CSCI 1101 Intro to
Computers
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A computer network is a collection of
computers and other devices that
communicate to share data, hardware and software.
Local area network (LAN) - a network located
in a limited area.
found in most businesses
Wide area network (WAN) - a network that
covers a large geographical area
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A local area network makes a stand-alone
computer a workstation on a network.
The workstation provides you with:
your computer’s local resources
hard drive, software
printer
access to network resources
software
storage space
other printers
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Network nodes
include workstations printers, and
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You typically cannot use network resources
until you log into the network.
provide user ID and password
User account
provides access to network
accumulates information about network use
tracks when you log in and out
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Use these tips to select a secure password.
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Workstation gains access to the server
when the server hard drive is “mapped” to a drive letter.
Drive mapping - network term for assigning
a drive letter to a network server disk drive.
many use the letter F
Window’s Neighborhood Network is a utility
that helps you see your workstation’s network drive mapping.
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When you start a program that is stored on a LAN, the
program is copied to your workstation’s RAM, then runs normally.
With proper licensing, many users on the same
network can use the same program simultaneously, also known as sharing.
Sharing is effective because:
less disk storage space required
easier to update software
less expensive
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Advantages to storing data files on a server:
can access from any computer on network
other network users can access files
option of restricting access
File locking - precaution that locks an open
file so other users cannot open it at the same time
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Default printer -
printer you most frequently use
One way to
select a different printer is to
select a printer using the
Printers dialog box.
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A network interface card (NIC) is the key
hardware component for connecting a computer to a local area network.
small circuit board that sends data to and from
workstation to network
Different networks use different NICs.
Popular network types include Ethernet and
Token Ring.
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Today’s networks use twisted-pair cable
UTP (unshielded twisted pair
STP (shielded twisted pair)
looks similar to telephone cable
has square plastic RJ-45 connector
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Another option is coaxial cable
resembles cable-TV cable
round, silver BNC connector
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Wireless networks use radio or infrared
signals to transmit data from one network device to another.
handy in environments where wiring is difficult to
install
historical buildings
provide mobility
good for temporary installations
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On most of today’s networks, the cable from a
workstation NIC connects to a network hub, a device that joins communication lines together.
A hub serves as
a central connection point for workstation and server cables.
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When connected to a network, the device that
processes your data depends on the types of servers.
dedicated servers
non-dedicated servers
print servers
application servers
host computers
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Application server - computer that runs a
specific application software package
also referred to as client/server architecture
An application server splits processing
between the workstation (client) and the network (server).
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An application server typically runs database software and performs database functions as requested by the
workstations.
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Some networks include a host computer, a
minicomputer or a mainframe with attached terminals.
all processing takes place on the host
terminals only display results of processing also known as a time-sharing system
Cyrix processing systems use this model
Terminal emulation software connects a
microcomputer to a host
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Today’s computers include software necessary
to communicate with a network.
The software handles the communication
between your workstation and the network server.
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Network operating system (NOS) software
manages network resources controls flow of data
maintains security tracks user accounts
Network operating system has two
components
network server software network client software
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Network server software (installed on file server)
controls file access from the server’s hard disk
manages print queue
tracks user data
IDs and passwords
Network client software (installed on workstation)
gathers login information
handles drive mapping
directs printouts to network printer
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Most software designed for stand-alone
computers can be installed on a network server.
Some software has built-in networking
features that only appear when software is installed on network.
ability to send a file to another network user
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Using a single-user license for multiple users
typically violates software’s copyright.
Software publishers offer a network license
that allows use by multiple people on a network.
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Groupware is application software that supports
collaborative work by managing:
schedules
shared documents
intra-group communications
based on “information-centered model
Workflow software - automates the process of
electronically routing documents from one person to another in a specified sequence
based on a “process-centered model”
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E-mail messages
are stored on a server and
forwarded to you when you want to read it.
(store-and-forward technology)
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A gateway is an electronic link to other e-mail
systems that allows you to send e-mail to people on other networks.
transferred through the gateway
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Tips for using e-mail
read mail regularly
delete messages after you read them
you don’t have to reply to every e-mail
reply to one person instead of entire group
think before you send
don’t write anything confidential
don’t get sloppy
use proper netiquette
