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Question: How do I activate all of my phone jacks using VoIP, like Comcast CDV, Vonage, Lingo, Other VoIP providers?

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Computer Help's picture

How to activate all of your phone jacks in your home/condo/apartment and issues with back feeding
This is a step by step tutorial to get you on the right track!

*NOTE* Make sure you read everything starting at the top. You must have a clear understanding of everything so you don't get stuck. There are hints on what to do if something happens in sections of this site that might not direct to your situation. Take your time and read the entire article before making any decisions or actions. Most of all, be responsible!

The situation:
Now I know this isn't really computer related but I worked as a senior Technician for Comcast and thought I would be able to share some ideas on what I have done while I was working with them for (2) years + on Residential High Speed Internet, Cable, and CDV Comcast Digital Voice phone service. I have also done some work with their older (ISU) phone service. This service has an actual box attached to the back of your home with flashing green lights when the units enclosure has been breached or opened up.

Now you may have just purchased a VoIP service to cut your cost down on your monthly bill with the Telephone company, or perhaps because of long distance or other various reasons like service availability, or you are just sick of normal land line prices for your area. You may have performed the installation yourself, or called a Service Technician to come into your home and perform the installation for you.

I know when I worked for Comcast, residents who lived in a apartment or condo units were unable to have all of their jacks activated after VoIP was installed. This is not necessarily because we are lazy and did not want too, but because we do not have access to your junction box that contains your phone lines. To my previous knowledge in older units, these lines were installed by the local Telephone Company. However, I have received reports that this is not necessarily true in all case's. I have been told that the lines have been put in by the Electricians of the building, and in some cases where the buildings were built before the 1980's, that they could have been put in by 'Bell' before the initial break up in 1982.

While doing my work in the field I have noticed that the telephone junction box's were always locked. I assumed that the only people who had access to the key was the local phone company or the local providers for land line service in their area. This may in fact even be true. However, I have received reports that the actual landlords or apartment owners are the ones who have this key. This may depend from state to state or from different geographical locations. You will want to consult with the land lord and your local land line provider in your area if you need access to this junction box.

Understanding what a NID box is, and why it's important in telephone jack activation or back feeding VoIP signal/dial tone.
Your NID/Junction box is usually small and blue/gray on the back of your home. A picture of a NID/Junction box is shown further below if you wish to take a look. This box or enclosure will usually be attached or fastened to the back or side of your home or the complex building/unit.In Michigan their usually a small blue/grayish color with a few wires inserted into the bottom and one main wire from the air or ground perhaps.
This main wire that I am talking about is the drop/wire from the local phone company in your area. If you look at the image below, you will see what a typical residential NIX box looks like in my area.

*NOTE* Take a look in the bottom left corner of the picture. You will see a wire coming up from out of the ground. This wire is known as a underground drop that was installed by the local phone company.

*NOTE* It has been reported by someone who works for a large local phone company that a NID Box should NEVER be left open for a extended period of time. The box should always remain secured and tightly screwed back into place if opened. Failure to do so can result in damage to your NID Box and who wants to have to worry about paying for a new one because yours is damaged due to a poor decision not to keep it shut?

Click Thumbnail for large view.

What are those wires inside?
If you click on the above thumbnail, you see series of wires that bundle up into insulation and head toward inside the home. These are your phone wires that head to the back of your phone jack's inside your home. Inside these main wires can be standard phone wiring or newer Cat-5/3 which I will explain further into the article.

There are (2) pairs of smaller wiring also know as 'Twisting Pairs' in standard phone wiring and (5) pairs in Cat-5. Each pair is able send and receive analog or digital voice. You will have a Positive and Negative or a Outgoing and Incoming per Twisting Pair. Red or Blue usually corresponds to the positive. You can actually mix blue and red together and get the same results. The same thing goes for Blue/White and Green, which would correspond to be the negative.

The reason some phone wiring in your home will be Blue and Blue/White and some might be Red/Green is because phone companies and electricians are now using a cable called Cat-3 or Cat-5. A poster earlier said that phone companies do not run these wires. This is not necessarily true because throughout the years additional jacks may be installed by your phone company.

Example: You ordered DSL back in 2003 and you had the Technician install two additional jacks for your DSL router.

While most of it would have been installed by a electrician/building contractor or the previous residents of the home.

Cat5 and Cat3
Cat 3 or Cat 5 contains 3 or 5 twisted pairs of wiring inside the cable insulation it's self. Cat-5 cable is also used for High Speed Internet connections as many of you already know. In standard phone cables, there will be only (2) twisted pairs. You will see Red/Green and Yellow/Black colored twisted pairs which is capable of being used for two phones lines/phone numbers. That would be (1) twist pair per phone line or phone number.

The newer stuff (Cat-5/3) costs the same as the old stuff, so now you will see more Cat-5/3 cabling used for residential and commercial phone systems now a days. If you have an unused Cat-5 Jack in your room, you can actually tie it into your phone system and use it as a phone instead. You would only use Blue/Blue-white to do this for one phone line. Technically, you can use any colors you want as long as they all match up with the color codes currently running in the home. Copper is copper after all right?

What else is to the NID box?
Well, there is more to it than just your home's phone wiring inside the NID box. The way your old phone company or land line phone service would get you signal is by one of two ways.

1.) An Ariel drop or wire from the telephone pole to your house and attaches inside this box. This drop usually runs though the air in your backyard or side of your home.

2.) Same thing with the exception the drop or cable runs from the pedestal underground and comes up into your NID box. *You can see an actual example in the lower left corner of the picture shown above.*

This signal is then pushed or inserted into the NID Box and then travels down to the pairs of wiring that run to each jack inside your home. If you would picture a spider web effect with each corner being a phone jack and a direct line inserted to the center of the web. It would feed and deliver signal to all of these jacks connected to this spider web. This is a general idea on how things work from the pole to the jack you plug your phone into inside your residence.

Removing the local phone companies dial tone and interference from your phone system
You can legally and safely remove the dialtone from the old phone company away from your phone system. To do this, open your NID box and unplug the little phone jack you see inside it. This cuts off signal from their drop to your phone jacks. Often, ignorant VoIP Tech's will forget to do this when trying to back feed your jacks with their VoIP service. Sometimes it's works and some time's it doesn't. The reason it does not sometimes, is because the other phone companies run 90 Volts of electricity running though their services to give it enough power to ring your phones when someone calls you. When this electricity gets mixed in with VoIP phone service it causes the VoIP modem to go ["what the hell is going on?"] and it will randomly lose sync and all kinds of crazy things may happen.

Just because you don't have a dial tone from your old phone company, doesn't mean that the plug in your NID box is to not be un-plugged!!!!
There is still 90 Volts going though this and will cause you and your Installing Technician a ton of troubles!

Alternative method of land line service dial tone removal
A user that claims to work for a local phone company has urged that removing the little telephone plug inside your NID box is not really a great idea. He has suggested that the proper way of doing this would be to follow these steps:

1.) Open the NID box and lose red and green screw of the line you want to disconnect.

*If you have multiple lines hooked up to more than (2) screws you may want to read this entire article before moving further with these instructions*

2.) Take all of the little wires that were previously tightened into the red screw and twist them together where the insulation is stripped. After all of the wires are twisted together only where the copper of these little wires are showing then place a peice of electrical tape around where the copper is showing. This will result in all the wires connected together and disconnected from the binding posts.

3.) Repeat the same instructions listed in [Step 2] for the green screw wires as well.

Below is a simple diagram of what a a set of Binding Posts look like inside a NID Box.

Okay, so now you should have a decent understanding what a NID Box is, does, what it looks like, and how it involves VoIP services with in residential home.

What a Installing Technician might do at your residence
This next section will talk about things with VoIP from the house to the outside and things the Technician might do that you don't understand.

First thing the Technician will do, is hook up or run a Coaxial cable line to a Arris, Motorola or other type of modem that various types of VoIP services use. Some of them won't use this method and will get you a signal from the Internet instead. Where the signal comes from and how it gets to the modem is not a big deal in regards to back feeding your home and all of your phone jacks. The Technician will run some software or call dispatch in some shape or form to have your new modem provisioned, and to port your new or existing phone number to the modem. Once everything has been synced up and ported you should now be able to plug a telephone into the back of the modem and start making phone calls at this point.

Back feeding all of your telephone jacks with VoIP dial tone [101]
Ok, now you are at a point where the Technician is not paid to do your back feeding or for other reasons.

1.) You have a alarm, or alarm that is not compatible with the service. (False excuse in most case's)
2.) We don't provide this type of work to the customers. (Could be telling the truth)
3.) All of your jacks need to be rewired for the new service. (More than likely, false excuse.)
4.) This cannot be done. (Look surprised, and ask are you sure about that?)
5.) You live in a Apartment or Condo complex where we cannot access your NID or Junction Box. (Can be true in some case's.)

Whatever the reason, most of the time you can still activate all of your phone jacks if you want to spend the time to get things done right. All I can do is explain how to do these things and how they are done. If you don't use your head, and your not willing to try new ideas, stop reading and go hire someone who cares and wants your money. If your in the metro Detroit area, contact me. (Waves and Smiles)

The instructions on how to back feed or activate all of your phone jacks with VoIP phone service
If you are left in a state where the modem can make phone calls directly out of the modem then you will want to try the most obvious and easiest route first. If you have a Home Alarm System that sends a signal to a outside/home base or police station if someone breaks into your home, read all of the steps but don't take any action until reading step 3 in it's entirety. If you have a alarm that just makes noise if someone breaks in, you can proceed with Step 1 as normal.

Step 1.
Go to the back of your home and find the NID box. You will need a Phillips or Flathead screw driver. If you live in a apartment you might have to ask the building owners or local land line phone company for the key to your junction/NID box. I don't suggest breaking into it, but I can't stop you. Your goal is to remove any electricity and dial tone from the land line service that was previously installed. It does not matter if this was 100 years ago or recently. This connection has to be broken to work 100% with VoIP with no problems. To do this, simply unplug the little phone jack that you see inside the NID box or cut the incoming drop only if you have no phone jack inside this box. If you see multiple phone jacks, unplug them all. The only time you wouldn't unplug them all, is if you are keeping a phone number from your land line provider for FAX or any other reason. In this case, you would have to perform a process of elimination. Unplug one by one and run in the house and see once you have lost dial tone. Once you have lost dial tone run back out side plug it back in and unplug the remaining ones. Now you will want to plug the little phone jack back in and consider using one of the more safer methods of removal I explained earlier in this article.

If you are in a apartment, search for the area for your junction in the basement or outside in a pedestal. You will only want to cut the little wires that connects to your binding posts. Removing any outside signal that could interrupt your modem once it's plugged into your phone jack's. You may have to use a toner to find your lines if they are not labeled. Do not cut the main drop feeding the entire pedestal. Otherwise, you will disconnect land line service to your entire building. Use common sense here and you should be Okay.

Step 2.
Now you have all old land line services removed from your phone jacks wires. Good, now go back inside and go to your modem. Plug in a standard phone cord into your modem where dial tone on VoIP is active and working. Plug the other side into the nearest phone jack. That's it you should now have a dial tone on all jacks tied to the phone jack you plugged the cord into!

Step 3. *Residents will alarms that dispatch help over the phone line only*
You want to do the same thing but you have a home alarm system that notifies the police or fire department if it goes off right? There is some more advanced work that needs to be done in order to successfully back feed your home with this type of alarm system installed in your home. You may be thinking, well I spent a lot of money on a cellular device in my attic and that if anything happens, that this cellular device will be used. That may be true, but these devices are only designed to be used as back up in case of complete dial tone failure and should never be used as a primary source of contacting authorities if anything bad were to happen inside your home!

Step 3 A *Residents will alarms that dispatch help over the phone line only*
First thing you will want to do is follow Step 1 like everyone else and disconnect outside interferences. After doing this, you might notice your alarm beeping. This means it has no dial tone and there is trouble with the system. Don't worry about this at the moment. However, it would be good a idea to call your alarm company ahead of time and let them know of what your doing and tell them that your alarm system will be down for a period of time to prevent any false reporting from your cellular device (If you have one).

Step 3 B *Residents will alarms that dispatch help over the phone line only*
Second thing you will need to do is run a phone line that will insert into the back of your modem to the alarm box which is usually located down in the basement or in a closet. The method of how you run this wire is completely up to you. You may drill a hole in your floor and run it though the beams or even perform a wall fish. The method of running the wire doesn't matter. Once you run the wire from point A (VoIP Modem) to point B (Alarm System), you will need to tie that wire or primary (twisted pair) into your alarm system correctly. Please look at the thumb nail listed below->

Click Thumbnail for large view.

Step 3 C *Residents will alarms that dispatch help over the phone line only*
You will not want to unscrew the red and green or red and black wires from this outlet/jack box inside your alarm. Note: Only remove the black wire if no green wire is screwed into the box. Now splice your new cable and cut off the remaining pairs as you wish.(The end of the new cable you ran) (The end of the cable that will be inserted into the alarm box for back feeding) You will now loosen the primary twisted pair screws inside the outlet box but keep the twisted pair that is on the screws intact and remaining attached to the outlet box. Your primary goal is to insert the red with the red and the green with the green. You will do the same thing if your using Cat-5. Blue will be with the red, and Blue/White with the green.

If you don't understand this process, call your alarm company and ask to speak to an advanced Technician. They should be happy to assist you in how your exact alarm should be configured with VoIP. Explain to them that you have everything setup and your requesting what actions you should take inside their outlet box inside the alarm system.

You should now have the following scenario:
Four screws have wires wrapped around them and tightened. 1 Screw will have two positive wire and another screw will have two negative wires. One set being a wire that runs outside to your NID, the other pair that is incorporated will be from your phone line you ran to your modem. The other two screws will have a single pair running to your alarms circuit board.

Once you finally tie in or merge your modems new line's primary twisted pair to match your NID box's main line into the outlet box, you should have something looks similar to the image below in the phone jack/outlet inside your alarm box in the basement/closet.

Non alarm VoIP users can continue their instructions here as well.
Residents who may have decided to run a dedicated line to their NID Box (Called Home Running a line) may follow the instructions below with the alarm users. This will explain how to put together your fitting inside your office where the VoIP modem is.

Strip and insert the red wire so a little bit of copper is showing on your primary twisted pair. Do the same for the green wire. If you are using Cat-5 cable insert blue where red used to be and Blue/White where green or black used to be. The old drop or old wire you removed from your alarm box can be taped up and hidden out of site as it remains inactive for this installation.

Assuming you are near your modem with your phone line in one hand, and a standard telephone fitting in the other, you will want to put a fitting on your new telephone cable you just ran to your modem. Only use the primary pair on your new cable which will be Blue/Blue-White or Red/Green. Now you are going to insert this pair into the center of the standard telephone fitting. There are (4) slots to put this pair into. You will insert it so the tip or bouncy prong of the fitting is facing down or towards the floor with copper prongs towards your face and use the middle 2 slots out of the (4) total with the positive in the left center slot, and negative on the right center slot. If the very left slot inside the fitting was slot 1, you would insert the little positive wire of your primary twisted pair which is Red or Blue in slot (2) and negative which is Green or BlueWhite into slot (3). This leaves slots 1 and 4 empty on the fitting. Make sure the wires are tightly jammed up into their correct slots and crimped down good. Then go ahead and insert your new fitting into your VoIP modem. You should be good to go!

Comments and concerns can be addressed in the comments section of this page. I am sure there are some things I have left out or forgot to mention because there can be so many issues when trying to do this, so feel free to post your comments, questions, pictures, ideas or whatever!

NOTE: Things and color codes of wiring can be different per residence. The best thing you can do is ask if you want to be sure. You can do this in the comments section below without registering. I check all of my questions and blogs posted on this site daily if not every other day.

Article last revised on: 07/22/2008

Notes from a Telco Guy

Unplugging the cord from the test jack (or leaving the test jack door open, or insulating the plug with a cap or tape and shoving it back in the hole) will isolate your inside wire from the ILEC (local phone company) wiring, but DON'T DO IT THAT WAY!

The proper way to isolate your wiring from the good-ol' phone company is to physically disconnect your wiring from the binding posts, making sure you either clip off the bare copper or tape it over, and retighten the binding posts.

When you move out (and the next person moves in), or you decide to go back to the local telco, the installer will have to reconnect the wiring, which he expects to do if the service order made it out to the field. If you've had the test plug hanging loose inside the NID, there's a good chance that the test jack itself has become the home to a family of spiders, or the plug contacts are corroded from being exposed, requiring the installer to have to replace the module, or entire NID if the module is integrated into the unit. Caps and tape mangle the little fingers inside the test jack, or at the very least coat them in black goo.

In the area I work, both Vonage and Comcast are quite active. At least once a day, I have to break out a brand new module or replace the entire NID because the Comcast technician put a little cap on the cord and jammed it in the test jack, destroying the module, or the Vonage customer or technician has opened the test jack door and left it open for six months, allowing it to corrode.

If you don't re-tighten the binding posts when you remove your wiring, you allow the screw/washers/nuts to corrode where the wiring had been, resulting in similar issues.

Anyone care to guess why the phone bill went up, instead of down, when competition arrived? Yep, this is one of the factors...

As for the rest of the article, under "What are those wires inside?", in the second paragraph, change the words "phone companies" to "electricians". We haven't been responsible for inside wiring since the breakup of Ma Bell in 1982. In today's world, the same electricians who install all the electrical wiring are also installing coax, Cat-5 networking, telephone, and even fiber.

About using an alarm system, personal monitoring device or any other modem-based communication equipment with VOIP: In most cases, you can probably use that equipment on a VOIP line, but you will need to set the maximum baud rate to less than 14.4K/second (so much for FAX machines, 14.4 is as slow as they go). The voice bandwidth of VOIP service is significantly less than Plain Old Telephone Service, limiting or eliminating parts of the frequency spectrum that modems communicate with. With an alarm system, your alarm company may have the technical expertise to set it down to 2400 baud (or they might not...), your personal monitoring device company probably can't (definitely can't if it's a ankle bracelet system and you're under house arrest), and if you intend to use it for FAX... don't bother, you'll use up hours of your life and have nothing to show for it.

1 GHz worth of bandwidth on a plain 30 year old 10,000 foot twisted pair versus 4 KHz compressed, packetized and tossed onto the (by definition) unreliable internet... any bets which one is better? :)

For some good reading on the subject, try the Wikipedia VOIP article: Myself, I got much joy from the third sentence in the last paragraph under IP telephony in Japan. Summed up in few words.

Last words, I'll shut up: Apartment wiring, and house wiring, is owned and maintained by the property owner, not the telco, and as such is fair game to any and all comers. If any of you technicians or customers out there need access to your wire in the locked interface box, all you have to do is ask. It's locked not to keep you out, but the malcontent neighbor or person intent on service theft. As a technician, we will expect you to perform your task in a workmanlike manner, and suggest that you have your supervisor contact our supervisor (yes, they have each others number, unless you don't have a local office) to have the individual apartment wires brought out to a separate location. The building owner may be charged for the upgrade to his wiring setup; we don't expect to eat, nor do we expect you to, the cost of giving open access to the apartment inside wiring. And yes, the Comcast techs and us can often be found in the same booth come lunch time... ;)


Hi im recently training for Comcast on CDV service, the phone system were we are colors are blue/blue white, red/black and green/yellow, the techs usually use orange/orange white to back feed for blue/blue white, my question to you is how do they backfeed to phone jacks were emta is to get dial tone for the wiring that techs use on blue/bluewhite, orange/orangewhite, and also for red/black, green/yellow please answer back need best details on how to do it, about to go in field by myself do not want any errors thank you..If you cannot understand statment i would like a verbal conversation or some type of photos for scenrio...

Mark Green

Computer Help's picture

Mark, All the colors

Mark, All the colors mentioned at exactly all the same thing and stuff, (mostly). You should know the following within your training:

RED/GREEN pairs of wiring are typically the colors used on phone wiring from the 80's and 90's. You'll typically see Black and Yellow with this pair as wiring for a second phone line as well which isn't used much in residential.

Mostly everyone now that I know is using Cat-5. I don't know if it's because it's cheaper, has more pairs of wiring, or what. But it's all the same stuff, copper. I used CAT-5 Mainly when I used to do this work as it was given to me to use.

These are used as primary line colors:

Second line colors:

When you are using your own wiring to tap into a NID or phone junction in the basement, forget what colors the wiring is in your hands. You need to be only paying attention to what colors are being used in the home. A lot of it comes down to practice and common sense.

As we know Orange and Orange-White are common secondary line colors. But what if you open a NID and see Red/Green and Orange/Orange-White pairs? You put your green machine/line tester on Red/Green and get no Dial Tone. You do the same on Orange/Orange-White and do get a dial tone. What does this tell you?

It would tell me, Red/Green pair is a dead line they no longer use. They have an installer put a new line in and Orange/Orange-White was used by that installer as the primary colors for whatever reason. I would then drop dialtone from the old provider on the Orange/Orange-White lines and back feed my own Blue/Blue-White lines into it.

You need to use Dial Tone as your friend. It will tell you if what you suspect the colors on the customers wiring really means or not. I've had some tricky ones before and without being able to tap in using my green machine and hear dial tone come out on the fly, I would been there for hours trying to figure it out the hard way.

Computer Help's picture


Thank you for the reply. I didn't expect to get so many reads on this topic. The need for revision and clean up of the article seems to be a very needed assignment. I will work on re-editing a few things and adding in more pictures and diagrams as well.

Other professionals or experts feel free to comment if you feel something should be added or changed.

You can also post a question in the forums under the VoIP category or by posting a comment here.

-CPU Help Administrator.