Chapter 3 in PowerPoint for Windows format - Dr. Huang's Classes

qualtaghblurtingMobile - Wireless

Dec 12, 2013 (3 years and 7 months ago)

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Albert Huang




Network Nodes


Network nodes are devices on the network. Each of
these devices provide a specific function for the
network, network users and administrators.

Network Technology




Computers


This includes workstations used by network users or
servers


Servers are computers that serve other computers or
users. Typical servers include: file servers, print
servers, media servers, etc.


Network Printers


Allow network users to share the printing service

Nodes on the Network




Network Storage
Devices


Such as NAS


Network Attached Storage


Such as a shared DVD drive


Nodes on the Network




Network media provide the connections between the
nodes.


Network media allow the transmission of data
between network nodes


Media category:


Wired


Wireless


Network Media




Copper wires


Network Media




Coaxial Cables



Network Media




Wireless


Radio wave


e.g., AM/FM radio networks


Micro wave




e.g., WIFI


Infrared wave


e.g., TV remote control


There are computer networks that use infrared wave to
avoid EMI, in settings such as power plants.

Network Media




Waves are different in lengths and frequencies


Network Media




Devices that allow multiple cables or wireless
channels to connect and perform high
-
speed
interchange of data

Network Connection
Device




Switch


Allow incoming data to be transmitted
to only cables connected to the
destination node.


It is normally used within an
organization.


For example, the ESB Computer lab has
32 computers connected to a switch.


The switch is then connected to the
campus backbone (high bandwidth
cable that connect the different
buildings on campus)


Network Connection
Device




Routers
-

a
device that directs
network traffic, based on IP
(Internet Protocol) addresses. It is
the fundamental building block of
the Internet
.


Routers are used between two
networks on the Internet


Routers select the most efficient
route for the incoming data to be
transmitted to the destination
nodes


Network Connection
Device




Networks can be organized as


Client
-
Server


Peer
-
to
-
Peer

Network Structure




On a client
-
server network


There are computers configured as “servers”


Servers provide services to other computers


Server services include: network management, file
storage, application programs, printing service, web
services, and others.


Computers that receive services from the servers are
“clients”


A computer can server as a server and client at the
same time

Client
-
Server Network




Client
-
Server Network




For example, when you log into a computer on
campus, the ID and password is sent to the network
management server where they are verified. If the ID
and password were correct, the login would be
successful.


An example of a file server is the U: drive


where
users may store files on a central location.


A client server network could have multiple servers
serving different functions.

Client
-
Server Network




Networks where
most of the computers
operate as both
clients and servers are called peer
-
to
-
peer networks.
There is not a central server on a P2P network
.


For example, on a P2P network, there is not a network
management server that manage the users (IDs and
passwords).


Example of a P2P network:


Connecting an
iPad

and a computer together to exchange
files.


Connecting 2 or more devices together using Bluetooth to
exchange files.


Connecting multiple computers together using a home
router.


Peer
-
to
-
Peer Network




A hub is a device that
allow multiple cables
to be plugged in for
connection. Incoming
traffics (data) are
broadcasted to all
nodes.

Peer
-
to
-
Peer Network




Protocols: communication standards


Internet Protocol is TCP/IP


Transmission Control
Protocol/Internet Protocol


Currently, most computers are using IP V4. Many
networks are starting to use IP V6.

Internet Protocols




An example of an IP V4 address


138.9.1.23

IP V4




A
system that convert a domain name into an IP
address to help find the resource.


For example, when you type UOP
’s domain name
uop.edu

on a browser, the domain name is sent to
the DNS server and converted to the IP address of
the computer that hosts UOP’s web site. The IP
address is then used to find the computer and
retrieve the web pages from it.


Domain Name
Systems




Try the followings on WHOIS.NET


Search UOP.EDU


Search PACIFIC.EDU


Go to
http://
ip
-
lookup.net/domain.php


Search UOP.EDU and PACIFIC.EDU

Find the IP address for a
Domain




Bluetooth:


It
has a range of 10
-
30 feet and a maximum bandwidth of 1
mbps
.


WiFi


Wireless
Fidelity
-

a wireless standard (802.11) that provides
a theoretical bandwidth of 54 Mbps, with a range of up to
several hundred feet. Mostly used at homes or offices
.


4G


WiMax


WiMax

is a relatively new technology that is designed to
transfer wireless data over relatively long distances. A
broadband wireless access. (approximately 30
-

40 Mbps
)


LTE
(approximately 75 Mbps)

Major Wireless
Standards




It is an Internet
-
like network built for internal use only.


You may browse a company’s internal Web site, send
internal email, and perform other Internet functions.


Intranet is not accessible by outsiders.


Advantage: private and secure. It uses the same
technology used on the Internet. Users and technicians do
not need to learn a different technology. Hardware and
software are available easily.

Intranet




Similar to the Intranet, except it is built for several
organizations. For example, an extranet may be built
for your company, your suppliers, and your clients.


Users in these organization can browse your extranet
sites that are not available to outsiders.

Extranet




Where to put your Web resources?


In
-
house: maintain both the hardware and software
inside your organization.


Hosting: store your Web site on a vendor’s Web
server. The vendor takes care of the hardware and
server software maintenance. You maintain the data
and documents.


Co
-
location: maintain and own your hardware and
software; but store the entire systems on a vendor’s
facilities. Vendor provides the space, power, air
conditioning, and a high
-
speed connection.

Hosting of Web Servers




http://Goddady.Com



http://
www.1and1.com



http://
www.svcolo.co
m/index.php



Hosting & Co
-
Location