Unshielded Twisted Pair (UTP) cable is most certainly by far the most popular cable around the world. UTP cable is used not only for networking but also for the traditional telephone (UTP-Cat 1). There are seven different types of UTP categories and, depending on what you want to achieve, you would need the appropriate type of cable. UTP-CAT5e is the most popular UTP cable which came to replace the old coaxial cable that was not able to keep up with the constant growing need for faster and more reliable networks.
Characteristics of UTP
The characteristics of UTP are very good and make it easy to work with, install, expand and troubleshoot and we are going to look at the different wiring schemes available for UTP, how to create a straight through UTP cable, rules for safe operation and a lot of other cool stuff !
So let's have a quick look at each of the UTP categories available today along with their specifications:
Figure 1. The Different UTP Categories and their specifications
Category 1/2/3/4/5/6/7 – a specification for the type of copper wire (most telephone and network wire is copper) and jacks. The number (1, 3, 5, etc) refers to the revision of the specification and in practical terms refers to the number of twists inside the wire (or the quality of connection in a jack).
CAT1 is typically used for telephone wire. This type of wire is not capable of supporting computer network traffic and is not twisted. CAT1is also used by telco companies providing ISDN and PSTN services. In such cases the wiring between the customer's site and the telco’s network is performed using CAT 1 type cable.
CAT2, CAT3, CAT4, CAT5/5e,CAT6 & CAT 7 are network wire specifications. This type of wire can support computer network and telephone traffic. CAT2 is used mostly for token ring networks, supporting speeds up to 4 Mbps. For higher network speeds (100 Mbps or higher) CAT5e must be used, but for the almost extinct 10 Mbps speed requirements, CAT3 will suffice.
CAT3, CAT4 and CAT5 cables are actually 4 pairs of twisted copper wires and CAT5 has more twists per inch than CAT3 therefore can run at higher speeds and greater lengths. The "twist" effect of each pair in the cables ensures any interference presented/picked up on one cable is cancelled out by the cable's partner which twists around the initial cable. CAT3 and CAT4 are both used for Token Ring networks -- where CAT 3 can provide support of a maximum 10Mbps, while CAT4 pushed the limit up to 16Mbps. Both categories have a limit of 100 meters.
The more popular CAT5 wire was later on replaced by the CAT5e specification which provides improved crosstalk specification, allowing it to support speeds of up to 1Gbps. CAT5e is the most widely used cabling specification world-wide and unlike the category cables that follow, is very forgiving when the cable termination and deployment guidelines are not met.
CAT6 wire was originally designed to support gigabit Ethernet, although there are standards that will allow gigabit transmission over CAT5e wire.. It is similar to CAT5e wire, but contains a physical separator between the four pairs to further reduce electromagnetic interference. CAT6 is able to support speeds of 1Gbps for lengths of up to 100 meters, and 10Gbps is also supported for lengths of up to 55 meters.
Today, most new cabling installations use CAT6 as a standard, however it is important to note that all cabling components (jacks, patch panels, patch cords etc) must be CAT6 certified and extra caution must be given to the proper termination of the cable ends.
In 2009, CAT6A was introduced as a higher specification cable, offering better immunization to crosstalk and electromagnetic interference.
Organizations performing installations using CAT6 cabling should request a thorough test report using a certified cable analyzer, to ensure the installation has been performed according to CAT6 guidelines & standards.
CAT7 is a newer copper cable specification designed to support speeds of 10Gbps at lengths of up to 100 meters. To achieve this, the cable features four individually shielded pairs plus an additional cable shield to protect the signals from crosstalk and electromagnetic interference (EMI).
Due to the extremely high data rates, all components used throughout the installation of a CAT7 cabling infrastructure must be CAT7 certified. This includes patch panels, patch cords, jacks and RJ-45 connectors. Failing to use CAT7 certified components will result in the overall performance degradation and failure of any CAT7 certification tests (e.g using a Cable Analyzer) since CAT7 performance standards are most likely not to be met. Today, CAT7 is usually used in DataCenters for backbone connections between servers, network switches and storage devices.
The next pages show you how UTP cable is wired and the different wiring schemes. It's well worth visiting and reading about.
Reader interested can also visit our Network Cabling section to select amongst a number of articles covering UTP, X-Over cables, Fiber Optic cables and much more.
Back to Network Cabling Section
1. Which three elements are required to successfully connect to the Internet? (Choose three.)
an IP address
file sharing enabled
a network connection
server services enabled
access to an Internet service provider
an address obtained directly from the RIR
2. What type of connection point is a point of presence (POP)?
between a client and a host
between two local networks
between a computer and a switch
between an ISP and a home-based LAN
3. What is the term for the group of high-speed data links that interconnect ISPs?
Internet LAN
ISP backbone
Internet gateways
Internet providers
Internet backbone
4. Which device can act as a router, switch, and wireless access point in one package?
hub
bridge
modem
repeater
ISR
5. What is a major characteristic of asymmetric Internet service?
Download speeds and upload speeds are equal.
Download speeds are slower than upload speeds.
Upload speeds and download speeds are different.
Upload speeds and download speeds are irrelevant.
6 Refer to the graphic. What type of cabling is shown?
STP
UTP
coax
fiber
7. What are two common causes of signal degradation when using UTP cabling? (Choose two.)
installing cables in conduit
having improper termination
losing light over long distances
installing low quality cable shielding
using low quality cables or connectors
8 . Refer to the graphic. What type of cabling is shown?
STP
UTP
coax
fiber
9. What are three commonly followed standards for constructing and installing cabling? (Choose three.)
pinouts
cable lengths
connector color
connector types
cost per meter (foot)
tensile strength of plastic insulator
10. Which two places are most appropriate to use UTP cabling? (Choose two.)
between buildings
in a home office network
where EMI is an issue
in a cable TV network
inside a school building
in a manufacturing environment with hundreds of electrical devices
11. Which definition describes the term Internet?
a group of PCs connected together on a LAN
a group of PCs connected together by an ISP
a network of networks that connects countries around the world
a worldwide collection of networks controlled by a single organization
12. What does the tracert command test?
NIC functionality
the ISP bandwidth
the network path to a destination
the destination application functionality
13. What term describes each router through which a packet travels when moving between source and destination networks?
NOC
ISP
hop
segment
14. What type of end-user connectivity requires that an ISP have a DSLAM device in their network?
analog technology
cable modem technology
digital subscriber line technology
wireless technology
15. What does adherence to cabling standards ensure?
data security
no loss of signal
no electromagnetic interference
reliable data communications
16 Refer to the graphic. What type of cable is shown?
crossover
eight coax channels
multimode fiber
single-mode fiber
straight-through
17. What connector is used to terminate Ethernet unshielded twisted pair (UTP) cabling?
ST
BNC
RJ-11
RJ-45
18. What are two advantages of cable management? (Choose two.)
requires no preplanning
aids in isolation of cabling problems
protects cables from physical damage
provides compliance with future standards
provides a short-term solution for cable installation
19. Which two characteristics describe copper patch panels? (Choose two.)
uses RJ-11 jacks
uses RJ-45 jacks
supports only data transmissions
allows quick rearrangements of network connections
forwards transmissions based on MAC addresses
20. What are three characteristics of business class ISP service? (Choose three.)
fast connections
extra web space
free Windows upgrade
cheapest cost available to all users
additional e-mail accounts
replacement hardware at no cost
21. Why would an ISP require a CMTS device on their network?
to connect end users using cable technology
to connect end users using analog technology
to connect end users using wireless technology
to connect end users using digital subscriber line technology