L1 Physical Communication Infrastructure (180-50-1)

Fiber Optic Cable construction

Core Cladding Coating

How many wire pairs can be terminated on a 66 block?

25 or 50

Fiber optic cable length ?

2km

Components fo a optical transmitter:

Encoder light source Connector

AT&T

American Telephone and Telegraph

ICANN

Internet Corporation for Assigned Names and Numbers

What ICANN functions coordinates the assignment ?

Internet domain names IP address numbers Protocol parameter and port numbers

how data networking professionals refer to topologies?

Logical and Physical topologies.

Advantages of Cloud Networks

Lower cost. Simplified network managment. Greater flexibility.

Signaling predominant in Ethernet networks

Baseband signaling

what services provides W3C?

Repository of Web information for developers and users Reference code implementations to embody and promote standards Various prototype and sample applications to demonstrate use of new technology

10Base2 (Thinnet)

Type RG-58 A/U, RG-58 C/U Maximum Distance 185 m(607ft)

ARIN

American Registry for Internet Numbers

Coaxial Cabling Characteristics

Bandwidth Noise Immunity Physical Installation Security

Client/server architecture primary advantages

Distributed applications Resource sharing.

Attenuation

Electrical characteristics of the cable, especially resistance. Insertion losses that occur where the cable is interconnected, terminated, or broken.

Transmission Problems and Characteristics

Electrical noise Crosstalk Attenuation Capacitance DC resistance Impedance Continuity and polarity Cable length

Which of the following cable types can transmit data farthest?

Fiber optic

Input/Output (I/O)

Input refers to data that enters a computer from the outside, Output is data a computer sends to the outside world

How the bits are transmitting on a fiber optic network?

a NIC converts outgoing bits to flashes of light that represents data bits. then the NIC receives and converts those signals into electrical bit patterns a computer can use.

How the bits are transmitting on a wireless network?

a NIC transmits bits by changing the pattern of radio wave that represents data bits. then the NIC receives and converts those signals into electrical bit patterns a computer can use.

What does TIA/EIA-568-C provied

provides users and vendors precise guidelines for premises wiring.

Crosstalk

specific type of noise, caused by an electrical signal in one cable that induces a voltage fluctuation in an adjacent cable.

A serial bus i/0

stream data 1 bit at a time

what standardized cable and equipment installation practice ensures?

that the network works as designed and supports changing technologies.

Types of Fiber Optic Cable

Multimode fiber is wide enough to carry more than one light signal. (Each signal is called a "mode.") Single-mode fiber is thin and can carry only one light signal.

Which of the following is most typical of a broadband network?

Multiple analog channels

What is a fiber optic cable?

a thin strand of glass or plastic, coated with a protective plastic jacket.

What makes a crossover cable different from a patch cord?

A crossover cable uses the 568A pattern on one jack, and the 568B pattern on the other. A patch cord uses the same pinout pattern on both jacks.

MAC address

Media Access Control. Unique address embedded in to the Network Card.

NEBS

Network Equipment Building Standards

NIC

Network Interface Card

There are two types of cross-connect devices:

Punch-down blocks Patch panels

Logical topologies

Logical topologies show where signals go.

what is Analog?

A signal is carried as a pattern of continually changing waves.

characteristic of Simplex communication

A signal may flow in only one direction. A commercial radio station uses simplex communication,

device driver (driver)

A small program used to communicate with a peripheral device, such as a monitor, printer, portable storage device, or keyboard.

Core

A solid fiber of highly refractive clear glass or plastic that serves as the central conduit for light. The diameter and consistency of the core varies depending upon the specification of the fiber.

clock speed

The clock spped indicats how many instructions per second the processor can execute.

What is the most common type of copper cable used in networks?

Twisted pair.

electrical noise

activity near copper LAN cable can distort the LAN signal, causing noise and errors. This is due to the physical principle that a fluctuating voltage on a conductor

A network OS (NOS)

also called a client/server OS, provides centralized control of all network resources. A network administrator can decide what each user may see and do on the network. By far, the most common NOS packages are Microsoft and UNIX/Linux servers.

General speaking what does amplitude describes?

amplitude describes the power of a signal.

Application Software

are software programs used to perform work.

How crosstalk is typically described?

as Near End Crosstalk (NEXT) and measure in decibels

Modulation

by first establishing a constant, consistent waveform called a carrier wave. We then use the signal pattern to change the carrier wave's amplitude, frequency, or both. Another device, such as a radio receiver, can then extract the signal by detecting the way the carrier wave has been changed.

How NEXT is measured?

by injecting a known signal on one line and measuring the strength of the induced signal on the adjacent line.

How Cancellation is produce?

by twisting two conductors around each other in a pattern that causes the radiated magnetic fields on each wire to largely cancel each other out.

how Shielding is provided?

by wrapping the main conductor with grounded conductive shield. It both protects the inner conductor from EMI/RFI, and also helps keep the cable from becoming an antenna (thereby producing EMI/RFI in other cables or equipment).

twisted pair cable

cable consists of two or more pairs of thin, stranded, insulated copper wires. The two wires of each pair are twisted around each other to cancel EMI and RFI. Each pair functions as a single conductor.

Broadband link

can transmit multiple signals (each on a different frequency)

master slave communication process

occurs when one node has much greater computing capacity that another.

Baseband

only transmit a single signal at any particular moment

tap

the poinr where a device connects to the bus.

Timing Synchronization

To accurately interpret a bit stream, the timing circuitry of the receiving NIC must be synchronized with the signal pulses. Line encoding schemes provide a way for this to occur.

The primary purpose of a device driver is to control hardware under the supervision of the OS. True or False?

True

types of copper cable used in LANs

Twisted pair cable is the most widely used media. Coaxial cable is found in older data networks, radio installations, and audio/video systems.

Signal categories according to basic characteristics.

Analog or digital One-way (simplex) or Two-way (half-duplex or full-duplex) Timed (synchronous) or not timed (asynchronous)

what is signal?

Any change in a measurable condition that is used to represent information.

The TIA/EIA-568-C structured wiring system

Building entrance Equipment room Vertical (backbone) cabling Wiring closets Horizontal wiring Work area

Which of the following network topologies connects devices to a shared straight-line cable?

Bus topology

What does a NIC do?

Connects a computer to a network. by generate and receive the signals that represent binary 1s and 0s.

Continuity

Continuity means that all necessary connections have been made, so that a continuous electrical circuit exists.

A UTP-based LAN can use two types of movable cables:

Crossover cables connect two NICs directly to each other. Patch cables (also called patch cords or straight-through cables) connect a device to a permanently installed cable, or to a hub or switch.

what are the ITU sectors

ITU-R—Radiocommunication Sector ITU-D—Telecommunication Development Sector ITU-T or ITU-TSS—Telecommunication Standardization Sector

Impedance

Impedance is the total opposition (including resistance and capacitance) of the flow of electrical current.

The TIA/EIA wiring standards assign each pair a number, as follows:

Pair 1: Blue and white-blue Pair 2: Orange and white-orange Pair 3: Green and white-green Pair 4: Brown and white-brown

Quad Wire cable pairs

Pair 1: Green (tip) and red (ring) Pair 2: Black (tip) and yellow (ring)

TIA/EIA

Telecommunications Industry Association/Electronic Industries Alliance

What is the main advantage of using balanced signaling on a serial cable?

The cable can be longer because balanced signaling is less vulnerable to interference.

Communication Synchronous:

The communicating parties or endpoints use time to organize communication. In a data network, two communicating computers use each clock "tick" to detect whether a digital bit is a 1 or 0.

Which of the following cable types uses a T-connector to connect each NIC to the cable?

Thinnet

Which of the following would not be used in a typical star topology?

Thinnet

Basic Input/Output System (BIOS).

This program contains the most basic instructions in the computer and is permanently written to an area of read-only memory (ROM).

10Base5 (Thicknet)

Type RG-8,RG-11 Maximum Distance 500m (1,640ft)

"demarcation point" or "demarc,"

Within the building entrance, the telecommunication company's cables are terminated on a device that makes it simple to connect the customer's equipment to the transmission line.

W3C

World Wide Web Consortium

How the bits are transmitting on a copper-wired network?

a NIC varies the voltage level on the line in a precise pattern that represents data bits. then the NIC receives and converts those signals into electrical bit patterns a computer can use.

Global Area Networks (GAN)

are designed to allow users to have unlimited uninterrupted network access anywhere around the globe via LAN, wireless, cellular,and satellite connections.

Metropolitan Area Networks.

are formed by connecting LANs in several locations across a city or small region. The links between LANs are typically leased from companies that provide telephony and data services.

Crossover Cables

directly connects two computers. These are useful for small home networks or for temporary connections between two computers.

Types of signal use on data networks to transmit signals.

electromagnetic energy—electricity, light, and radio waves

Wide Area Network (WAN)

essentially the same as MANs, but span longer distances. A WAN may include sites in the same country or multiple countries.

what does the width of a parrallel bus determines?

how much data can be transmitted at one time.

IEEE

world-wide society of technical professionals. In addition to promoting the development of electrical and electronic theory and methods,

what TDR measure?

measures the time it takes for a signal to travel down a cable and be reflected back.

Building Entrance

point of entry and exit for all telecommunication lines, including telephone, data backbones to other premises, and other wide area network (WAN) transmission facilities.

Full Mesh Topology

point-to-point links directly connects every site to every other site in the network.

electromagnetic interference (EMI),radio frequency interference(RFI) or EMI/RFI

property of one device or signal interfering with another

The term "memory" generally refers to?

random access memory (RAM)

Data Bus

transfers actual data,

address bus

transfers information about where the data should go.

A parallel bus

transmits many bits simultaneously, using multiple transmission channels or wires.

How are bits represented on fiber optic cable?

Pulses (on/off) of light

what is the standard for using UTP cable to implement 10-Mbps baseband Ethernet using a star topology?

10Base T

what are the two major ways to limit noise and crosstalk in a cable design?

Shielding Cancellation

UL

Underwriters Laboratories

How impedance is measured?

in ohms

Hosts

"host" refers to a computer that provides files, applications, or other resources.

Partial Mesh Topology

.A partial mesh provides less redundancy and reliability than a full mesh topology. However, it is much less expensive to implement because it requires fewer point-to-point links.

Hubrid Topologies

A network that mixes two or more topologies

How the clock speed is messured?

In cycles per second (Hz)

Which of the following is managed by the OS?

Keyboard input Screen display File I/O Peripheral control

Which of the following network topologies forms a closed loop?

Ring topology

Wiring Closets

The equipment in the wiring closet is known as intermediate distribution frame (IDF) equipment.

Coating

A reinforced plastic outer jacket that protects the cable from damage.

most common ty of Fiber optic cable LAN

62.5/125 micro millimeter

best IEEE standards?

802 series that defines the operation of LANs.

Cladding

A layer of clear glass or plastic with a lower index of refraction. When light traveling down the core reaches the boundary between the core and cladding, the change in refractive index causes the light to refract or bend back into the core. The cladding of each fiber completely contains light signals within each core. This effect is called "total internal reflection."

Which connector type is used with Thinnet coaxial cable?

BNC

What is the key reason that smart LAN administrators demand well-made cable connections?

Bad cable connections degrade a network's performance.

Communication Asynchronous:

Bits are not transmitted on any strict timetable. For example, a computer modem typically uses 8 bits to represent one character or letter.

UTP Categories

Cat 1: voice only Cat 2: 1 Mbps Cat 3: 10 Mbps Cat 4: 16 Mbps Cat 5: 100 Mbps Cat 5E: 100MHz 1Gbps Cat 6: 250 Mhz 10 Gbps Cat 7: 600MHz 10Gbps

CPU

Central Processing Unit

Two basic characteristcs that differentiate micropreocessors:

Data bus size Clock speed

Protocols

Data networks use many different types of rules for signaling.

Peer-to-peer networking software

Each individual user configures software settings to allow or disallow the sharing of that computer's resources by other users. There is no central authority that decides what users may have access to what resources.

What is the main advantage of star topology?

Ease of management

Types of energy used to transmit in data networks?

Electrical current over copper wire Light pulses over plastic or glass fiber Radio waves through free space

what does I/O stand for?

Input/Output

A sound card is what general type of computer component?

Input/output

ISO

International Standards Organization

IANA

Internet Assigned Numbers Authority

important funtions of multistation access unit (MAU)

It automatically detects when a node is not responding and bypasses it so that the ring can continue to operate It provides a "bridge" to other rings, sending information that is addressed to nodes on other rings across circuits to those rings, and accepting messages from other rings for its nodes

Which of the following are the two primary types of light sources in fiber optic cables?

Laser diode and LED

10BaseT Wiring Rules

Maximum data rate 10Mbps Maximum Hubs or repeaters 4 Maximum hubs connected to one central hub 12 Maximum segment length without a repeater 100m (328ft.)

Network Management Software

Network management and utility software is typically used by network administrators and information systems personnel.

Main factors that define each type of Network cards (NIC) ?

Network transmission protocol: Ethernet Type of transmission medium: wire, radio signals, or optical fiber Data transmission speed

how noise is measured?

Noise is measured in millivolts (mV) or decibel millivolts (dBmV) over a period of time, and is usually categorized as low-, medium-, or high-frequency.

OS Software categories:

Peer-to-peer . networking software A network OS (NOS)

NEBS standards to meet

Persona; and equipment safety Equipment installation Equipment operation

Types of networks

Personal Area Network (PAN) Local Area Network (LAN) Campus Area networks ) (CAN) Metropolitan Area Network (MAN) Wide Area Network (WAN) Global Area Network (GAN)

Optical Receiver includes

Photodetector that converts the light pulses into electric signals Amplifier, if needed Message decoder

What components are common to all computer systems? (Check all that apply.)

Processor Memory Storage I/O

Fiber Optic connectors types:

ST connectors are bayonet mounted SC connectors stick and click into the device LC connectors are similar to SC connectors but smaller FC connectors screw into the device

what Communication and management software includes?

Security utilities are designed to prevent unauthorized network access, or prevent damage to an organization's information assets. Management tools are used to organize the network's structure, troubleshoot problems, and forecast the effects of design changes. Remote access services allow authorized off-site users to securely connect to the corporate LAN. Backup and recovery utilities allow an administrator to automatically run a complete system backup when the network is unused or lightly used, often in the middle of the night.

Client/Server

Servers can provide resources that clients need, such as processing power, or access to peripheral devices or special applications. The client process initiates an interaction by issuing a request to the server. The server process responds with a reply satisfying the request.

characteristic of Full-duplex communication

Signals may flow in both directions simultaneously. A telephone is the best example of full-duplex communication.

characteristic of Half-duplex communication

Signals may flow in either direction, but not simultaneously. For example, a two-way radio

A NIC is a device used for?

Signiling

Bus Topology

Simplest network designs and the firts topology used in LANs. is a single electrical cable to wich all devices in the network are conncected .

Application Software Basic categories:

Single-user applications and networked or multiuser applications. Some applications run primarily as single-user applications. "pure" networked applications, or client/ server applications, that assume they will always be used by multiple users.

advanage of start topoligy over bus topologgies

Some hubs have features that can detect defective cables and devices. Nodes are easily added and removed from a network. Network problems are easier to troubleshoot because suspect nodes can easily be disconnected from the hub.

What is it means that RAM is volatile?

That it needs a constant supply of electricity to hold data.

ANSI

The American National Standards Institute publishes standards for many types of industries, including data communications, programming languages, magnetic storage media, office systems, and encryption

IETF

The Internet Engineering Task Force

NEC

The National Electric Code

NSF

The National Science Foundation

The TIA/EIA-568 Standard

The Telecommunications Industry Association (TIA) and Electronic Industries Association (EIA)

Cable Convergence

The ability to preinstall a cabling plant is based on the fact that twisted pair or optical fiber cable can support all major LAN technologies.

data bus size

The number of data bits a CPU can work on in a single instrucction.

Examples of cloud networks

The public telephone system and the Internet are two well-known examples of cloud networks.

Twisted pair cable types:

Unshielded twisted pair (UTP) Shielded twisted pair (STP) Screened twisted pair (ScTP)

The 5/4/3 Rule

Up to five segments can be connected in a series between transmitter and receiver. Up to four signal-repeating devices (repeaters, hubs, bridges, or switches) may be used to connect segments. A maximum of only three segments can contain Ethernet nodes.

Independent Computing Architecture

Virtual Desktop

To preserve accurate data communication what parameters nust be maintained as a bit stream is transmitted on a line?

Voltage buildup must be avoided. Timing circuits must be kept synchronized with the bit stream. The signal must be strong and clear enough for the receiving devices to interpret it accurately.

M1L5 When is UTP cable preferred over STP?

When there is little electrical interference

what is attenuation?

as a signal travels along a conductor, it loses strength, or amplitude.

Vertical (Backbone) Cabling

because it often runs from an equipment room in the basement to a wiring closet on an upper floor. Vertical cabling interconnects equipment in the building entrance, equipment room, and wiring closets.

Local Area Network (LAN)

can range from a few nodes in a home office, to several hundred nodes in a corporation. However, a LAN is typically confined to a single building.

Equipment Room

centralized equipment room to provide a controlled environment for devices such as the telephone system PBX, banks of modems, servers, and internetworking equipment. In terms of structured LAN wiring, this room includes a main crossconnect, sometimes referred to as a main distribution frame (MDF). The MDF provides a central interconnection point for the network cabling.

Electrostatic discharge (ESD)

commonly known as "static electricity," is another common source of noise. ESD can also damage sensitive electronic devices.

Digital Transmission

digital signals are transmitted in the form of binary bits: information represented as a series of 1s and 0s.

Horizontal Wiring

connects the wiring closet on each floor to wall plates within each user's work area.

Campus Area Network (CAN)

consist of LANs connected across multiple buildings, using transmission links owned by the company that owns the network.

Star Topology

consists of multiple computers attached to a central signal-distributing device.

A "pure" ring topology

consists of nodes connected in a series of point-to-point links, just as people join hands in a circle.

What software do?

controls the hardware that makes communications possible.

Light source

converts the digital electrical signal to light pulses.

Encoder

converts the inout data signal into digital electrical pulses.

Connector

couples the light source to the fiber through which the light rays travel.

IEEE 802.3

defines Ethernet networks

IEEE 802.11

defines wireless networks

sources of noise

fluorescent lights, light dimmers, alternating current (AC) lines, intercoms, computers, copiers, printers, medical equipment (often an extremely high source), radios, televisions, motors, welders, and high-capacity switches.

frequency modulation

hold the amplitude constant and vary the frequency within a fixed range

Amplitude modulation

hold the frequency constant and vary the amplitude

Operating System (OS)

is a suite of software programs that provides the basic functions of a computer, such as reading and writing files, running applications, and managing I/O. When an application needs to perform one of these jobs, it makes a request to the OS.

terminator

is an electrical resistor that essentially absorbs the signal energy to prevent the signal from reflecting back from the end of the wire.

ITU (International Telecommunication Union)

is an intergovernmental organization that develops international telecommunication standards. ITU standards, called "recommendations,

star ring topology

is built by combining ring and star topologies to obtain a reliable and serviceable configuration. A wire runs from each node to a central ring wiring hub, also called a multistation access unit (MAU) by IBM.

Network Cloud

is not really a single topology. It is a representation of an unknown network structure, typically a transmission service offered by a networking service provider, such as a telephone company.

What does the term "storage" describes?

is used to decribe media that hold data for a longer periods.

Where is the NIC located in a PC?

it fits into a slot on the motherboard that is connected to the computer bus (I/OBus)

Types of light sources

light emitting diodes (LEDs) Laser transmitters

Punch Down Blocks

refer to correctly connecting each individual wire at each punch-down block and connector.

Amplitude

refers to the height of a wave, or how far from the center a wave swings.

Frequency

refers to the number of times per second a wave swings back and forth in a cycle from its beginning point to its ending point.

Physical topologies

show details about a network's connectors, cabling, and wide area links.

SNR

signal to noise ratio

Personal Area Networks (PAN)

small and local. PANs connect by means of Bluetooth wireless and can connect phones, tablets, mice, keyboards, and more.

What is bandwidth?

the information-carrying capacity of a transmission path

How is bandwidth measured?

the number of bits it can carry per second. kilobits (Kbps), megabits (Mbps), and gigabits (Gbps).

on a i/0 bus what does the term "banwidth"discribes?

the overall data carrying capacity of the bus

What does topology refer to?

the physical arrangemnt of wires, connectors, and oothers devices that connect a group of communicating nodes.

DC Resistance

the property of a conductor that opposes the flow of electrical current. It is measured in ohms, increases with cable length, and is inversely proportional to cable diameter.

Cable length tester

time-domain reflectometer (TDR)

Peer-to-Peer process

two processes have roughly the same power and can perform approximately the same services for each other.

coaxial cable

typically consists of a central copper or copper-coated conductor surrounded by flexible insulation, a shield of copper wire mesh, and an outer plastic jacket.

Manchester encoding

used for 10Base-T Ethernet LANs provides a voltage change within every 1-bit period of time.