I’m thinking about putting together an Asterisk based PBX for the company I work for (as opposed the hardware PBX they want me to install…yuck). Everything I’ve read so far deals with setting up IP calls, or IP calls + POTS calls. However, I want ONLY to use POTS for calls. We have 2 incoming phone lines, plus a DSL line that does internet and Fax. I would need to purchase an FXO card (Digium X100P?) for each incoming line, correct? I’m curious, though, how it connects to the 66 block. Our phone wiring is CAT-5, which allows us to connect a CAT-5 cable with two RJ-11 connectors from the wall to the phone to give each phone both incoming lines. Could I do the same thing with the Asterisk box to give it control over both lines? Would I then just need 1 connection (instead of the current 2) at each phone station? Then, adding an extension would be as simple as connecting another internal line to the 66 block, correct?
Also, are there any POTS only setup docs. for Asterisk?
As you can tell, I’m trying to figure out how all this phone jazz works. All of the sudden they want a PBX installed and I have to figure it out. Looks like Asterisk would work pretty well, though.
Hm, I jus realized that might be slightly convoluted.
I have two (2) incoming POTS lines.
I have 11 (need up to 18 or so) extensions.
How does the Asterisk box connect to the POTS lines, as in, does it have to be directly wired to the 66 block? I would need two (2) FXS ports on the Asterisk machine, correct? How do the extensions make use of the phone lines, then? Can they also just be wired to to the 66 block?
If someone has a link to a beginner guide to understanding this, I would surely appreciate it, so that I may get all my ducks in a row and make sure I completely understand how it all works before I start buying equipment and playing with things.
Yes, you would need an FXO port for each POTS line coming in. I would recommend staying away from the X100P, they are not very good cards, they are $20 for a reason. Get yourself a good TDM400P with two FXO modules on it.
The cards all have the RJ11 jacks on them, so you could plug one end into the card, and punch the other on the 66 block.
Since all the wiring to the desks is Cat 5, you could utilize it with IP phones, it would be easiest I would imagine. Otherwise you would need an FXS port for each phone in the wiring closet. The FXS port would connect a plain analogue telephone to asterisk.
I would use the cat5, put wall jacks by the desk, and a patch panel on the other, drop a switch in the closet and get IP phones.
Thanks a lot for the clarification. I just read on here that the X100P basically sucks. So, I’d be looking at a few TDM400P cards. I’d only need 2 FXO ports, but then for 11 phones, I’d need 11 FXS ports. Are there cards that ONLY have FXS ports?
I thought a bit about using IP phones, since we’re already wired with CAT-5, but I’m not sure if I could talk them into it. We’d need to up our DSL line (according to the online tests) to the 3Mb/sec line, and then I’d have to get a bunch of new IP phones. Could probably get this hardware PBX installed for about the same price…Although, that does sound soooo nice. We already have a patch panel with a bunch of unused ports, so I could get the wall jacks wired to the patch panel, and then just connect them to a bigger switch…and be ready to rock.
Would there be any benefits of keeping the POTS lines?
Thank you SO much.
[quote=“eric_f”]Hi
Yes, you would need an FXO port for each POTS line coming in. I would recommend staying away from the X100P, they are not very good cards, they are $20 for a reason. Get yourself a good TDM400P with two FXO modules on it.
The cards all have the RJ11 jacks on them, so you could plug one end into the card, and punch the other on the 66 block.
Since all the wiring to the desks is Cat 5, you could utilize it with IP phones, it would be easiest I would imagine. Otherwise you would need an FXS port for each phone in the wiring closet. The FXS port would connect a plain analogue telephone to asterisk.
I would use the cat5, put wall jacks by the desk, and a patch panel on the other, drop a switch in the closet and get IP phones.
what you can do, and what I mainly do, is run IP inside the office, and use asterisk to connect the IP phones to the POTS. So you would have IP phones on the desks, all connected up to asterisk over the cat5, and still have the TDM card with two FXO ports connected to the POTS. So no need to up the DSL service.
My setup is like i said much the same, i have roughly 20 IP phones, connected to my asterisk box, asterisk has a TDM400P with 4 FXO modules. That allows me to have 4 lines from my local telco, and then when a call comes in do with it what i please. I have one box running 3 businesses, so depending on which POTS line the call comes in on, it gets directed to different phones. I also have a voip provider for my long distance calling.
I have a few different IP phones, Polycom IP 301, Aastra 9133i and Grandstream budetone 101. Overall I like my polycom’s the best, hard to setup initially, (config is confusing as all hell) but once you understand they are a treat to work with.
You can keep it all analog as well. For that you have two choices
a) get a TDM2400P with 1 FXO Module (4 ports) and 3 FXS Modules (12 ports) and still have 2 module slots left for expansion of FXS or FXO in the future
b) get a T1 card (TE120P) and a channel bank (I suggest the RHINO box - it works well and the support is great)
I would not suggest putting more than 1 card in a machine as that will usually cause IRQ conflicts and voice quality and server stablity may suffer. Option a is cheaper but will only expand by 8 more ports than you need currently. Option b is more expensive but you could get a 2 port T1 card and add a second channel bank if necessary.
My suggestion would be to go with option a for all existing phones and for new phones and over time add SIP phones. It will end up being a better and cheaper installation.
I would also suggest that you buy\download the book “Asterisk: The Future of Telephony 2nd Edition”