faxes print on this device as well
I use hylafax and asterisk together, sharing an active card (AVM B1,C2,C4 type)


So my shopping list is as follows - does this cover it ? (how about any leads necessary to connect the Digum cards ?)

Phone System
ISDN30 line into Comms Room (under the stairs in Priory)
PC for PBX - good PSU PCI Bus
Digium TE207P/TE212P - Interface to ISDN30
Digium TDM40B - for fax/modem
Uninterruptable Power Supply with smoothing
Power Over Ethernet Switch
10 Desktop Phones - Aastra or SOMM

Patch Cabinet and crone strips (should be supplied by cabling installer)
Cat 5e Cabling to all points

Shelf for holding existing server (PBX will be rack mount)

Ok - can anyone suggest alternative cards ? This has gone way over budget :neutral_face:

the two cards worth a damn are digium and sangoma. remember with the tdm400 you only need one FXS port, the rest can be blank for now which saves a little…

ah, we’re in the grey area where Asterisk meets the smaller key systems. what is your budget ?

you could save money by using a smaller server, soft phones, etc, but will your user satisfaction be as great as with a new LG system for example ? it’s a tough one, but something every Asterisk installer is going to face at this number of users.

I don’t really have a budget as such - just getting it approved is harder the higher it is :smile:

Is there a recommended UK supplier ?

Can I skimp and not get echo cancellation cards ? Is the difference worth it ?

i’m in the UK and i’ve been getting good deals from voipon.co.uk

i’ve never bothered with hardware echo can on single span PRI installs, but i’ve always used the Sangoma A101u card and haven’t had a problem with echo. YMMV !!

So, assuming I end up with PCIx based machine -

1 * Sangoma A200 FXO FXS Analogue Card PCIx
1 * Sangoma A102 PCIx PRI ISDN Card

Should do me ? (and much nicer price :smile: )

if you’re going to use the A200, i would check the quality of your lines beforehand. too long, too noisy and you might start to wish you’d added the GBP200 on for echo can.

having said that, on a good line, there’s not much between the Sangoma and Digium cards … except maybe the better CID and answer supervision on the Sangomas.

Ok - thanks for the help - I really appreciate it.

You don’t fancy building this do you ? :wink:

if i could get away with only working with Asterisk systems i would !! if you need on or off-site help let me know.

I’ve installed this setup today and am having trouble getting the sangoma card to talk to BT - am getting a Line Code Violation and Far End Block Errors.

Does anyone have the 102d card working and care to share their config ?