Though fiber optic cabling is in full swing in recent years, it still can not take the place of the copper cabling completely. As one type of the copper cabling, Unshielded Twisted Pair (UTP) cable is most certainly by far the most popular cable around the world. Because UTP cables are used not only for networking but also for the in television, video, and telephone applications. When we talking UTP cables, we’ll likely come across Cat 5, Cat 5e, and Cat 6 cables with no clue as to what these designations mean. Why are they called as Cat with a number? Are these cables the tails of felines, and the number denotes how many of their nine lives remain? Of course, it is just a joke for the outsider. Cat here is short for “category”, and the number, such as 3, 5, 5e, 6 etc., refers to the generation of twisted pair Ethernet technology. Though it is said that the Cat 5 cable is the most popular of all UTP cables in use today, many new generation of UTP cables still come to the market. This cause us to think why we need different categories of cables?
Before explaning why we need different categories of cables, now let’s have a quick look at each of the UTP categories available today:
|Cable Type||Data Rate||Frequency||Applications|
|Cat 1||up to 1 Mbps||/||Traditional Telephone & ISDN (Integrated Services Digital Network)-Modem|
|Cat 2||up to 4 Mbps||/||Token Ring|
|Cat 3||up to 10 Mbps||16 MHz||Token Ring & 10BASE-T|
|Cat 4||up to 16 Mbps||20 MHz||Token Ring|
|Cat 5||up to 100 Mbps||100 MHz||Ethernet, Fast Ethernet and Token Ring|
|Cat 5e||up to 1000 Mbps||100 MHz||Gigabit Ethernet|
|Cat 6||up to 1000 Mbps||250 MHz||Gigabit Ethernet|
|Cat 7||up to 10 Gbps||600 MHz||Ultra Fast Ethernet|
|Cat 7a||up to 10 Gbps||1000 MHz||Ultra Fast Ethernet,CATV (862 MHz).|
|Cat 8||up to 40Gbps||2 GHz||40 Gigabit Ethernet|
From the above table, we can easily find that except Cat 1, the other categories of cables are designed for computer networking. For instance, Cat 2 is used mostly for token ring networks, supporting speeds up to 4 Mbps. For higher network speeds you must use Cat 4 or Cat 5 cable, but for 10 Mbps Cat 3 will suffice.
Actually, Cat 3, Cat 4 and Cat 5 cable are 4 pairs of twisted copper cables and Cat 5 has more twists per inch than Cat 3 therefore can run at higher speeds and greater lengths. The “twist” effect of each pair in the cables will cause any interference presented/picked up on one cable to be cancelled out by the cable’s partner which twists around the initial cable.
From Cat 5 cable, UTP cables began to be used in Ethernet application. And Cat 6 cable was originally designed to support gigabit Ethernet, although there are standards that will allow gigabit transmission over Cat 5 cable (here refers to Cat 5e). Though a Cat 5e cable infrastructure will safely accommodate the widely used 10 and 100 Mbps Ethernet protocols, 10BASE-T and 100BASE-T respectively, it may not satisfy the needs of the next Ethernet protocol, gigabit Ethernet (1000BASE-TX). Thus, Cat 6 Cable was developed to ensure 1000BASE-T performance as well as accommodate other protocols.
As for the 10 Gigabit Ethernet, Cat 7 cable came to the market. Cat 7 network cabling is used as a cabling infrastructure for 1000BASE-T (Gigabit Ethernet) and 10GBASE-T (10-Gigabit Ethernet) networks. Cat 7a is the enhanced version of Cat 7. It can perform up to frequencies of 1000 MHz and 40 Gbps.
Obviously, though fiber optic cable seems like the trend of future cabling, the development of copper cabling do not mean to stop. After seven generation of evolutions, Cat 8 cable was launched to the market in order to satisfy the 40G Ethernet (40GBASE-T). Cat 8 cable will contain four shielded twisted pairs and have a diameter about the same as Cat 6a and Cat 7a cables, but the bandwidth is specified to 2 GHz.
Is there possibly a Cat 9 in the future? Only time will prove everything.
If you have read this far, you may clearly know why we need so many categories of cables. Of course, this does not mean that you should buy all of these cables home or you should use copper cabling instead of fiber optic cabling. Different categories of cables are with different characteristics and used for different applications. And copper cabling sometimes seems to be better than fiber optic cabling in short distance. You should choose the right cable according to your application and working environment.
Fiberstore is a professional manufacturer and supplier for network solutions, including fiber optic subsystems, components and copper network components. You could find all kinds of UTP cables or fiber optic patch cables, as well as a comprehensive solution of transceiver modules for different Ethernet protocols, such as 1000BASE-T SFP, 1000BASE-SX SFP, etc. For more information, please contact us directly by sending E-mail to firstname.lastname@example.org.