Transcript jgunders_Sem_1v2_Ch_1

Sem 1v2 Chapter 1: The Basics of Computing
There are three reasons why it is important to be able to
recognize and name the major components of a PC.
First, computers are important network-building devices.
Second, many networking devices are themselves specialpurpose computers, with many of the same parts as "normal"
PCs.
Finally, in order for you to view the online curriculum, your
own computer must be in good working order.
Small, Discrete Components
•transistor •integrated circuit •resistor •capacitor •connectors (many
kinds) •light emitting diode (LED) •solder
Personal Computer Subsystems
•printed circuit board (pcb) •CD-ROM drive •CPU •floppy disk drive
•hard disk drive •microprocessor •motherboard •bus •RAM •ROM
•system unit •expansion slot •power supply
Back Plane Components
•back plane •network card •video card •sound card •parallel port
•serial port •mouse port •monitor connector •power cord
Following are some of
the important
information flows
•Boot instructions - stored in ROM, until they are sent out •software
applications (e.g. floppy disk, hard disk, CD-ROM drive, NIC card) - after
they have been loaded, are stored, temporarily, in RAM
•RAM and ROM - constantly talk to the CPU via the bus
•Application information - stored in RAM as long as the application is
being used.
•Saved information - flows from RAM to some form of storage device
•Exported information - flows from RAM and the CPU, via the bus and
expansion slots, to the serial port, parallel port (usually for printers), video
card, sound card, or network card
A network interface card (NIC) is a printed circuit board that provides
network communication capabilities to and from a personal computer. Also
called a LAN adapter it plugs into a motherboard and provides a port for
network connection.
This card can be designed as an Ethernet card, a token-ring card, or an
Fiber Distributed Data Interface (FDDI) card.
A network card communicates with
the network through a serial
connection, and with the computer
through a parallel connection. Each
requires an IRQ, an I/O address,
and an upper memory address for
DOS and for Windows 95/98
In order to perform the
installation of a NIC
card you should have
the following resources:
•knowledge of how the network card is usually configured, including
EPROM, jumpers, and plug-and-play software
•use of network card diagnostics, including the loopback test and vendorsupplied diagnostics
•ability to resolve hardware resource conflicts, including IRQ, DMA, and I/O
Base Address
The expansion slots of laptops because of their size necessarily
become PCMCIA slots, where NICs, modems, hard drives and
other useful devices – usually the size of a thick credit card - can
be installed/inserted in various places along the perimeter.
After you have set up the PC
hardware you must configure its
software. You must complete the
following tasks in order to be able
to view the curriculum:
1.select the NIC
2.set the correct IP
address
3.adjust the display (if
necessary)
4.install and set up the
browser
5.perform a few other
tasks (if necessary)
This introduces the importance
of IP Addressing and subnet
masking. There is no need to
explain them in detail -something along the lines of
"every computer needs an address
to participate in the Internet".
Some labs will have statically
configured IP addresses, in
which case the students can
actually view their IP address;
others will have DHCP and will
need to run winipconfig to view
their dynamically assigned
address.
A web browser acts on behalf of a user by contacting a web
server, requesting information, receiving information, and then
displaying the results on a screen. A browser is software that
interprets hypertext markup language (HTML) which is the
language used to code web page content. HTML can display
graphics, play sound, movies, and other multimedia files.
Hyperlinks - computer program commands that point to other places inside a PC, or
on a network - connect to other web pages and to files that can be downloaded.
Troubleshooting is an essential concept on the CompTIA
standards and will be woven through all four semesters of
curriculum.
The purpose of this target indicator is to have students realize that
networking grew out of particular communications needs, but that as
it grew standards were required
LANs make it possible for businesses that use computer
technology to share, efficiently, such items as files and printers,
and to make possible communications such as e-mail. They tie
together data, communications, computing, and file servers.
Some common WAN technologies are:
•modems •ISDN (Integrated Services Digital Network) •DSL
(Digital SubscriberLoop) •frame relay •ATM (Asynchronous Transfer Mode)
•T-Carrier Series (in U.S.:T1, T3, etc.) •SONET (Synchronous Optical
Network)
Information - text, pictures, movies, audio, video, anything - can be
represented by binary codes (i.e. binary digits, bits, 1s and 0s).
Advances in microelectronics, computer design, software, and
networking now make it possible to codify almost any
information, then transmit it from any place to any place, at
approximately the speed of light
You will spend much time during the CCNA program studying
how this is possible.
The fundamental unit of bandwidth -- a unit of information
(lets say the bit) per unit of time (lets say a second) is the bit per
second, a rate, a flow.
No matter how you send your messages, no matter which physical
medium you use, bandwidth is limited. This is due both to the
laws of physics and to current technological advances.
Throughput usually refers to
actual, measured,
bandwidth, at a specific time
of day, using specific
internet routes, while
downloading a specific file.
Some of the factors that
determine throughput and
bandwidth include the
following:
•internetworking devices •type of data being transferred •topology
•number of users •user's computer •server computer •power and
weather-induced outages •and many other reasons.
An important part of networking involves making decisions
about which medium to use. This often leads to questions
regarding the bandwidths that the user's applications require.
The graphic summarizes a simple formula that will help you
with such decisions
The End