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extend demark for T1s 1

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pcrequest

MIS
Jul 12, 2007
71
US
Best way to extend a demark about 150 – 200 ft ? 6 T1s today (maybe another 6 in the future). Running past a huge HVAC system (can’t avoid). T1 cabinets are planned to stay at the demark, unless there is a reason to move them (I don’t know any better). Special crimping tool? If STP, grounding considerations?
 
To give you a good place to test the circuits during install and in the future we have always put a patch panel at each end and CAT5 between well labelled. This makes it easy to do loop backs etc and know exactly what circuit you are messing with. Just my 2 cents worth!
 
I see plenty of discussions of extending a demarc on tek-tips and other places. Seems like a ton of opinions.

I haven’t seen much that deal with discussing the wiring on each side of the T1 cabinets. The crossover wiring (jumper wire?) from the demarc punchdown seems like the same for regular phone lines that’s being used for T-1s. From the smart jack, it seems people are using various STP, UTP, variations of CAT3, CAT 5, CAT6. There is an ISTP (Individually Shielded Twisted pair) T1 wire explained here: It’s most important property seems to be that the send pair is shielded from receive pair.

I’m wondering which wire side of a T1 cabinet (the demark facing side or the smart jack to router side) is “fussier” and if I should be looking at moving the T1 cabinets to the new server room. From smart jacks to csu/dsu in routers, I’d only need to go 10 feet or so. T1 cabinet to demarc would be ~150 feet.
 
To isolate tx/rx using standard wire, we have extended everything in out data centers using cat5 with blu/org/grn/brw wired to the TX of ports 1-4 on a patch panel. then a 2nd cable with the same wired to the RX of ports 1-4 on the patch panel. This allows you to extend 4 circuits for every 2 cables you install and isolates TX and RX on all of the circuits. For a larger install, you may want 25 pair wired to 24 TX and a 2nd 25 pair wired to 24 RX to have a full patch panel extended for T1.

-CL
 
I always advise to use T-1 two pair sheilded cable with a Rj48X on both ends so you can use data patch cords at the demark box and at the switch ends.
Good Luck,

Has been in the cabling business for about twenty years and is now the Sr PM for a cabling company located in the Los Angeles area.
Also a General Class Amatuer Radio Operator.
 
I'm really curious on whether I should move the T1 cabinets to the server room (again, i don't know any better) or extend after the smart jack. I called some of the phone companies that bill us for the T1s and they weren't helpful.

I read in


p. 58 that one can extend after the smart jack 1000 to 1200 feet unsheilded! I don't know what to do with drain wires, and I've read improperly installing STP (can act as antenna) can be worse that properly install UTP. I'm probably going to do this with CAT5e or perhaps UTP CaT6.

Am I correct that pins 1&2 on one end must be reversed at the other end, and 4&5 are the same? Can I punch both ends as TIA 568B, then use a patch cable to accomplish the 1&2 reversal? Is there a standard patch color or changer device the industry recognizes?

Thanks for the comments.
 
I probably have around 60 or so that we have extended using the 2 pair shielded two pair without any problems. As for the drain wire, just cut it off on the ends. Just like the extra shielding when you strip it out to terminate it on a jack, plug, or patch panel.

The foil shield just helps from outside interference from power and light fixtures along your route.

I have two 24 port Cat 5E patch panels i use for one project using the two pair cables. (point to point T-1's used for video) These are laid down on the backs so i can use patch cables to the Cisco routers. Really made for a nice installation. But you will have to play around with the wiring scheme. Regular USOC panels with RJ-45's would probably be easier.

When is the last time you helped someone, just because you were able to?

For the best response to a question, read faq690-6594


 
CAT 5e and CAT 6 cable is NOT for DS1 circuits! Category cables are for ETHERNET use. ETHERNET transmission is NOT DS1 transmission. Just because uninformed people do it, doesn't make it the right way to do it. I have covered this subject in a previous post here: thread575-1278151: Extending the demarc for a PRI

Using the right parts and materials helps keep "Murphy" away and the customers happy, especially when the work is done correctly.

....JIM....
 
Strange .... CAT5 seems to work VERY well for us!
With the abundance of colors readily available for CAT 5 we can immediately tell at a glance what the cable is being used for too.
 
Although not designed for it. it works without any problems. I could have ordered the USOC RJ-45 inserts Cat nothing for this "one" project, but I used what I had. If anything, what i used is rated for a lot higher speeds than the Cat nothing or 3 i could have used. With 2 redundant fiber rings (from different providers)10 to 100 Gig and 7 milti-mounts full of T-1's to different places around the state (we are the hub for NW Louisiana) we get a lot of practice.

I would not recommend or practice something that doesn't work or has problems.

When is the last time you helped someone, just because you were able to?

For the best response to a question, read faq690-6594


 
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