higher grade STP cables for longer distance then 100 meters?

furby

Hi,

We were reading in the book of comptia network+ certification study guide, third edition from mcgraw hill that it is possible that with a higher grade cable it is possible to have a longer cable length then 100 meters.
But i have just learned that the maximum distance for UTP/STP cable is 100 meters.
Does anybody know if thats correct because im reading other books also but some books dont say anything about longers distances then 100 meters for UTP/STP cables.

I dont want to fail on the exam because of one question thats not correct.
I know its not about one question but it would be a shame.

Michel and Chantal

sprkymrk

As far as I know, for the test just use the 100 meter rule for STP/UTP cables. See tech notes here:
http://www.techexams.net/technotes/networkplus/mediatopo.shtml

Webmaster

Higher quality cables have less degradation of the signal so can support higher distances, however, as sprkymrk mentioned, for the test just use the 100 meter rule for STP/UTP cables. That's the standard and that's the level of 'basic' knowledge you should know for this exam.

furby

Thanks for the reply.

I will use the 100 meters for the exam.

Some books arent clear about the cable types.

Im reading three different books.

Im also trying to find information on the website of the TIA/EIA and the IEEE.

ph4nt0m

Lookout Furby, you can get pretty confused when the exam comes. I would advice you to stick with the material for now. I used 3 sources of books for the exam, and EACH ONE had a different cable lenght for fiber... luckly i didn't got any questions related to this. But for STP they always stated 100m except for the exam cram, got to love that book. : /

BubbaJ

I don't believe that STP or ScTP are currently recognized in the US. Only UTP is recognized for copper.

Ethernet does have an upper limit on length (about 140 meters) regardless of the cable quality. Longer distances won't allow a frame to fully fill the cable. Token Ring has a longer limitation.

TIA/EIA standardized on 100 meters: 90 meters of solid conductor horizontal cable, and 5 meter on each end of stranded patch cable. In the US, the stranded cable is allowed to be 20% worse than the solid conductor, while in Europe it is 50%.

Under certain circumstances, you are allowed to increase the patch cord length. You have to decrease the horizontal cable length proportionally (length of excess stranded + 20%), taking into account that the stranded cable doesn't perform as well as the solid conductor cable.

sprkymrk

BubbaJ wrote:

I don't believe that STP or ScTP are currently recognized in the US. Only UTP is recognized for copper.

Where did you hear that? I have used STP here in the states. It's used a lot in security/fire alarm systems as well. What do you mean "recognized"?
Thanks!

BubbaJ

The bible for this is ANSI/TIA/EIA-568-B. Currently, Category 3, 5e, and 6 are the only copper cables recognized for use in data communications in the U.S. I don't believe any shielded or screened versions are recognized. I don't have the standard with me, but I did find a reference that says CENELEC (Europe) no longer recognizes STP-A.

This is from The Telecommunications Distribution Design Methods Manual:

The categories used within the United States to rate products are:
• Listed.
• Classified.
• Recognized.
• Verified.

Listed
A product is Listed after it successfully completes a series of mechanical, electrical, and thermal characteristics tests that simulate all reasonable, foreseeable hazards. The Listed classification is exclusive to the product for the specific applications for which it was tested and is not valid for other applications.

Classified
A product is Classified after it is evaluated and passes tests for one or more of the following:
• Specific hazards only
• Performance under specified conditions
• Regulatory codes
• Other standards, including international standards
The Classified rating is generally restricted to industrial or commercial products.

Recognized
A product is Recognized after it is tested for use as a component in a Listed package and passes. These component products are tested for electrical, mechanical, and thermal characteristics. The Recognized classification is a more general-purpose approval than Listed because it
allows a product to be certified for a category of equipment uses. An example is insulated wire, which is Recognized as appliance wiring material, a category of uses that includes:
• Data communications.
• Telecommunications.
• Instrumentation.

Verified
UL also produces a performance verification of communications cabling with the classification of Verified. Cabling manufacturers and their cabling types are listed in the UL publication, Performance Levels Certification Program, for meeting the base performance criteria for the product, such as category 3, 5e, and 6. The Performance Verification Mark allows manufacturers to demonstrate that telecommunications cabling products are certified for both safety and performance, and comply with industry
performance standards and draft standards. The UL Performance Verification Mark also signifies the testing of copper and optical fiber
cabling products to industry performance standards such as ANSI/TIA/EIA, ISO/IEC 11801 Ed.2:2002, NEMA, and Telcordia. It can also be applied to UL Listed optical fiber cable Verified to Telcordia specifications. The
Verification Mark may also be applied to data transmission or optical fiber cable Verified to performance specifications only.

BubbaJ

sprkymrk wrote:

I have used STP here in the states. It's used a lot in security/fire alarm systems as well.

A real problem with STP or ScTP is cost. Proper installation calls for special (read expensive) termination hardware and more labor intensive (again, read expensive) installation techniques. Without both of those, the shield continuity is not guaranteed which spoils the whole purpose.

sprkymrk

BubbaJ wrote:

sprkymrk wrote:

I have used STP here in the states. It's used a lot in security/fire alarm systems as well.

A real problem with STP or ScTP is cost. Proper installation calls for special (read expensive) termination hardware and more labor intensive (again, read expensive) installation techniques. Without both of those, the shield continuity is not guaranteed which spoils the whole purpose.

This is very true, but especially in the alarm industry many must think it's worth it. Thanks for the clarification.

BubbaJ

You're welcome.

I used to be responsible for overseeing cable vendors that we hired so I earned the Registered Communications Distribution Designer (RCDD) certification. I was a cable vendor's worst nightmare: a knowledgeable customer with the certs to back it up. I had to fire a couple of companies becasue they tried to b.s. me about some stuff.

sprkymrk

You did appear to me to be a SME (Subject Matter Expert). Glad I didn't hammer away like a know it all when I asked what you were talking about, that would have benn embarrassing.