G'day all.

I am putting this question in here for lack (yet) of a VoIP forum.

I have a house LAN offering two RJ45 ports in most rooms of the house. (The LAN was installed and the cabinet wired up by a licensed tech.) These can be patched for either voice or data. There is a total of 18 patchable room ports.

Currently, I have two standard telephone lines connected - call them V1 & V2 for ease of reference. The two lines are wired through a patch panel so that there are 7 patchable lines for both V1 & V2. (All my handsets are self-powered so the REN numbers are very low.)

Recently, I bought a 2-line Cisco ATA with two assigned DID numbers. I plan to terminate one of the standard lines (V2) and replace it with one of the VoIP DID numbers. (V1 may get terminated in 6-12 months if VoIP lives up to expectations.)

This frees up 7 patchable lines for one of the VoIP DIDs. I am still short of a way to patch the second VoIP DID number to the room ports.

My question is: Can I use a 'dumb' switch to patch the second DID number?

Logically, these two lines in the ATA should have IP addresses and would therefore be switchable. But I would appreciate the thoughts of the pundits.

Thanks in advance. Yraen

Re: VoIP around my house

I understand everything about your posting except your question.

Your ATA is presumably in your patch rack, and is connected to your LAN on one side, and on the other side it has two phone sockets, each with their own VoIP numbers. And you have flexible wiring that allows you to patch from your patch panel to wall sockets in each room.

The thing I'd expect you to do for each of the two phone sockets on the ATA is grab a patch cable and patch from that socket to the socket on the patch rack that corresponds to the wall socket in the room where you want to put the phone. So one of the sockets in that room would be a data outlet and the other would be analog phone socket. And if you want to relocate the phone you move the patch cable.

So the bit I don't quite understand is what you mean by asking whether you can use a 'dumb' switch to patch the second DID number. Are you talking about one of those switch boxes of the sort they uses to use to switch a parallel printer between different PCs that's simply a multi-pole switch in a box, and rotating the switch to different positions connects the input to one of a number of different outputs? Yes you could use something like that. But why bother? If you've got to go to the patch rack to change the switch position it'd be just as easy and cheaper to not have the switch and just move the patch cable. Plus you'd have to find a 7-way 2/4-pole switch and make up a switch box like that.

By the way, you do know that LANs only use two pairs and [phones only use one or two, and that there's four pairs in your LAN wiring. Companies like Jaycar sell an RJ45 double adapter that lets you run both a phone and a LAN connection through a single cable by giving each of them two of the pairs.

**Unless you're using PoE (Power over Ethernet).

Re: VoIP around my house

After further thought ...

You don't need the switch. Read my previous post, in particular the bit about how ethernet only uses two pairs, and that you can get RJ45 double adapters that allow you to use the unused pairs to carry a phone connection as well as the LAN connection through a single 4-pair RJ45 cable.

You've got two analog phone ports on your ATA. And you've got two RJ45 ports in each room. So you make up to special multi-ended patch cable that connects the A port on the ATA to the unused pairs going to the A ports in EVERY room. And another one that does the same to connect the B port on the ATA to the unused pairs going to the B ports in EVERY room. Then with one of those RJ45 double adapter thingies on the end of its cable you can plug a phone into the A port in any room and it'll work and be the phone on the ATA's A port's VoIP number. Or if you plug it into the B port in any room and it'll work and be the phone on the ATA's B port's VoIP number. No switching required. No interference with the data connections to each port in each room.

If you want to move a phone to the other VoIP number you can just plug it into the other socket, even if the other phone is already connected to that number in another room. And if you want to move a phone to another room you just unplug it and plug it into the equivalent socket in the other room. You just have to figure out which pins to make the multi-ended patch cables wire to. But that's not hard to figure out. You'd have to figure that out to make a 'dumb' switch.

Re: VoIP around my house

Gordon, thank you for both of your replies.

I think I should clear up something ... By referring to a 'dumb' switch, I meant an unprogrammed 8-port ethernet switch of the kind sold by NetGear, NetComm, Dlink and others for around A$27 at Computer Fairs - probably more elsewhere.

I take your point about using 'unused' wires in the Cat 5e cable and I think I understand the concept you are advising.

However, doesn't this pre-suppose non-industry-standard wiring configurations for (a) the cable from ATA to patch-panel Krone plug (essentially turning it into a Y-connector so that it allows 2 x RJ11s into 1 x RJ45), and (b) from the voice room-port (also a Krone plug) to each individual telephone (so that the 2x2-pair setup goes to the correct handset)?

I also note in other forums (forae?) that mixing Cat 3 (standard flat 2-pair) telephone cable into a VoIP setup is expressly discouraged - Cat 3 inhibits bandwidth (vital for VoIP) and may also introduce line-noise.

Tanks again and cheers, Yraen.

Re: VoIP around my house

I'm not sure if I'm misunderstanding you or you're not clear that you are creating a network that's carrying two quite different types of signals. You have an ethernet network. And you are connecting analog phones to it. The ATA is an Analog Telephone Adapter. It plugs into ethernet and provides a connection for analog phones. The ethernet signal that goes into the ATA can be run through an ethernet switch, but the analog signal that comes out and goes to the phone most definitely can't. Not only won't it work, because an ethernet switch is designed to switch ethernet digital packets, but the ringer voltage could destroy the switch's electronics.

And similarly whilst the analog signal between the ATA and the phone can go through either Cat5 ethernet cable or the much lower quality/bandwidth phone cable, ethernet must not be cabled using phone-type cabling. Phone-type cabling is quite good enough to put an analog phone's signals through - like connecting between the ATA and the phone - but you don't put the ethernet signal that goes into a VoIP through it.

I think some of your/my/our confusion is that some business VoIP installations use ethernet phones. The phone has an ethernet socket on it and plugs directly into the ethernet network. They are in effect a combination all-in-one ATA and phone. They're good. But they're expensive. You wire them just like any other ethernet device on your LAN through with Cat5/5e/6 cable through a switch back to a router. But you're not doing that. You're trying to use a centrally-located ATA that outputs an analog signal then using your Cat5/5e/6 cabling to carry that analog signal out to remote wall sockets, and plugging an old-style analog phone in there.

Re: VoIP around my house

Thank you again Gordon - esp for the bang in the head.

Your last para is the key ... the analogue signal. I had totally ignored what the ATA was for.

I can use a centrally located ATA and connect it to 7 'phone' ports around the house, merely substituting one of the ATA DIDs for the present telco number and line. But I CANNOT connect the 2nd DID thru a digital/ethernet switch.

Thank you, sir, for the wake-up call Cheers, Yraen.