Replace RJ11 data cable for broadband internet using standard telephone cable?

The green data cable provided by att is a 2 pair phone type cable. Any phone type cable may or may not work.  A cat5 cable with an rj45 connector plugs into the yellow ports on the gateway. 

These cables should work as a replacement for the green data cable. 

http://www.cablesondemand.com/category/MPUSCat5E/product/MP-52RJ11UNNE/URvars/Items/Library/InfoManage/MP-52RJ11UNNE.htm

Can also be found on Amazon or monoprice. 

The standard flat phone cable isn't twisted pair cabling and thus doesn't protect from Radio Frequency interference, which is pretty important when sending the frequencies used for VDSL2 through the cable.  It might work for a very short cable, or in a very low RF noise environment, but I'd not want to try it myself.

in the nvg589 what broadband cable do I need exactly and coudl I get a link to the cable to buy it since the green one I had ripped and I need a new one I was going around stores and they didn’t have one they said it looked like a phone conector 

https://cablesondemand.com/cat5e-2-pair-rj11-data-cable-at-t-u-verse-verizon-fios-data-cable-cat5e-pbx-patch-cable-with-6p6c-rj11-connectors-straight-thru-mp-52rj11unne

Scroll down for different lengths. 

We are trying to move our router to a more central location in our home so the wifi signal is better for everyone. However, we are finding conflicting info on the interwebs, as per.. So our cat 5e cable coming from the modem into the router has only 4 pins, similar to a telephone cable, however everything online seems to only refer to the 6 pin connectors. The router has a smaller port & a RJ11 connector is too wide to fit, even if we only used 4 wires. What exactly do I need as far as the connector - can I grab some phone line connectors and use those on a cat 5e cable? 

RJ11 and RJ14 are the same size, they are both 6 position.  The only difference is that RJ11 is two connections (6P2C) and RJ14 is four connections (6P4C).  The connectors on the back of the Gateway are RJ14 (as there are four connections available, 6P4C).  An RJ14 plug would work, so if you have RJ14 plugs (with the 4 wires) then you can certainly use those and that will be fine.

If you only have RJ11 plugs (which are the same size, but only connect the middle pair), then you'd have to consider if you're single or dual pair.  If single pair, then you could use the RJ11 plus.  If you're dual pair, then you need to acquire and use RJ14 plugs.  Using RJ14 would be preferred even if you're currently single pair, just in case you get upgraded to dual pair in the future.

Thanks for the info, but the dilemna is that the actual port on the back of the router that connects to the modem is a smaller RJ port than these other connectors you are mentioning, at least from what I'm seeing when I look them up online. (or my search is pointing me in the wrong direction, lol!) The router input port is the exact same size as a typical telephone jack, but obviously I can't use a standard telephone cable, but can I use the connector that are used for phone cables or is there a different type of connector I need to search for? It shoud be something like 4P4C but I don't know what the RJ number would be for that. Thanks again!

The green DSL port is a 6P4C connector, also known as RJ14.  The Red and Yellow Ethernet jacks are 8P8C connectors, often called RJ45 (though slightly erroneously).