What's the best way to connect our IDF for our phones to our MDF. Right now all phone cabling in IDF is terminated to CAT5E patch panels. Distance from IDF to MDF is approx 375-400 ft. What's the max distance for 25 pair cat5e?

Thanks!

For voice you should be good. Any good phone system will push extensions atleast 2000 to 3000 feet.

But for data the cut off is 300 feet. After that you need to go fiber.

Ok the phone system is going to be an avaya ip office with digital extensions.

So just get some 25 pair patch panels and 25 pair cable and run back to MDF?

yep.

but it wont push ANY ip phones so keep that in mind

As I am not an avaya ip office expert, digital and slp sets need one pair and have no restriction other than that of the KSU. The aforementioned 2/3000 feet. Some less.

Most computer based telephones have the same restriction as a computer, the aforementioned 300 feet. So, if you can have a computer, you can have an IP set. An IP set is just a computer with the same restrictions as any other computer.

As far as the 25 pr CAT5e usable distance --- again if it is to use data, 300 feet M/L, for slp or digital, the above mentioned distances.

At the distances you mentioned, with no IP sets or computers, you should be okay for the voice sets.

These are generalizations but work on a rule of thumb.

KLD

Wrichey, you type faster than I do.

Thanks! good info to know. What would I do without these forums. Now to figure out what is the cleaneast way to run it back to the MDF considering everything is on CAT5E patch panels. We have approx 60 drops.

If you have traditional TDM phones . Which it sounds like you do they most likely will not be terminated 564b/564a anyway so Cat3 is all you need IMHO. Also please fill out your profile . We like to know who we are helping ! Thanks

if used for phone you will be fine.for data 295ft is the cut-off.You have to figure in for the patch cords.total length on data is 315ft.

Jamey

He is right about taking into consideration patch cords and the like. But the max is 328 for cat 5e and 90 meters for horizontal fiber.

back bones are much longer however they can range between 300m and 1000m depending on the cabling used.

wrichey is correct.

DING! DING! DING! DING!

You win a million dollar bar tab!

Not!

Good job anyway for knowing the answer.

I had a Nuvox person ask what a wiring specification was.

I died today....right then,

And here I got all excited about a bar tab. :toast:

There is another horizontal fiber cabling method called "centralized fiber." If using FTTD you can run all FOC back to a centralized location. This will exceed 90m, but fiber doesn't have the attenuation problems that copper does.
This will also improve switch port utilization rates, lower allocated floor space for TRs, lower utility rooms (1 room to cool, power, secure, etc.) and minimize fault-points.

Naturally, it will depend upon your buidling as to whether or not this is a feasible option. In very large buildings (spanning over many floors) the amount of cabling running to 1 room would simply be too much.

In this case a hierarchical star topology for the backbone would be in order, with horizontal fiber feeding the desks.