Download Slide 1

Slide 1
Chapter
6
Telecommunications and Networking
Well, Sort-of
Slide 2
Chapter
6
Telecommunications and Networking
What is Telecommunications??
 The exchange of information in any form (voice, data,
text, images, audio, video) over networks
Slide 3
Chapter
6
Telecommunications and Networking
What Types of Telecommunications are there??
• Local Area Network (LAN): networks connecting information
processing devices within a limited physical area
 Star: ties end user computers to a central computer (hierarchical)
 Ring: ties local computer in a relatively equal basis
 Bus: computers share the same communications channel
Slide 4
Chapter
6
Telecommunications and Networking
What Types of Telecommunications are there??
• Wide Area Network (WAN): networks that covers a large
geographic area
Slide 5
Chapter
6
Telecommunications and Networking
What Types of Telecommunications are there??
• Virtual Private Network (VPN): secure
network that uses the Internet as its main
backbone network, but relies on network
firewalls, encryption, and other security
features of its Internet and intranet
connections and those of participating
organizations
• Client Server Networks: PCs and
workstations, called clients are
interconnected by local area networks
and share application processing with
network servers
Slide 6
Chapter
6
Telecommunications and Networking
What Types of Telecommunications are there??
• Network Computing: Thin clients
provide a browser-based user interface
for processing small application
programs
 A thin client, sometimes also called
a lean client, is a computer (client)
in client-server architecture
networks which depends primarily
on the central server for processing
activities.
Slide 7
Chapter
6
Telecommunications and Networking
What Types of Telecommunications are there??
• Peer-to-Peer: file-sharing software
connects each PC to a central server
or to another online user’s PC
 A pure peer-to-peer network does not
have the notion of clients or servers, but
only equal peer nodes that simultaneously
function as both "clients" and "servers" to
the other nodes on the network.
 Some networks and channels use a
client-server structure for some tasks (e.g.
searching) and a peer-to-peer structure
for others.
Slide 8
Chapter
6
Telecommunications and Networking
What are the components of a Telecommunications System?
• Terminals: any input/output device that uses
telecommunications networks to transmit or receive data
• Telecommunications Processors: devices that perform
control and support functions
 Include:
• Modems
• Switches
• Routers
• Others
Slide 9
Chapter
6
Telecommunications and Networking
What are the components of a Telecommunications System?
• Telecommunications Processors:
 Modems (MOdulation-DEMolulation):
convert digital signals from a computer into
analog frequencies that can be transmitted
over ordinary telephone lines
Slide 10
Chapter
6
Telecommunications and Networking
What are the components of a Telecommunications System?
• Telecommunications Processors:
 Multiplexers: allows a single communications channel to carry simultaneous
data transmissions from many terminals
 Switches: makes connections between
telecommunications circuits in a network
 In a telecommunications network, a switch is a device that
channels incoming data from multiple input ports to the
specific output port taking data to its intended destination.
 Regular telephone services rely on circuit switching where
a switch opens a link between a sender and receiver
Slide 11
Chapter
6
Telecommunications and Networking
What are the components of a Telecommunications System?
• Telecommunications Processors:
 Switching alternatives:
 Message Switching: a message is
transmitted a block at a time from one
switching device to another
 Packet Switching: messages are divided
into fixed or variable length packets, and
packets are sent across networks
 Cell Switching: breaks voice, video and
other data into fixed cells of 53 bytes and
routes them to their next destination in
the network
Slide 12
Chapter
6
Telecommunications and Networking
What are the components of a Telecommunications System?
• Telecommunications Processors:
 Router: intelligent communications
processor that interconnects
networks based on different
protocols
Slide 13
Chapter
6
Telecommunications and Networking
What are the components of a Telecommunications System?
• Telecommunications Processors:
 Hub: a port switching communications
processor
 a device for connecting multiple twisted
pair or fiber optic Ethernet devices
together, making them act in unison
 Gateway: connects networks using
different communications architectures
 a network node equipped for
interfacing with another network that
uses different protocols.
Slide 14
Chapter
6
Telecommunications and Networking
What are the components of a Telecommunications System?
• Telecommunications Channels: media over
which data are transmitted and received
 Twisted Wire: copper wire twisted into pairs
 From 2M bits/Second (BPS) (unshielded) to
100M BPS (Shielded)
 Coaxial Cable: sturdy copper or aluminum wire
wrapped with spacers to insulate and protect it
 From 200Mbps to 500Mbps
 Fiber Optics: one or more hair-thin filaments of
glass fiber wrapped in a protective jacket
 Up to Trillions BPS (Tbps)
 ½ inch cable can carry 500,000 Channels
 Future: Each fiber can be split into 1,000 channel
Slide 15
Chapter
6
Telecommunications and Networking
What are the components of a Telecommunications System?
• Telecommunications Channels:
 Bandwidth: Classification of communications speed and
capacity of telecommunications networks
 Narrow Band: low-speed (BPS)
 Broadband: High-speed (BPS)
Slide 16
Chapter
6
Telecommunications and Networking
What are the components of a Telecommunications System?
• Wireless Telecommunications Channels:
 Terrestrial Microwave: earthbound
microwave systems that transmit highspeed radio signals in a line-of-sight
path between relay stations spaced
approximately 30 miles apart
 Communications Satellites: highearth orbit communications satellites
placed in stationary geosynchronous
orbits
Slide 17
Chapter
6
Telecommunications and Networking
What are the components of a Telecommunications System?
• Wireless Telecommunications Channels:
 Cellular and PCS Systems: a geographic
area divided into cells with one low-power
transmitter device per cell used to relay
calls from one cell to another
 Wireless LANs: high- or low-frequency
radio technology installed in an office or
building
 Wireless Webs: wireless, Web-enabled
information appliances accessing the
Internet, intranets and extranets
Slide 18
Chapter
6
Telecommunications and Networking
What are the components of a Telecommunications System?
• Telecommunications Control Software: programs that control
telecommunications activities
 Traffic Management: manage network
resources and traffic to avoid congestion
and optimize telecommunications service
levels to users
 Security: provide authentication, encryption,
firewall, auditing and enforcement
Slide 19
Chapter
6
Telecommunications and Networking
What are the components of a Telecommunications System?
• Telecommunications Control Software:
 Network Monitoring: troubleshoot and watch
over the network, informing network
administrators of potential problems before
they occur
 Capacity Planning: survey network
resources and traffic patterns and users’
needs to determine how best to
accommodate the needs of the network
as it grows and changes
Slide 20
Chapter
6
Telecommunications and Networking
What are Network Architectures & Protocols??
• Protocols: standard set of rules and procedures for the control of
communications in a network
• Network Architecture: the use of standard protocols, standard
communications hardware and software interfaces and the
design of a standard multilevel interface between end users and
computer systems with the goal of promoting an open, simple,
flexible, and efficient telecommunications environment
Slide 21
Chapter
6
Telecommunications and Networking
What are Network Architectures & Protocols??
• Open Systems Interconnection
(OSI): model is a seven-layer model
that serves as a standard model for
network architectures
• Transmission Control Protocol /
Internet Protocol (TCP/IP): is a five
layer telecommunications protocol
used by the Internet
Slide 22
Chapter
6
Telecommunications and Networking
How are telecommunications applied??
• Business Uses of the Internet:
Slide 23
Chapter
6
Telecommunications and Networking
How are telecommunications applied??
• Business Value of the Internet:
Slide 24
Chapter
6
Telecommunications and Networking
How are telecommunications applied??
• Intranet: A network inside an
organization that uses Internet
technologies to provide an
Internet-like environment within
the enterprise for information
sharing, communications,
collaboration, and the support
of business processes
 Includes firewall for security
Slide 25
Chapter
6
Telecommunications and Networking
How are telecommunications applied??
• Extranet: Network links that use Internet technologies to
interconnect the intranet of a business with the intranets of its
customers, suppliers, or other business partners
Slide 26
Chapter
6
Telecommunications and Networking
How are telecommunications applied??
• Business Value of Telecommunications:
Slide 27
Chapter
6
Telecommunications and Networking
What are the trends in Telecommunications??
• Open Systems: Information systems that use common
standards for hardware, software, applications, and networking
• Connectivity: The ability of networked computers and other
devices to easily access and communicate with each other and
share information
• Interoperability: The ability of an open system to enable the
many different applications of end users to be accomplished
using the different varieties of computer systems, software
packages, and databases provided by a variety of
interconnected networks
Slide 28
Chapter
6
Telecommunications and Networking
What are the trends in Telecommunications??
• Digital Network Technologies: Digital transmission
technologies that transmit information in the form of discrete
pulses
• Benefits:
 Higher transmission speeds
 Movement of larger amounts of information
 Greater economy
 Lower error rates
Slide 29
Chapter
6
Telecommunications and Networking
What are the trends in Telecommunications??
Slide 30
Chapter
6
Telecommunications and Networking
QUESTIONS???