cat 3 cable

furby

Hi,

I read in a network+ book that the data throughput of a cat 3 cable is 10 mbps but another source said that cat 3 has a throughput of 100 mpbs.

Which is correct?

Thanks.

BubbaJ

Category 3 is up to 10 Mbps.
Category 4 (no longer recognized) is 20 Mbps (used for 16 Mbps Token Ring)
Category 5 (no longer recognized) is 100 Mbps
Category 5e is 1000 Mbps
Category 6 is 1000 Mbps and capability to 10,000 Mbps with distance limitations.
Category 6a (not yet recognized) will reduce crosstalk enough to allow 10,000 Mbps for the full 100 meters.

elathrop

100BaseT4 uses Cat 3 and allows a throughput of 100Mbs. It uses all 4 wire pairs in the Cat 3 wire. However, I don't see 100BaseT4 listed in the exam objectives so, I'm going with Cat 3 = 10Mbs.

BubbaJ

I found some official documentation, but it doesn't necessarily apply to the test:

ANSI/TIA/EIA-568-B categories of horizontal cables:

Categories 1 and 2 These balanced twisted-pair cables are not recognized in the ANSI/TIA/EIA-568-B standard. They are typically used for voice and low-speed data(9600 b/s or less) transmission rates.

Category 3 This designation applies to balanced twisted-pair cable and connection hardware that is recognized in the ANSI/TIA/EIA-568-B.1 standard for voice applications but is not recommended for new installations. The characteristics of these cables are specified up to 16 MHz. They are typically used for voice and data transmission rates up to 10 Mb/s (e.g., IEEE 802.5 4 Mb/s balanced twisted-pair annex and IEEE 802.3 10BASE-T).

Category 4 The characteristics of these balanced twisted-pair cabling components are specified up to 20 MHz. They were intended to be used for voice and data transmission rates up to and including 16 Mb/s (e.g., IEEE 802.5 16 Mb/s balanced twisted-pair standard). This category is no longer recognized in ANSI/TIA/EIA 568-B.1 and ISO/IEC 11801 Ed.2:2002 standards.

Category 5 The characteristics of these balanced twisted-pair cabling components are specified up to 100 MHz. They are intended to be used for voice and data transmission rates up to and including 100 Mb/s (100BASE-TX). This category is no longer recognized in ANSI/TIA/EIA 568-B.1 for new data cabling installations.

Category 5e The characteristics of category 5e cabling components are specified up to 100 MHz, with additional transmission parameters necessary to support applications that use all four pairs in the cable for simultaneous bidirectional transmission (such as IEEE 802.3 1000BASE-T).

Category 6 Category 6 channels have a bandwidth of 200 MHz ( PSACR > 0) and parameters that are specified up to 250 MHz. Category 6 cabling is intended to support more demanding applications, including broadband video, and more robust performance for gigabit applications (e.g., IEEE 802.3 1000BASE-T). It is well positioned to support future multigigabit applications that take advantage of the extended bandwidth and improved SNR.


Cabling Standards Document Summary

Several standards documents specify or recommend transmission parameters for the different cabling systems. Following is a summary of the most common documents:

• ANSI/TIA/EIA-568-B.1, Commercial Building Telecommunications Cabling Standard, Part 1: General Requirements, 2001—Specifies cabling requirements for categories 3 and 5e and optical fiber, cabling distances, telecommunications outlet/connector configurations, and a recommended topology.

• ANSI/TIA/EIA-568-B.2, Commercial Building Telecommunications Cabling Standard, Part 2: Balanced Twisted-Pair Cabling Components, 2001—Specifies categories 3 and 5e component requirements for cables, cords, and connecting hardware.

• ANSI/TIA/EIA-568-B.2-1, Commercial Building Telecommunications Cabling Standard, Part 2: Balanced Twisted-Pair Cabling Components, Addendum 1, Transmission Performance Specifications for 4-Pair 100 Ohm Category 6 Cabling, 2002—Specifies minimum category 6 transmission requirements for cables, cords, connecting hardware, permanent link, and channel.

• ANSI/TIA/EIA-568-B.3, Optical Fiber Cabling Components Standard, 2000—Specifies minimum requirements for optical fiber components used in premises cabling (e.g., cable, connectors, connecting hardware, patch cords, and field test equipment).

BubbaJ

elathrop wrote:

100BaseT4 uses Cat 3 and allows a throughput of 100Mbs. It uses all 4 wire pairs in the Cat 3 wire. However, I don't see 100BaseT4 listed in the exam objectives so, I'm going with Cat 3 = 10Mbs.

100Base-TX and 100Base-T4 were released at the same time in 1995 under the IEEE 802.3u standard. Category 5 cabling was generally cheaper than the higher cost of the 100Base-T4 components.

In 1997, 100Base-T2 (IEEE 802.3y) was introduced to allow 100 Mbps operation on 2 pairs of Category 3 cable. By that time, category 5 cable was entrenched and the standard never really went anywhere.

furby

Thanks for the replies.

I also read though that cat 5e runs on 350 mhz instead of 100 mhz

BubbaJ

furby wrote:

I also read though that cat 5e runs on 350 mhz instead of 100 mhz

No. Category 5 and Category 5e are the same, except that 5e has to pass some new tests like NEXT. Category 6 is only up to 250 MHz.

dgray2003

BubbaJ wrote:

furby wrote:

I also read though that cat 5e runs on 350 mhz instead of 100 mhz

No. Category 5 and Category 5e are the same, except that 5e has to pass some new tests like NEXT. Category 6 is only up to 250 MHz.

yes cat5e calbing does run at 350MHz check this site out
http://www.computercablestore.com/detail.aspx?ID=10

also some of the cat5e cabling is fused together as 8 smaller cables in 1 so you have to separate them before you build to specification

BubbaJ

oreoman685 wrote:

yes cat5e calbing does run at 350MHz check this site out
http://www.computercablestore.com/detail.aspx?ID=10

As you should note, it says it is Enhanced Cat 5e cable. This is not the standard. The standard for commercial cabling in the U.S. is set by ANSI/TIA/EIA-568-B.

The standards set a minimum to insure performance. It would be disingenuous to claim that Category 5e can do 350 MHz since a cable that can only do 100 MHz meets the Category 5e standard. Not all Category 5e cable can do 350 MHz, and that doesn't mean that it doesn't qualify to be verified as Category 5e cable.

In other words, all Category 5e cable can do 100 Mhz, but not all Category 5e cable can do 350 MHz.

furby

which standard is being used for the network+ exam?

BubbaJ

furby wrote:

which standard is being used for the network+ exam?

To be Verified as Category 5e it has to pass the 100 MHz test. The 350 MHz in the ad is a marketing ploy. Category 5e at 100 MHz is capable of running 1000Base-T so the extra 250 MHz of testing gains nothing.