Dear Forum Memeber,
I have a scenario to discussed, i have 4 Analog lines from local exchange and we have 20 IP phone need to Connect these ip phone with them for ip phone dial out and also recive the call from the analog lines , which Hardware i need to connect these analog lines with 20ip phone extensions
You need something like this configured with 4 FXO ports…
Which country are you in?
Before you go too far, note that most of the developed world is currently in the process of removing analogue lines, and, at least replacing them with VoIP (using SIP0 to the customer premises, an ATA, and analogue for the last few feet, and even, as the default consumer position, in the UK, with DECT digital to the handset.
Normally the VoIP that directly replaces the analogue line is locked down, so you can’t get the credentials to register with it directly, but you may be able to port the numbers out, to an unlocked down SIP account.
Actually, in most such countries, you cannot start a new analogue line contract. All new services will be VoIP to the premises.
You need to investigate the plans for your country. Otherwise, you may end up with the only analogue connection being a 1.5m jumper cable (and a very short trace within the phone itself).
Also note that Sangoma have an interest in selling PCI(e) cards, but many people would use analogue telephone adaptors, which connect to the main PBX over SIP and Ethernet, not direct to the motherboard. You will find many thread here relating to the use of ATAs.
This isn’t true.
Some countries are like this, correct. But I just had a new 50-pair pulled in from the street that goes back to the Central Office here in Portland OR, United States. Of course, this is to a business located in downtown PDX.
It’s important to keep in mind, of course, that unlike some countries, in the US, the telephone companies are not nationalized they are private, not government-run. (it’s quite possible to have a government technological Czar running a nationalized telephone company who’s running it based on feel-good articles he reads off In-Flight magazines and posts off the Asterisk community forum - lol - but that’s true of all government-run stuff. Ignorant people tend to infest governments)
Analog lines are not dead. Privately owned phone companies have large amounts of existing copper that was put into existing rights-of-way and depending on the condition of it and the number of analog POTS subscribers they have in a CO they may elect to maintain it or they may not. These are pragmatic business decisions. Obviously, if they have a water compromised 200 pair cable in the street they need to pull out, they will pull in a replacement along with a fiber cable - but the days of just wholesale replacing copper with fiber just because it’s copper are over.
In fact, in some locations the phone companies are completely out of fiber, and are running SFP’s that are bi-directional over a single strand of glass. I just had a discussion a few months back with someone who swore I was lying, that all fiber was in pairs, with a send and receive strand - until I posted links off Amazon to bi-di SFPs. In those locations if they have existing copper infrastructure, they will indeed use it for low volume POTS runs instead of running fiber to the subscriber.
It’s all based on density. Fiber requires maintenance just as copper does, and now that fiber infrastructure has been in place for a long enough time for the usual age-related random electronic failures in optical pickups and so on, the phone companies are discovering that no, you can’t just replace your copper infrastructure with fiber and fire all your service techs. If they have an area with a high density of copper POTS subscribers, and pretty static growth, it’s cheaper to maintain the copper than pull it all out and replace with fiber, and then force all the subscribers over to fiber. Particularly if the infrastructure is all overhead. Underground infrastructure tends to degrade faster.
You just cannot make broad brush based assumptions. And even if the phone company has replaced the back-end infrastructure, they may still do copper handoff to you via POTS.
We also see copper still in other interesting niche products. For example last week I just plugged in an Asterisk FreePBX system to a brand new overhead paging system with a Bogen amp, and controllers. The Bogen paging equipment accepted audio paging input from the phone system via POTS. In fact, it even had a switch on it to switch it’s POTS port from either FXS or FXO mode depending on the port card you were using. I used a Cisco 2620 router with a FXO port card in it that I blew the dust off of when I pulled it out of storage - note that this router model is 27 years old - and it is so old that it was in the era where Cisco was still new to SIP and the router IOS does not permit you to initiate a SIP call only receive one so you can’t use FXS cards in the router, even though Cisco manufactured them back in the day. (incidentally I derived immense satisfaction showing that setup to the installer who was convinced I had to buy a $2000 voip paging unit - the expression on his face was the glummest I’ve ever seen when he realized he wasn’t going to make bank on that)
I also second the recommendation for using analog TAs. For starters the secondary market is littered with gear, for example an ISR4321 with 4 FXO ports in it will run you around $60USD, here’s one:
Cisco ISR4321/K9 Router w/ NIM-4FXO – Factory Reset No Clock Bug w/Power Supply | eBay
If you know Cisco gear you can get one of these and your off to the races. The Sangoma equivalent is this:
Vega 60G - Sangoma Technologies
One huge advantage of TAs is they allow you to virtualize your PBX
I even hear that Grandstream TA’s have rotary pulse generators and detectors in them that can be enabled for those with the truly antique stuff - while I can’t imagine a telephone company left today that can’t do Touch Tone dialing, I’ve seen people put rotary dial telephones on VoIP systems for funsies…
Hi there
In the Netherlands the national telco was privatised decades ago. The are now several telcos providing FTTH.
My POTS number was ported to VOIP several years ago. The copper cables are still there, but they are no longer connected to anything. Except where FTTH is not yet available, in which case VOIP via ADSL is used.
The downside is that with a power failure the phone no longer works. The current telecommunication infrastructure has the odd battery here and there, but unlike the traditional POTS power supply, they stop functioning after a few hours. In which case you have to go to an area where cell towers still work. So if you are (temporary) disabled and need emergency services, no one is going to help you.
Telcos know this, but considerations like these don’t have a high priority.
Regards,
Rob
The UK telecom infrastructure was privatised over 40 years ago, but we are still well into the stop sell period for analogue lines.
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