Module3 - Networking Media

coaxial cable

At one time, _____ was the most widely used network cabling

coaxial cable

In its simplest form, _____ consists of a core of copper wire surrounded by insulation, a braided metal shielding, and an outer cover

shielding

The term _____ refers to the woven or stranded metal mesh that surrounds some types of cabling

noise

Shielding protects transmitted data by absorbing stray electronic signals, called ____, so that they do not get onto the cable and distort the data

dual shielded

Cable that contains one layer of foil insulation and one layer of braided metal shielding is referred to as _____

core, solid, stranded, copper

The ____ of a coaxial cable carries the electronic signals that make up the data. This wire core can be either ___ or ____. If the core is solid, it is usually _____.

insulating

Surrounding the core is a dielectric _____ layer that separates it from the wire mesh

braided wire mesh

The _____ acts as a ground and protects the core from electrical noise and crosstalk

Crosstalk

_____ is signal overflow from an adjacent wire

short

The conducting core and the wire mesh must always be kept separate from each other. If they touch, the cable will experience a ____, and noise or stray signals on the mesh will flow onto the copper wire

electrical short

An _____ occurs when any two conducting wires or a conducting wire and a ground come into contact with each other.

twisted-pair cabling

Coaxial cable is more resistant to interference and attenuation than ______

Attenuation

_____ is the loss of signal strength that begins to occur as the signal travels farther along a copper cable

coaxial cabling

For this reason, _____ is a good choice for longer distances and for reliably supporting higher data rates with less sophisticated equipment

Thinnet cable, NIC

______ is a flexible coaxial cable about 0.64 centimeters (0.25 inches) thick. Because this type of coaxial cable is flexible and easy to work with, it can be used in almost any type of network installation. ______ can connect directly to a _____

Thicknet cable

_____ is a relatively rigid coaxial cable about 1.27 centimeters (0.5 inches) in diameter

Standard Ethernet

Thicknet cable is sometimes referred to as ______ because it was the first type of cable used with the popular network architecture Ethernet

thicker

Thicknet cable's copper core is ____ than a thinnet cable core

BNC T connector

This connector joins the network interface card (NIC) in the computer to the network cable

The BNC barrel connector

This connector is used to join two lengths of thinnet cable to make one longer length

BNC terminator

A _____ closes each end of the bus cable to absorb stray signals

Twisted-pair cable

______ consists of two insulated strands of copper wire twisted around each other.

twisting

The ____ cancels out electrical noise from adjacent pairs and from other sources such as motors, relays, and transformers.

Unshielded Twisted Pair (UTP)

____ is now the most popular form of LAN cabling

UTP, 10BaseT

____, using the _____ specification, is the most popular type of twisted- pair cable and is fast becoming the most popular LAN cabling

voicegrade, datagrade

UTP Category 1: _____; Category 4: ______

Category 1

This refers to traditional UTP telephone cable that can carry voice but not data transmissions. Most telephone cable prior to 1983 was _____ cable

Category 2

This category certifies UTP cable for data transmissions up to 4 megabits per second (Mbps). It consists of four twisted pairs of copper wire

Category 3

This category certifies UTP cable for data transmissions up to 16 Mbps. It consists of four twisted pairs of copper wire with three twists per foot

Category 4

This category certifies UTP cable for data transmissions up to 20 Mbps. It consists of four twisted pairs of copper wire

Category 5

This category certifies UTP cable for data transmissions up to 100 Mbps. It consists of four twisted pairs of copper wire.

Category 6

This category is up to 1000 Mbps (200 MHz)

Shielding

_____ reduces crosstalk and limits external interference

Shielded Twisted Pair (STP)

Usually, wiring includes a wire braid inside cladding or sheath, and a foil wrap around each wire pair

Shielded Twisted Pair (STP)

Uses two pairs of 150 ohm wire (defined by the IBM cabling system), and was not designed to be used in Ethernet applications, but it can be adapted to

STP

____ cable uses a woven copper- braid jacket that is more protective and of a higher quality than the jacket used by UTP.

RJ-45

Twisted-pair cabling uses ____ telephone connectors to connect to a computer

eight, four

The RJ-45 connector houses ____cable connections, while the RJ-11 houses only ____

Distribution racks and rack shelves

______ can create more room for cables where there isn't much floor space. Using them is a good way to organize a network that has a lot of connections

Expandable patch panels

These come in various versions that support up to 96 ports and transmission speeds of up to 100 Mbps

patch cable

One of the skills required of a network technician is making a twisted-pair _____

Jack couplers

These single or double RJ-45 jacks snap into patch panels and wall plates and support data rates of up to 100 Mbp

Wall plates

These support two or more couplers

fiber-optic cable

In ______, optical fibers carry digital data signals in the form of modulated pulses of light

fiber-optic cable

This is a relatively safe way to send data because, unlike copper-based cables that carry data in the form of electronic signals, no electrical impulses are carried over the _____

Fiber-optic cable

_____ is good for very high-speed, high- capacity data transmission because of the purity of the signal and lack of signal attenuation

core, cladding

An optical fiber consists of an extremely thin cylinder of glass, called the ____, surrounded by a concentric layer of glass, known as the _____

Plastic

____ is easier to install, but cannot carry the light pulses for as long a distance as glass

Kevlar fibers

The _____ in the fiber-optic connector are placed between the two cables

Fiber-optic cable transmissions

______ are not subject to electrical interference and are extremely fast, currently transmitting about 100 Mbps with demonstrated rates of up to 1 gigabit per second (Gbps).

Single-mode

costs more and generally works with laser-based emitters, but spans the longest distances

Multimode

costs less and works with light emitting diodes (LEDs), but spans shorter distances

bandwidth

In computer networking, the term _____ to the measure of the capacity of a medium to transmit data

Baseband systems

_____ use digital signaling over a single channel

baseband transmission

With _______, the entire communication channel capacity is used to transmit a single data signal.

bandwidth

The term _____ refers to the data transfer capacity, or speed of transmission, of a digital communications system as measured in bits per second (bps)

Broadband systems

______, as shown in Figure use analog signaling and a range of frequencies.

analog transmission

With ______, the signals are continuous and non-discrete

568 Commercial Building Wiring Standard

The TIA/EIA developed the document “_______,” which specifies how network media should be installed to maximize performance and efficiency

Structured Cabling

Specifies how cabling should be organized

work area

The _____ is where computer workstations and other user devices are located

Horizontal wiring

_____ runs from the work area’s wall jack to the telecommunications closet and is usually terminated at a patch panel

equipment room

The _____ houses servers, routers, switches, and other major network equipment, and serves as a connection point for backbone cabling running between TCs

Backbone cabling, vertical cabling

______ (or ______) interconnects TCs and equipment rooms

entrance facility

An _____ is the location of the cabling and equipment that connects a corporate network to a third-party telecommunications provider

Wireless

_____ technologies continue to play an increasing role in all kinds of networks

hybrid networks

Microsoft calls networks that include both wired and wireless components _____

mobile networking

Enable users to roam with their machines within certain limits

Mobile computing

_____ typically involves a third party that supplies transmission and reception devices to link the mobile part of a network with the wired part

transceiver

a transmitter/receiver device, called a _____ or an access point, must be installed to translate between the wired and wireless networks

access point device

An _____ includes an antenna and a transmitter to send and receive wireless traffic, but also connects to the wired side of the network

Wireless LANs

_____ send/receive signals broadcast through the atmosphere

Higher-frequency technologies

______ often use tight-beam broadcasts and require a clear line of sight between sender and receiver

Infrared light beams

_____ send signals between pairs of devices

virtual docking

Infrared transmissions are being used increasingly for _____

Laser-based transmissions

Any solid object or person blocking a beam blocks data transmissions

Wireless Fidelity (Wi-Fi)

The 1997 802.11 standard is also referred to as ______

Ethernet, airwaves

802.11 wireless is an extension to ____ using _____ as the medium; most 802.11 networks incorporate wired ____ segments

802.16 Worldwide Interoperability for Microwave Access (WiMax)

One of the latest wireless standards, _______, comes in two flavors: 802.16-2004 (previously named 802.16a), or fixed WiMax, and 802.16e, or mobile WiMax

fixed WiMax

_____ is being used to deliver wireless Internet access to entire metropolitan areas rather than the limited-area hot spots available with 802.11

Mobile WiMax: 802.16e

Promises to bring broadband Internet roaming to the public

Structured cabling

______ facilitates troubleshooting, modifying, and expanding a network cable plant

802.11 family

_____ promises to make wireless networking commonplace in homes and corporate environments

802.16

_____ provides up to 70 Mbps of bandwidth over long distances (30 miles) and can be used to create MANs

Mobile computing

_____ involves using broadcast frequencies and communications carriers to transmit and receive signals with cellular or satellite communications techniques

“demarcation point”

It is also where a connection to a WAN is made and the point where corporate LAN equipment ends and a third-party provider’s equipment and cabling begins— also known as the ______