Transcript Telecommunications and Networking - University of Baltimore Home

 Case 2/p128
BLOG
(web+log)
source: http://en.wikipedia.org/wiki/Blog#Types_of_blogs
 A blog is a user-generated website where
entries are made in journal style and
displayed in a reverse chronological order.
 Blogs often provide commentary or news on
a particular subject, such as food, politics, or
local news; some function as more personal
online diaries
 Youtube type of a video weblog
Myspace
source: http://en.wikipedia.org/wiki/MySpace
 MySpace is a social networking website
offering an interactive, user-submitted
network of friends, personal profiles, blogs,
groups, photos, music and videos. MySpace
also features an internal search engine and
an internal e-mail system
Drawing money from an ATM
Telecommunications
and Networking
Learning Objectives
1. Understand the concept of a network.
2. Apply Metcalfe’s law in understanding the
value of a network.
3. Identify several major developments and
trends in the industries, technologies, and
business applications of
telecommunications and Internet
technologies.
4. Examples of the business value of Internet,
intranet, and extranet applications.
Learning Objectives
5. Identify the basic components, functions,
and types of telecommunications networks
used in business.
6. Explain the functions of major components
of telecommunications network hardware,
software, media, and services.
7. Explain the concept of client/server
networking.
8. Understand the two forms of peer-to-peer
networking.
Learning Objectives
10.Identify the various transmission media
and topologies used in telecommunications
networks.
11.Understand the fundamentals of wireless
network technologies.
12.Explain the concepts behind TCP/IP.
13.Understand the seven layers of the OSI
network model.
Network Concepts
 Network
– An interconnected chain, group or system
 Number of possible connections on a
network is N * (N-1)/2
– Where N = number of nodes (points of
connections on the network)
– Example, if there are 10 computers on a
network, there are 10 * 9/2 = 45 possible
connections
Telecommunications
 Telecommunications
– Exchange of information in any form (voice,
data, text, images, audio, video) over networks
Basic concepts
 Communication protocols (TCP/IP)
 Data transmission methods
– Asynchronous
– Synchronous
 Connecting
– Modem
– Hardwired and remote
 Data transmission channels (bps)
– narrow bands: 5-30
– voice bands: 1,000-9,600
– broad bands: 100,000
 Types of communication lines
– simplex
– half-duplex
– duplex
Networks
 Concept
– "a group of interconnected computers, workstations, or computer devices
(such as printers and data storage systems).”
 Network topology
– bus
– star
–
ring
 Local-area networks
– bus: Ethernet, carrier sense multiple access (CSMA)
– ring: token passing method
 Distributed data processing
– "interconnects sites of one organization not only for communication of data
and messages but also for
the sharing of resources."
Open Systems
 Information systems that use common standards
for hardware, software, applications and networks
 Internet networking technologies are a common
standard for open systems
 Connectivity:
– Ability of networked computers to easily access and
communicate with each other and share information
 Interoperability:
– The ability of an open system to enable end user
applications to be accomplished using different
varieties of computer systems, software packages,
Middleware
 Any programming that serves to “glue
together” two separate programs
Internet2
 Next generation of the Internet
 High-performance network
 In use at 200 universities, scientific
institutions, communications corporations
Internet Service Provider
 ISP
– A company that specializes in providing easy
access to the Internet
– For a monthly fee, you get software, user name,
password and access
 ISPs are connect to one another through
network access points
An Intranet Also look at fig 6.8
 A network inside an organization
– That uses Internet technologies (such as Web
browsers and servers, TCP/IP protocols, HTML,
etc.)
– To provide an Internet-like environment within
the organization
– For information sharing, communications,
collaboration and support of business
processes
– Protected by security measures
– Can be accessed by authorized users through the Internet
Extranet (also look at fig 6.9)
 Network links that use Internet technologies
– To connect the Intranet of a business
– With the Intranets of its customers, suppliers or
other business partners
GPS
1. The global positioning system (GPS) is a major
technological achievement that has broadreaching implications for business. Using the
Internet,
– Can find other innovative uses for GPS.
– Good places to start familiarizing yourself with
current accomplishments are

The GPSWorld site at
http://www.gpsworld.com/gpsworld/
 The GPS Overview at
http://www.colorado.edu/geography/gcraft/notes/gps/g
ps_f.html
Telecommunications network
 Any arrangement where a sender transmits
a message to a receiver over a channel
consisting of some type of medium
Types of Networks




WAN
LAN
VPN
C/S
VPN
 Basically, a VPN is a private network that uses a
public network (usually the Internet) to connect
remote sites or users together. Instead of using a
dedicated, real-world connection such as leased
line, a VPN uses "virtual" connections routed
through the Internet from the company's private
network to the remote site or employee.
Source: computer.Howstuffworks.com
VPN
Internetwork Processors
 Switch – makes connections between
telecommunications circuits in a network
 Router – intelligent communications
processor that interconnects networks
based on different protocols
 Hub – a port switching communications
processor
 Gateway – connects networks using
different communications architectures
ROUTERS
Routers are specialized computers that send
your messages and those of every other
Internet user speeding to their destinations
along thousands of pathways.

Fujitsu GeoStream R980 industrial strength router
ROUTERS
configuration table. A configuration table is a collection of
information, including:
 Information on which connections lead to particular groups
of addresses
 Priorities for connections to be used
 Rules for handling both routine and special cases of traffic
A router, then, has two separate but related jobs:
 The router ensures that information doesn't go where it's
not needed. This is crucial for keeping large volumes of
data from clogging the connections of "innocent
bystanders."
 The router makes sure that information does make it to the
intended destination.
Computer.howstuffworks.com
Distributed data processing
TSS - Time Sharing Systems
PC
PC
PC
MAINFRAME
CSS - Client Server Systems
PC
Client/Server networks
 Clients: End user personal computers
or networked computers
 Interconnected by LANs
 Servers: manage networks
 Processing shared between clients and
servers
CSS architecture
Remote
Server
File
Server
Communications Server
Print
Server
LA N
PC
PC
PC
PC
Peer-to-peer networks (p 209)
 Networks that connect from one PC to another PC
Peer-to-peer networking enables or enhances the
following scenarios:
 Real-time communications (RTC)
 Collaboration
 Content distribution
 Distributed processing
 Improved Internet technologies
Source: www.microsoft.com
Wireless Technologies
 Terrestrial microwave
– Earthbound microwave systems that transmit
high-speed radio signals in a line-of-sight path
– Between relay systems spaced approximately
30-miles apart
 Communications satellites
– Satellite serves as relay stations for
communications signals
– Uses microwave radio signals
Wireless Technologies
 Cellular and PCS telephone and pager
systems
– Divide the geographic area into small areas or
cells
– Each cell has transmitter or radio relay antenna
to send message from one cell to another
 Wireless LANs
– Radio signals within an office or building
– Connect PCs to networks
 Bluetooth
Bluetooth
 Bluetooth is a standard developed by a group of
electronics manufacturers that allows any sort of
electronic equipment -- from computers and cell
phones to keyboards and headphones -- to make
its own connections, without wires, cables or any
direct action from a user.
 Bluetooth can connect up to eight devices
simultaneously. With all of those devices
in the same 10-meter (32-foot) radius
http://www.dell.com/content/topics/topic.aspx/
global/shared/corp/media/en/studio_dell?c=
us&l=en&s=corp&targetNetwork=2&targetC
hannel=4&targetMedia=32
Steps in wireless network
source: www.dell.com
Cell Phones
source: howstuffworks.com
GSM (CDMA) vs TDMA
TDMA (time division multiple access) assigns each call a certain
portion of time on a designated frequency.
Works on either the 800-MHz or 1900-MHz frequency bands.
CDMA (code division multiple access) gives a unique code to each
call and spreads it over the available frequencies.
GSM operates in the 900-MHz and 1800-MHz bands in Europe and Asia
and in the 850-MHz and 1900-MHz (sometimes referred to as 1.9-GHz)
band in the United States
 Cell vs Mobile
Band/Mode
Multiple band - A phone that has multiple-band capability can
switch frequencies. For example, a dual-band TDMA
phone could use TDMA services in either an 800-MHz or a
1900-MHz system. A quad-band GSM phone could use
GSM service in the 850-MHz, 900-MHz, 1800-MHz or
1900-MHz band.
Multiple mode - In cell phones, "mode" refers to the type of
transmission technology used. So, a phone that
supported AMPS and TDMA could switch back and forth as
needed. It's important that one of the modes is AMPS -this gives you analog service if you are in an area that
doesn't have digital support.
EDI Concepts
 EDI is a mechanism for electronic trading
 EDI replaces paper flow with online transactions
 EDI architecture
 EDI is for trading partners
 Implementation plan is a key factor
 Obstacles:

– lack of transaction standardization
– high start-up costs
EDI third-party suppliers
– AT&T, Control Data, EDS, GE, Western Union, IBM, Martin Marietta
Data Systems, etc.
EDI architecture
Trading Partner 1
Trading Partner 2
CONFIRMATION
standard
transactions
Transaction
Converter
Transaction
Converter
Acquisition System
system
transactions
system
transactions
CONFIRMATION
Order Entry System
ORDER
ORDER
Network Topologies (p 219)
Topology: structure of a network
 Star: ties end user computers to a central
computer
 Ring: ties local computer processors
together in a ring on a relatively equal basis
 Bus: local processors share the same
communications channel
Network Architectures &
Protocols
 Protocol: standard set of rules and
procedures for the control of
communications in a network
 Network Architecture:
– Master plan of standard protocols, hardware,
software and interfaces between end users and
computer systems
– Goal of promoting an open, simple, flexible, and
efficient telecommunications environment
OSI & TCP/IP Models (p 221)
 Open Systems Interconnection (OSI) Model
– A seven-layer model that serves as a standard
model for network architectures
– Model for how messages should be transmitted
between two points in a network
– Each layer adds functions
 Transmission Control Protocol / Internet
Protocol (TCP/IP)
– A five layer telecommunications protocol used
by the Internet
IP
Internet protocol
 Each system connected to the internet is identified by a 32-bit IP address
 Four numbers separated by a decimal
Each represented by octal (8 bits; hence 0-255)
 Ex: 168.212.226.204
Binary format:
10101000.11010100.11100010.11001100
A new protocol IPv6 allows for 128 bit IP addresses
to look up an IP address : http://www.kloth.net/services/nslookup.php
to find info:
http://www.geobytes.com/IpLocator.htm
Basic Communications Model
Standards are needed at all Layers
User Layer
Application Layer
Computer (Transport) Layer
Transmission Layer
Internet Telephony
 Using an Internet connection to pass voice
data using IP
 Voice over IP (VoIP)
 Skips standard long-distance phone charges
VOIP (source www.fcc.gov)
Bandwidth
 Bandwidth
– Frequency range of a telecommunications
channel
– Determines transmission rate
– Classified in bits per second (bps)
 Transmission Rates:
– Narrow-band – low-speed
– Broadband – high-speed
WiFi
 WIreless FIdelity (WiFi)-- used generically when referring
of any type of 802.11
"Wi-Fi Certified" (a registered trademark) by the Wi-Fi Alliance
are interoperable with each other,
even if they are from different manufacturers. A user with a
"Wi-Fi Certified" product can use any
brand of access point with any other brand of client
hardware that also is certified
http://www.webopedia.com/TERM/W/Wi_Fi.html
Additional Readings
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Voice over data networks
Networking Hardware Quiz
abc of wireless LAN
ISDN Tutorial
Ethernet tutorial
Internet Protocol
Thin clients
UNIX/NT integration
Cell phones