SlideShare a Scribd company logo
1 of 92
Download to read offline
ECE 512L
Data Communication
Engr. Adriano Mercedes H. Cano Jr.
Electronics Engineering
College of Engineering Education
University of Mindanao - Tagum College
Course Outline
• Module 1: Data Communications
Fundamentals
– Communication model,
– Data communication network
– Standards,
– Protocol
– OSI model,
– TCP/IP,
Course Outline
• Module 2: Fundamental Concepts of Data
Communications
– Data Communications Circuits
– Data Communications Codes
– Bar Codes
– Line Control Unit
– Error Control
– Error Detection
– Error Correction
– Serial Interfaces
– Data Communications Modems
– ITU-T Modem Recommendations
– Character Synchronization
Course Outline
• Module 3: Data Link Control Protocols
– Data-Link Protocol Functions
– Character- and Bit-Oriented Data-Link
– Protocols
– Asynchronous Data-Link Protocols
– Asynchronous Transfer Mode
– Synchronous Data-Link Protocols
– High-Level Data-Link Control
– Public Switched Data Networks
– CCITT X.25 User-to-Network Interface Protocol
– Integrated Services Digital Network
– Synchronous Data-Link Control
Course Outline
• Module 4: Data Communication Networking
– Introduction to Switched Circuits
– Circuit Switching and Packet Switching
– Local Area Networks, Applications, and Architectures
• Ethernet
• Ring
• Token Ring
• FDDI
– Local Area Networks and Interconnections
• Repeaters
• Bridges and Switches
• Routers and Gateways
– The Internet
• Overview of the Internet
• The Internet Protocol
• Domain Name Systems
• Internet Protocol Over Internet
Reference Books
• Advance Electronics Communication
– Wayne Tomasi
• Data Communications and Networking
– Behrouz A. Forouzan
Module 1:
Data Communications Fundamentals
Introduction
• Data generally are defined as information
that has been processed, organized, and is
stored in digital form
• Information is defined as knowledge or
intelligence.
• Data communications is the process of
transferring digital information (usually in
binary form) between two or more points.
Data Communication
Standards
Error detection and correction
Network Devices
Header & Trailer
Encryption
Location A Location B
Introduction
• Data Transmission
• is the transmission, reception, and
processing of digital information
• Transmission is either parallel or serial
Introduction
• Transmission Modes
– Simplex (SX) mode, data transmission is unidirectional; receive-only,
transmit-only, or one-way-only lines.
• Ex. Commercial radio broadcasting
– Half-duplex (HDX) mode, data transmission is possible in both
directions but not at the same time. Also called two-way-alternate or
either-way lines.
• Ex. Citizens band (CB) radio
– Full duplex (FDX) mode, transmissions are possible in both directions
simultaneously, but they must be between the same two stations. also
called two-way simultaneous, duplex, or both-way lines.
• Ex. A local telephone
– Full/full duplex (F/FDX) mode, transmission is possible in both
directions at the same time but not between the same two stations (i.e.,
one station is transmitting to a second station and receiving from a third
station at the same time).
• Full/full duplex is possible only on multipoint circuits.
• Ex. postal system
Data Communication 1
• Data can be propagated to the network by
either
– Segment
– packet
– frame,
Introduction
• Data communications networks
– are systems of interrelated computers and
computer equipment(called nodes) and
connected together through the public
telephone network.(media links)
– Its purpose is to transfer digital information
from one place to another.
Introduction
Data Communication 1
History of Data Communication
• 1753. One of the earliest means of
communicating electrically coded information
through a 26 wire system.
• 1833. Carl Friedrich Gauss developed a system
based on a 5x5 matrix representing 25 letters.
• 1832. The telegraph (the first data
communication system) was invented by Samuel
F.B. Morse.
• 1840. The American patent for the telegraph was
granted.
• 1844. The first telegraph line was established
between Baltimore and Washington D.C.
conveying the first telegraph message “What
hath God wrought!”
16
• 1849. The first slow-speed telegraph printer was
invented.
• 1850. Western Union Telegraph Company was
formed in Rochester, New York, for the purpose
of carrying coded messages from person to
another.
• 1860. “High-speed” printers (15 bps) became
available.
• 1874. Emile Baudot invented the a telegraph
multiplexer that allowed signals from up to six
different telegraph machines to be transmitted
simultaneously over a single wire.
• 1875. The telephone was invented by Alexander
Graham Bell.
17
History of Data Communication
History of Data Communication
• 1899. Guglielmo Marconi succeeded in sending
radio (wireless) telegraph messages.
• 1920. The first commercial radio stations carrying
voice information were installed.
• 1930s. Konrad Zuis, a German engineer,
demonstated a computing machine.
• 1940. Bell Laboratories developed the first
special purpose computer using
electromechanical relays for performing logical
operations.
• 1946. The first modern-day computer (ENIAC)
was developed by J. Presper Eckert and John
Mauchley at the University of Pennsylvania.
18
History of Data Communication
• 1949. The U.S. National Bureau of Standards
developed the first all-electronic diode based
computed capable of executing stored-programs.
• 1950s. “Batch processing” computers used
punched cards as an input interface, printers as
an output interface, and magnetic tape reels for
data storage.
The first general purpose computer in
the form of an automatic sequence-controlled
calculator was developed jointly by Harvard
University and IBM Corporation.
• 1951. Remington Rand Corporation built the first
mass-produced electronic computer (UNIVAC).
19
History of Data Communication
• 1960s. Batch-processing systems were
replaced by on-line processing systems with
terminals connected directly to the
computer through serial or parallel
communication lines.
• 1968. The landmark US Supreme Court
Carterfone decision allowed non-Bell (non
AT&T) equipment to be connected to the
vast AT&T network.
• 1969. The internet began to evolve at the
Advanced Research Projects Agency (ARPA)
through the ARPANET.
• 1970s. Microprocessor-controlled
microcomputers were developed.
20
History of Datacom
• 1980s. Personal computers became an
essential item in the home and the
workplace. Since then, the need to
exchange digital information, and
consequently, the need for data
communication circuits, networks, and
systems increased exponentially.
• 1983. AT&T agreed in a court settlement to
divest itself of operating companies that
provide basic local telephone service to
various geographic regions of the US as a
result of an anti-trust suit filed by the federal
government.
21
History of Data Communication
• Mid 1980s to 1995. The United Stated National Science
Foundation (NSF) funded a high-speed backbone called
the NSFNET.
• 1989. Tim Berners-Lee and Robert Cailliau build the
prototype system which became the World Wide Web at
CERN.
• 1991. Anders Olsson transmits solitary waves through
an optical fiber with a data rate of 32 billion bits per
second.
• 1992. Neil Papworth sends the first SMS
Internet2 organization is created.
• 1994. Internet radio broadcasting is born.
22
History of Data Communication
• 1999. 45% of Australians have a mobile phone.
Sirius satellite radio is introduced.
• 2001. First digital cinema transmission by satellite
in Europe of a feature film by Bernard Pauchon
and Philippe Binant is undertaken.
• 2003. Apple launches the iTunes Music Store and
sells one million songs in its first week.
MySpace is launched.
• 2004. What would become the largest social
networking site in the world, Facebook is
launched.
• 2005. YouTube, the video sharing site is launched.
.
23
History of Data Communication
• 2006. Twitter, microblogging is
introduced.
24
Network Architecture
Network Architecture
Design of
communication
network
is a set of layers
and protocols
outline the
products and
services
is a framework for
the specification
• General classifications:
– Current: include the most modern and
sophisticated networks and protocols
available.
– Legacy: no one really wants to use it, but for
some reason it just will not go away.
– Legendary: Old and No longer in use
Network Architecture
• can be classified in two different ways:
– Broadcast :
• messages are intended for all subscribers on the
network
• all stations and devices on the network share a single
communication channel
– Point to point:
• All transmissions from one station are intended for and
received by the other station.
– multicasting:
• when messages are intended for a specific group of
subscribers.
Network Architecture
Data Communication 1
Network Architecture
electrical specifications
hardware arrangements
software procedures
Transmission media
layers of functional responsibility
Company A A Company YA
Company BA
Company X A
Protocol
Network Protocols
sets of rules that allows two
hardware or software
processes to work together
how much data can be sent?
how it will be sent? how much data can be sent?
how it will be addressed?
what procedure will be used to
ensure that there are no undetected errors?
Network Protocols
• Protocol stack
– The list of protocols used by a system, which
generally includes only one protocol per layer
Layered Network
Architecture
Consist of two or
more independent
levels.
Each level has a
specific set of
responsibilities and
functions
data transfer,
flow control,
data segmentation
reassembly,
sequence control,
error detection and
correction,
notification
Reduce Complexity
Standardizes interfaces
Facilitates modular
engineering
Ensure Interoperable
engineering
Accelerates evolution
simplifies teaching and
learning
Connection- oriented protocol
1. Establishes handshake before any
data are actually transmitted between
two stations.
2. Require s acknowledgement of the
data as they are being transmitted.
(ensure reliability)
3. Provide some means of error control
4. When a connection is no longer
needed, a specific handshake drops the
connection.
Network Protocols
Connections are sometimes referred to
as sessions, virtual circuits, or logical
connections.
Connectionless protocol
1. Send data with a source and
destination address without a
handshake .
2. Do not support error control or
acknowledgment procedures,
making them
3. Data being transmitted usually do
not have extra overhead
Network Protocols
Connection-oriented protocol
Connectionless protocol
Network Protocols
reliability
• Syntax
– refers to the structure or format of the data within
the message, which includes the sequence in
which the data are sent.
• Ex: the first byte of a message might be the address of
the source and the second byte the address of the
destination.
• Semantics
– refers to the meaning of each section of data.
• Ex: does a destination address identify only the
location of the final destination, or does it also identify
the route the data takes between the sending and
receiving locations?
Network Protocols
Copyright 2005 John Wiley & Sons, Inc 1 - 37
Data Comm. Standards
• Standard
– is an object or procedure considered by an authority
or by general consent as a basis of comparison
• Data communications standards are not laws,
however—they are simply suggested ways of
implementing procedures and accomplishing
results
• Guidelines that have been generally accepted by
the data communications industry
Copyright 2005 John Wiley & Sons, Inc 1 - 38
Data Comm. Standards
• Importance
– Compatibility of hardware and/or software systems among
different companies
– Help promote competition and decrease the price
• Types of Standards
– Formal standards
• Developed by an industry or government standards-making
body
– De-facto standards
• Emerge in the marketplace and widely used
• Lack official backing by a standards-making body
Copyright 2005 John Wiley & Sons, Inc 1 - 39
Standardization Processes
• Specification
– Developing the nomenclature and identifying
the problems to be addressed
• Identification of choices
– Identifying solutions to the problems and
choose the “optimum” solution
• Acceptance
– Defining the solution, getting it recognized by
industry so that a uniform solution is accepted
Copyright 2005 John Wiley & Sons, Inc 1 - 40
Some Data Comm. Standards
Layer Common Standards
5. Application layer
HTTP, HTML (Web)
MPEG, H.323 (audio/video)
IMAP, POP (e-mail)
4. Transport layer
TCP (Internet)
SPX (Novell LANs)
3. Network layer IP (Internet)
IPX (Novell LANs)
2. Data link layer
Ethernet (LAN)
Frame Relay (WAN)
PPP (dial-up via modem for MAN)
1. Physical layer
RS-232c cable (LAN)
Category 5 twisted pair (LAN)
V.92 (56 kbps modem)
Copyright 2005 John Wiley & Sons, Inc 1 - 41
Major Standards Bodies
• ISO (International Organization for Standardization)
– Technical recommendations for data communication interfaces
– Composed of each country’s national standards orgs.
– Based in Geneva, Switzerland (www.iso.ch)
• ITU-T (International Telecommunications Union –
Telecom Group
– Technical recommendations about telephone, telegraph and
data communications interfaces
– Composed of representatives from each country in UN
– Based in Geneva, Switzerland (www.itu.int)
Copyright 2005 John Wiley & Sons, Inc 1 - 42
• ANSI (American National Standards Institute)
– Coordinating organization for US (not a standards- making
body)
– www.ansi.org
• IEEE (Institute of Electrical and Electronic Engineers)
– Professional society; also develops mostly LAN standards
– standards.ieee.org
• IETF (Internet Engineering Task Force)
– Develops Internet standards
– No official membership (anyone welcomes)
– www.ietf.org
Major Standards Bodies
Data Communication 1
Standards
• Proprietary
– are generally manufactured and controlled by one
company.
– Ex: Apple Macintosh.
– Advantages
• are tighter control, easier consensus, and a monopoly.
– Disadvantages
• include lack of choice for the customers, higher
financial investment, overpricing, and reduced customer
protection against the manufacturer going out of
business.
Standards
• Open System
– any company can produce compatible equipment or
software; however, often a royalty must be paid to the
original company.
– Ex: IBM’s personal computer.
– Advantages
• customer have a choice, compatibility between venders, and
competition by smaller companies.
– Disadvantages
• less product control and increased difficulty acquiring
agreement
• between vendors for changes or updates.
• In addition, standard items are not always as
• compatible as we would like them to be.
STANDARDS ORGANIZATIONS
• A consortium of organizations, governments,
manufacturers, and users meet on a regular basis to
ensure an orderly flow of information within data
communications networks and systems by establishing
guidelines and standards.
• The intent is that all data communications equipment
manufacturers and users comply with these standards.
• Standards organizations generate, control, and
administer standards.
• Often, competing companies will form a joint
committee to create a compromised standard that is
acceptable to everyone.
• Each layer adds value to services provided by sets of
lower layers.
• The highest level is offered the full set of services
needed to run a distributed data application.
• Each layer is essentially independent of every other
layer.
• Advantages
– facilitates peer-to-peer communications protocols
• where a given layer in one system can logically communicate
with its corresponding layer in another system.
• allows different computers to communicate at different levels.
• Disadvantage
– tremendous amount of overhead required
Layered network architecture
In case of more >1 destination: service access point (SAP) address is
used to define which entity the service is intended.
Protocol Data Unit
• communications between two corresponding
layers requires PDU.
• can be a header added at the beginning of a
message or a trailer appended to the end of
a message.
• As data passes from one layer into another,
headers and trailers are added and removed
from the PDU.
• The process of adding or removing PDU
information is called encapsulation
/decapsulation
Protocol Data Unit
Data Communication 1
OPEN SYSTEMS INTERCONNECTION
• In 1983, the ISO and ITU-T (CCITT)
adopted a seven-layer communications
architecture reference model.
• The primary purpose is to serve as a
structural guideline for exchanging
information between computers,
workstations, and networks.
• Each layer consists of specific protocols for
communicating.
OPEN SYSTEMS INTERCONNECTION
• was developed to facilitate the
intercommunications of data processing
equipment by separating network
responsibilities into seven distinct layers.
• As with any layered architecture, overhead
information is added to a PDU in the form of
headers and trailers.
• In fact, if all seven levels of the OSI model are
addressed, as little as 15% of the transmitted
message is actually source information, and
the rest is overhead.
Open Systems Interconnection
54
Please Do Not Touch Steve’s Pet Alligator
Open Systems Interconnection
 User networking applications and
interfacing to the network
 Encoding language used in transmission
 Job management tracking
 Data tracking as it moves through a
network
 Network addressing and packet
transmission on the network
 Frame formatting for transmitting data
across a physical communications link
 Transmission method used to propagate
bits through a network
56
LAYERS FUNCTIONS
Open Systems Interconnection
57
TCP/IP
OSI and its Protocol Data Units
ECE @Saint Louis University, Baguio City 58
Physical layer
Data Link layer
Network layer
Transport layer
Session layer
Presentation layer
• Layered network
• architectures consist of two or more
independent levels
Application layer
DoD: Department of Defense
Data Communication 1
Data Communication 1
Data Communication 1
TCP/IP
• Transmission Control Protocol/Internet
protocol
• TCP at the transport layer and IP at the
network layer
• Designed by Vinton G. Cerf and Robert E.
Kahn
• developed by the United States Defense
Advanced Research Projects
Agency (DARPAor ARPA)
TCP
• Reliable, full-duplex, connection-oriented,
stream delivery
– Interface presented to the application doesn’t
require data in individual packets
– Data is guaranteed to arrive, and in the
correct order without duplications
• Or the connection will be dropped
– Imposes significant overheads
Applications of TCP
• Most things!
– HTTP, FTP, …
• Saves the application a lot of work, so
used unless there’s a good reason not to
TCP implementation
• Connections are established using a
three-way handshake
• Data is divided up into packets by the
operating system
• Packets are numbered, and received
packets are acknowledged
• Connections are explicitly closed
– (or may abnormally terminate)
TCP Packets
• Source + destination ports
• Sequence number (used to order packets)
• Acknowledgement number (used to verify
packets are received)
TCP Segment
Destination Port
Acknowledgment Number
Options... Padding
Data...
0 4 10 16 19 24 31
Source Port
WindowLen
Sequence Number
Reserved Flags
Urgent PointerChecksum
Field Purpose
Source Port Identifies originating application
Destination Port Identifies destination application
Sequence Number Sequence number of first octet in the segment
Acknowledgment # Sequence number of the next expected octet (if ACK flag set)
Len Length of TCP header in 4 octet units
Flags TCP flags: SYN, FIN, RST, PSH, ACK, URG
Window Number of octets from ACK that sender will accept
Checksum Checksum of IP pseudo-header + TCP header + data
Urgent Pointer Pointer to end of “urgent data”
Options Special TCP options such as MSS and Window Scale
You just need to know port numbers, seq and ack are added
TCP : Data transfer
HostClient
Send Packet 1
Start Timer
Retransmit Packet1
Start Timer
Packet should arrive
ACK should be sent
ACK would normally
Arrive at this time
Receive Packet 1
Send AXK 1
Time Expires
Receive ACK 1
Cancel Timer
Packet Lost
Timer
Timer
IP
• IP : Internet Protocol
– UDP : User Datagram Protocol
• RTP, traceroute
– TCP : Transmission Control Protocol
• HTTP, FTP, ssh
OSI Model TCP/IP Hierarchy Protocols
7th
Application Layer
6th
Presentation Layer
5th
Session Layer
4th
Transport Layer
3rd
Network Layer
2nd
Link Layer
1st
Physical Layer
Application Layer
Transport Layer
Network Layer
Link Layer
Link Layer : includes device driver and network interface card
Network Layer : handles the movement of packets, i.e. Routing
Transport Layer : provides a reliable flow of data between two hosts
Application Layer : handles the details of the particular application
IP
• Responsible for end to end transmission
• Sends data in individual packets
• Maximum size of packet is determined
by the networks
– Fragmented if too large
• Unreliable
– Packets might be lost, corrupted,
duplicated, delivered out of order
IP addresses
• 4 bytes
– e.g. 163.1.125.98
– Each device normally gets one (or more)
– In theory there are about 4 billion available
• But…
Routing
• How does a device know where to send
a packet?
– All devices need to know what IP
addresses are on directly attached
networks
– If the destination is on a local network,
send it directly there
Routing (cont)
• If the destination address isn’t local
– Most non-router devices just send
everything to a single local router
– Routers need to know which network
corresponds to each possible IP address
Allocation of addresses
• Controlled centrally by ICANN
– Fairly strict rules on further delegation to
avoid wastage
• Have to demonstrate actual need for them
• Organizations that got in early have
bigger allocations than they really need
IP packets
• Source and destination addresses
• Protocol number
– 1 = ICMP, 6 = TCP, 17 = UDP
• Various options
– e.g. to control fragmentation
• Time to live (TTL)
– Prevent routing loops
IP Datagram
Vers Len TOS Total Length
Identification Flags Fragment Offset
TTL Protocol Header Checksum
Source Internet Address
Destination Internet Address
Options... Padding
Data...
0 4 8 16 19 24 31
Field Purpose
Vers IP version number
Len Length of IP header (4 octet units)
TOS Type of Service
T. Length Length of entire datagram (octets)
Ident. IP datagram ID (for frag/reassembly)
Flags Don’t/More fragments
Frag Off Fragment Offset
Field Purpose
TTL Time To Live - Max # of hops
Protocol Higher level protocol (1=ICMP,
6=TCP, 17=UDP)
Checksum Checksum for the IP header
Source IA Originator’s Internet Address
Dest. IA Final Destination Internet Address
Options Source route, time stamp, etc.
Data... Higher level protocol data
We only looked at the IP addresses, TTL and protocol #
IP Routing
• Routing Table
Destination IP address
IP address of a next-hop router
Flags
Network interface specification
Application
Transport
Network
Link
Application
Transport
Network
Link
Network
Link
Source Destination
Router
UDP
• Thin layer on top of IP
• Adds packet length + checksum
– Guard against corrupted packets
• Also source and destination ports
– Ports are used to associate a packet with a
specific application at each end
• Still unreliable:
– Duplication, loss, out-of-orderness possible
User Datagram Protocol)
UDP datagram
Destination PortSource Port
Application data
0 16 31
ChecksumLength
Field Purpose
Source Port 16-bit port number identifying originating application
Destination Port 16-bit port number identifying destination application
Length Length of UDP datagram (UDP header + data)
Checksum Checksum of IP pseudo header, UDP header, and data
Typical applications of UDP
– Where packet loss etc is better handled by
the application than the network stack
– Where the overhead of setting up a
connection isn’t wanted
• VOIP
• NFS – Network File System
• Most games
IPv6
• 128 bit addresses
– Make it feasible to be very wasteful with
address allocations
• Lots of other new features
– Built-in autoconfiguration, security options,
…
• Not really in production use yet
Network Standard
Network
Architecture
Network Protocol
ISO
OSI
TCP/IP
WIFI/WIMAX Protocols
ITU-T
HTTP
Data Communication 1

More Related Content

What's hot

Data communication
Data communicationData communication
Data communicationAnne Perera
 
Networking devices
Networking devicesNetworking devices
Networking devicesrupinderj
 
wired and wireless networks
wired and wireless networkswired and wireless networks
wired and wireless networksKavitha Ravi
 
History of wireless communication
History of wireless communicationHistory of wireless communication
History of wireless communicationAJAL A J
 
Data Communication & Computer Networks : Serial and parellel transmission
Data Communication & Computer Networks : Serial and parellel transmissionData Communication & Computer Networks : Serial and parellel transmission
Data Communication & Computer Networks : Serial and parellel transmissionDr Rajiv Srivastava
 
Transmission media (data communication)
Transmission media (data communication)Transmission media (data communication)
Transmission media (data communication)Pritom Chaki
 
Presentation on data communication
Presentation on data communicationPresentation on data communication
Presentation on data communicationHarpreet Dhaliwal
 
10.data transmission
10.data transmission10.data transmission
10.data transmissionDeepak Sharma
 
Powerpoint for data communication
Powerpoint for data communication Powerpoint for data communication
Powerpoint for data communication samanthaanderson21
 
Modulation techniques
Modulation techniquesModulation techniques
Modulation techniquesSathish Kumar
 
switching techniques in data communication and networking
switching techniques in data communication and networkingswitching techniques in data communication and networking
switching techniques in data communication and networkingHarshita Yadav
 
Data communications
Data communicationsData communications
Data communicationsAshwini
 
Wan technologies
Wan technologiesWan technologies
Wan technologiesOnline
 
Frequency modulation
Frequency modulationFrequency modulation
Frequency modulationAkanksha_Seth
 

What's hot (20)

Data communication
Data communicationData communication
Data communication
 
Switching systems lecture1
Switching  systems lecture1Switching  systems lecture1
Switching systems lecture1
 
Networking devices
Networking devicesNetworking devices
Networking devices
 
wired and wireless networks
wired and wireless networkswired and wireless networks
wired and wireless networks
 
History of wireless communication
History of wireless communicationHistory of wireless communication
History of wireless communication
 
Data Communication & Computer Networks : Serial and parellel transmission
Data Communication & Computer Networks : Serial and parellel transmissionData Communication & Computer Networks : Serial and parellel transmission
Data Communication & Computer Networks : Serial and parellel transmission
 
Transmission media (data communication)
Transmission media (data communication)Transmission media (data communication)
Transmission media (data communication)
 
Data transmission
Data transmissionData transmission
Data transmission
 
Presentation on data communication
Presentation on data communicationPresentation on data communication
Presentation on data communication
 
Multiplexing : FDM
Multiplexing : FDMMultiplexing : FDM
Multiplexing : FDM
 
10.data transmission
10.data transmission10.data transmission
10.data transmission
 
Powerpoint for data communication
Powerpoint for data communication Powerpoint for data communication
Powerpoint for data communication
 
Telephone networks
Telephone networksTelephone networks
Telephone networks
 
Modulation techniques
Modulation techniquesModulation techniques
Modulation techniques
 
switching techniques in data communication and networking
switching techniques in data communication and networkingswitching techniques in data communication and networking
switching techniques in data communication and networking
 
Data communications
Data communicationsData communications
Data communications
 
Wan technologies
Wan technologiesWan technologies
Wan technologies
 
Presentation on CDMA
Presentation on CDMAPresentation on CDMA
Presentation on CDMA
 
Circuit Switching
Circuit SwitchingCircuit Switching
Circuit Switching
 
Frequency modulation
Frequency modulationFrequency modulation
Frequency modulation
 

Viewers also liked

Digital Communication 1
Digital Communication 1Digital Communication 1
Digital Communication 1admercano101
 
Chapter 1: Introduction to Data Communication and Networks
Chapter 1: Introduction to Data Communication and NetworksChapter 1: Introduction to Data Communication and Networks
Chapter 1: Introduction to Data Communication and NetworksShafaan Khaliq Bhatti
 
Data communication by Phone Lines
Data communication by Phone LinesData communication by Phone Lines
Data communication by Phone LinesMuhammad Ahtsham
 
Analytic geometry lecture2
Analytic geometry lecture2Analytic geometry lecture2
Analytic geometry lecture2admercano101
 
Analytic geometry lecture1
Analytic geometry lecture1Analytic geometry lecture1
Analytic geometry lecture1admercano101
 
Data communication - Lecture-01
Data communication - Lecture-01 Data communication - Lecture-01
Data communication - Lecture-01 Sehrish Rafiq
 
Data communications Class notes
Data communications  Class notesData communications  Class notes
Data communications Class notesDr.YNM
 
Data communication (simple explanation)
Data communication (simple explanation)Data communication (simple explanation)
Data communication (simple explanation)Twist Akid Sultan
 
Data communication and network Chapter -1
Data communication and network Chapter -1Data communication and network Chapter -1
Data communication and network Chapter -1Zafar Ayub
 
Introduction of reflection
Introduction of reflection Introduction of reflection
Introduction of reflection Ravindra Rathore
 
Ch11 communication
Ch11  communicationCh11  communication
Ch11 communicationadrienne0901
 
Lecture 5 phasor notations
Lecture 5 phasor notationsLecture 5 phasor notations
Lecture 5 phasor notationsRavindra Rathore
 

Viewers also liked (20)

Limits
LimitsLimits
Limits
 
Digital Communication 1
Digital Communication 1Digital Communication 1
Digital Communication 1
 
Chapter 1: Introduction to Data Communication and Networks
Chapter 1: Introduction to Data Communication and NetworksChapter 1: Introduction to Data Communication and Networks
Chapter 1: Introduction to Data Communication and Networks
 
Trigonometry101
Trigonometry101Trigonometry101
Trigonometry101
 
Data communication by Phone Lines
Data communication by Phone LinesData communication by Phone Lines
Data communication by Phone Lines
 
Analytic geometry lecture2
Analytic geometry lecture2Analytic geometry lecture2
Analytic geometry lecture2
 
Analytic geometry lecture1
Analytic geometry lecture1Analytic geometry lecture1
Analytic geometry lecture1
 
Data communication - Lecture-01
Data communication - Lecture-01 Data communication - Lecture-01
Data communication - Lecture-01
 
Data communications Class notes
Data communications  Class notesData communications  Class notes
Data communications Class notes
 
Data communication (simple explanation)
Data communication (simple explanation)Data communication (simple explanation)
Data communication (simple explanation)
 
Data communication and network Chapter -1
Data communication and network Chapter -1Data communication and network Chapter -1
Data communication and network Chapter -1
 
Lecture-2 Data Communication ~www.fida.com.bd
Lecture-2 Data Communication ~www.fida.com.bdLecture-2 Data Communication ~www.fida.com.bd
Lecture-2 Data Communication ~www.fida.com.bd
 
Sistem Komunikasi Digital
Sistem Komunikasi DigitalSistem Komunikasi Digital
Sistem Komunikasi Digital
 
26 io -ii file handling
26  io -ii  file handling26  io -ii  file handling
26 io -ii file handling
 
Introduction of reflection
Introduction of reflection Introduction of reflection
Introduction of reflection
 
Ch11 communication
Ch11  communicationCh11  communication
Ch11 communication
 
28 networking
28  networking28  networking
28 networking
 
21 multi threading - iii
21 multi threading - iii21 multi threading - iii
21 multi threading - iii
 
22 multi threading iv
22 multi threading iv22 multi threading iv
22 multi threading iv
 
Lecture 5 phasor notations
Lecture 5 phasor notationsLecture 5 phasor notations
Lecture 5 phasor notations
 

Similar to Data Communication 1

Chapter 4 data communication fundamental
Chapter 4   data communication fundamentalChapter 4   data communication fundamental
Chapter 4 data communication fundamentalN. A. Sutisna
 
Skr+3200+chapter+1+(kweh)
Skr+3200+chapter+1+(kweh)Skr+3200+chapter+1+(kweh)
Skr+3200+chapter+1+(kweh)Ammar Shafiq
 
Networking_and_Data_communication.pptx
Networking_and_Data_communication.pptxNetworking_and_Data_communication.pptx
Networking_and_Data_communication.pptxUniversity of Lucknow
 
Lecture handouts-Data Communication.pdf
Lecture handouts-Data Communication.pdfLecture handouts-Data Communication.pdf
Lecture handouts-Data Communication.pdfSnehanshuShekhar5
 
is chap5.pptx
is chap5.pptxis chap5.pptx
is chap5.pptxTeshome48
 
Entrepreneurship & Commerce in IT - 09 - The internet and the world wide web
Entrepreneurship & Commerce in IT - 09 - The internet and the world wide webEntrepreneurship & Commerce in IT - 09 - The internet and the world wide web
Entrepreneurship & Commerce in IT - 09 - The internet and the world wide webSachintha Gunasena
 
Unit - 1.pptx
Unit - 1.pptxUnit - 1.pptx
Unit - 1.pptxKavinD11
 
ITP-22 -COMPUTER NETWORK.pptx
ITP-22 -COMPUTER NETWORK.pptxITP-22 -COMPUTER NETWORK.pptx
ITP-22 -COMPUTER NETWORK.pptxMohammadAsim91
 
Unit1_COMPUTER_COMMUNICATIONSSlides.pptx
Unit1_COMPUTER_COMMUNICATIONSSlides.pptxUnit1_COMPUTER_COMMUNICATIONSSlides.pptx
Unit1_COMPUTER_COMMUNICATIONSSlides.pptxNANDIKHATHARANIKUMAR1
 
Unit 1 introduction to computer networks
Unit 1  introduction to computer networksUnit 1  introduction to computer networks
Unit 1 introduction to computer networkspavan kumar Thatikonda
 
chapter1.ppt
chapter1.pptchapter1.ppt
chapter1.pptExamIUB
 
Networking Basic Refresh.pdf
Networking Basic Refresh.pdfNetworking Basic Refresh.pdf
Networking Basic Refresh.pdfCS Knowledge
 
Network fundamental
Network fundamentalNetwork fundamental
Network fundamentalsravya reddy
 
Computer networks
Computer networksComputer networks
Computer networksTej Kiran
 
chapter1.ppt
chapter1.pptchapter1.ppt
chapter1.pptExamIUB
 
chapter1.ppt
chapter1.pptchapter1.ppt
chapter1.pptExamIUB
 

Similar to Data Communication 1 (20)

Chapter 4 data communication fundamental
Chapter 4   data communication fundamentalChapter 4   data communication fundamental
Chapter 4 data communication fundamental
 
Skr+3200+chapter+1+(kweh)
Skr+3200+chapter+1+(kweh)Skr+3200+chapter+1+(kweh)
Skr+3200+chapter+1+(kweh)
 
Welcome to epix
Welcome to epixWelcome to epix
Welcome to epix
 
Networking_and_Data_communication.pptx
Networking_and_Data_communication.pptxNetworking_and_Data_communication.pptx
Networking_and_Data_communication.pptx
 
Lecture handouts-Data Communication.pdf
Lecture handouts-Data Communication.pdfLecture handouts-Data Communication.pdf
Lecture handouts-Data Communication.pdf
 
is chap5.pptx
is chap5.pptxis chap5.pptx
is chap5.pptx
 
Entrepreneurship & Commerce in IT - 09 - The internet and the world wide web
Entrepreneurship & Commerce in IT - 09 - The internet and the world wide webEntrepreneurship & Commerce in IT - 09 - The internet and the world wide web
Entrepreneurship & Commerce in IT - 09 - The internet and the world wide web
 
Unit - 1.pptx
Unit - 1.pptxUnit - 1.pptx
Unit - 1.pptx
 
ITP-22 -COMPUTER NETWORK.pptx
ITP-22 -COMPUTER NETWORK.pptxITP-22 -COMPUTER NETWORK.pptx
ITP-22 -COMPUTER NETWORK.pptx
 
Unit1_COMPUTER_COMMUNICATIONSSlides.pptx
Unit1_COMPUTER_COMMUNICATIONSSlides.pptxUnit1_COMPUTER_COMMUNICATIONSSlides.pptx
Unit1_COMPUTER_COMMUNICATIONSSlides.pptx
 
Unit 1 introduction to computer networks
Unit 1  introduction to computer networksUnit 1  introduction to computer networks
Unit 1 introduction to computer networks
 
Data Communication.ppt
Data Communication.pptData Communication.ppt
Data Communication.ppt
 
Data Communication.ppt
Data Communication.pptData Communication.ppt
Data Communication.ppt
 
chapter1.ppt
chapter1.pptchapter1.ppt
chapter1.ppt
 
Networking Basic Refresh.pdf
Networking Basic Refresh.pdfNetworking Basic Refresh.pdf
Networking Basic Refresh.pdf
 
Computer networking
Computer networkingComputer networking
Computer networking
 
Network fundamental
Network fundamentalNetwork fundamental
Network fundamental
 
Computer networks
Computer networksComputer networks
Computer networks
 
chapter1.ppt
chapter1.pptchapter1.ppt
chapter1.ppt
 
chapter1.ppt
chapter1.pptchapter1.ppt
chapter1.ppt
 

Recently uploaded

Work Experience for psp3 portfolio sasha
Work Experience for psp3 portfolio sashaWork Experience for psp3 portfolio sasha
Work Experience for psp3 portfolio sashasashalaycock03
 
Ultra structure and life cycle of Plasmodium.pptx
Ultra structure and life cycle of Plasmodium.pptxUltra structure and life cycle of Plasmodium.pptx
Ultra structure and life cycle of Plasmodium.pptxDr. Asif Anas
 
Unveiling the Intricacies of Leishmania donovani: Structure, Life Cycle, Path...
Unveiling the Intricacies of Leishmania donovani: Structure, Life Cycle, Path...Unveiling the Intricacies of Leishmania donovani: Structure, Life Cycle, Path...
Unveiling the Intricacies of Leishmania donovani: Structure, Life Cycle, Path...Dr. Asif Anas
 
The Stolen Bacillus by Herbert George Wells
The Stolen Bacillus by Herbert George WellsThe Stolen Bacillus by Herbert George Wells
The Stolen Bacillus by Herbert George WellsEugene Lysak
 
P4C x ELT = P4ELT: Its Theoretical Background (Kanazawa, 2024 March).pdf
P4C x ELT = P4ELT: Its Theoretical Background (Kanazawa, 2024 March).pdfP4C x ELT = P4ELT: Its Theoretical Background (Kanazawa, 2024 March).pdf
P4C x ELT = P4ELT: Its Theoretical Background (Kanazawa, 2024 March).pdfYu Kanazawa / Osaka University
 
Over the counter (OTC)- Sale, rational use.pptx
Over the counter (OTC)- Sale, rational use.pptxOver the counter (OTC)- Sale, rational use.pptx
Over the counter (OTC)- Sale, rational use.pptxraviapr7
 
Clinical Pharmacy Introduction to Clinical Pharmacy, Concept of clinical pptx
Clinical Pharmacy  Introduction to Clinical Pharmacy, Concept of clinical pptxClinical Pharmacy  Introduction to Clinical Pharmacy, Concept of clinical pptx
Clinical Pharmacy Introduction to Clinical Pharmacy, Concept of clinical pptxraviapr7
 
5 charts on South Africa as a source country for international student recrui...
5 charts on South Africa as a source country for international student recrui...5 charts on South Africa as a source country for international student recrui...
5 charts on South Africa as a source country for international student recrui...CaraSkikne1
 
CapTechU Doctoral Presentation -March 2024 slides.pptx
CapTechU Doctoral Presentation -March 2024 slides.pptxCapTechU Doctoral Presentation -March 2024 slides.pptx
CapTechU Doctoral Presentation -March 2024 slides.pptxCapitolTechU
 
How to Show Error_Warning Messages in Odoo 17
How to Show Error_Warning Messages in Odoo 17How to Show Error_Warning Messages in Odoo 17
How to Show Error_Warning Messages in Odoo 17Celine George
 
Riddhi Kevadiya. WILLIAM SHAKESPEARE....
Riddhi Kevadiya. WILLIAM SHAKESPEARE....Riddhi Kevadiya. WILLIAM SHAKESPEARE....
Riddhi Kevadiya. WILLIAM SHAKESPEARE....Riddhi Kevadiya
 
Education and training program in the hospital APR.pptx
Education and training program in the hospital APR.pptxEducation and training program in the hospital APR.pptx
Education and training program in the hospital APR.pptxraviapr7
 
Easter in the USA presentation by Chloe.
Easter in the USA presentation by Chloe.Easter in the USA presentation by Chloe.
Easter in the USA presentation by Chloe.EnglishCEIPdeSigeiro
 
AUDIENCE THEORY -- FANDOM -- JENKINS.pptx
AUDIENCE THEORY -- FANDOM -- JENKINS.pptxAUDIENCE THEORY -- FANDOM -- JENKINS.pptx
AUDIENCE THEORY -- FANDOM -- JENKINS.pptxiammrhaywood
 
How to Manage Cross-Selling in Odoo 17 Sales
How to Manage Cross-Selling in Odoo 17 SalesHow to Manage Cross-Selling in Odoo 17 Sales
How to Manage Cross-Selling in Odoo 17 SalesCeline George
 
In - Vivo and In - Vitro Correlation.pptx
In - Vivo and In - Vitro Correlation.pptxIn - Vivo and In - Vitro Correlation.pptx
In - Vivo and In - Vitro Correlation.pptxAditiChauhan701637
 
Prescribed medication order and communication skills.pptx
Prescribed medication order and communication skills.pptxPrescribed medication order and communication skills.pptx
Prescribed medication order and communication skills.pptxraviapr7
 
Protein Structure - threading Protein modelling pptx
Protein Structure - threading Protein modelling pptxProtein Structure - threading Protein modelling pptx
Protein Structure - threading Protein modelling pptxvidhisharma994099
 

Recently uploaded (20)

Work Experience for psp3 portfolio sasha
Work Experience for psp3 portfolio sashaWork Experience for psp3 portfolio sasha
Work Experience for psp3 portfolio sasha
 
Ultra structure and life cycle of Plasmodium.pptx
Ultra structure and life cycle of Plasmodium.pptxUltra structure and life cycle of Plasmodium.pptx
Ultra structure and life cycle of Plasmodium.pptx
 
Unveiling the Intricacies of Leishmania donovani: Structure, Life Cycle, Path...
Unveiling the Intricacies of Leishmania donovani: Structure, Life Cycle, Path...Unveiling the Intricacies of Leishmania donovani: Structure, Life Cycle, Path...
Unveiling the Intricacies of Leishmania donovani: Structure, Life Cycle, Path...
 
The Stolen Bacillus by Herbert George Wells
The Stolen Bacillus by Herbert George WellsThe Stolen Bacillus by Herbert George Wells
The Stolen Bacillus by Herbert George Wells
 
P4C x ELT = P4ELT: Its Theoretical Background (Kanazawa, 2024 March).pdf
P4C x ELT = P4ELT: Its Theoretical Background (Kanazawa, 2024 March).pdfP4C x ELT = P4ELT: Its Theoretical Background (Kanazawa, 2024 March).pdf
P4C x ELT = P4ELT: Its Theoretical Background (Kanazawa, 2024 March).pdf
 
Over the counter (OTC)- Sale, rational use.pptx
Over the counter (OTC)- Sale, rational use.pptxOver the counter (OTC)- Sale, rational use.pptx
Over the counter (OTC)- Sale, rational use.pptx
 
March 2024 Directors Meeting, Division of Student Affairs and Academic Support
March 2024 Directors Meeting, Division of Student Affairs and Academic SupportMarch 2024 Directors Meeting, Division of Student Affairs and Academic Support
March 2024 Directors Meeting, Division of Student Affairs and Academic Support
 
Clinical Pharmacy Introduction to Clinical Pharmacy, Concept of clinical pptx
Clinical Pharmacy  Introduction to Clinical Pharmacy, Concept of clinical pptxClinical Pharmacy  Introduction to Clinical Pharmacy, Concept of clinical pptx
Clinical Pharmacy Introduction to Clinical Pharmacy, Concept of clinical pptx
 
5 charts on South Africa as a source country for international student recrui...
5 charts on South Africa as a source country for international student recrui...5 charts on South Africa as a source country for international student recrui...
5 charts on South Africa as a source country for international student recrui...
 
CapTechU Doctoral Presentation -March 2024 slides.pptx
CapTechU Doctoral Presentation -March 2024 slides.pptxCapTechU Doctoral Presentation -March 2024 slides.pptx
CapTechU Doctoral Presentation -March 2024 slides.pptx
 
How to Show Error_Warning Messages in Odoo 17
How to Show Error_Warning Messages in Odoo 17How to Show Error_Warning Messages in Odoo 17
How to Show Error_Warning Messages in Odoo 17
 
Riddhi Kevadiya. WILLIAM SHAKESPEARE....
Riddhi Kevadiya. WILLIAM SHAKESPEARE....Riddhi Kevadiya. WILLIAM SHAKESPEARE....
Riddhi Kevadiya. WILLIAM SHAKESPEARE....
 
Education and training program in the hospital APR.pptx
Education and training program in the hospital APR.pptxEducation and training program in the hospital APR.pptx
Education and training program in the hospital APR.pptx
 
Easter in the USA presentation by Chloe.
Easter in the USA presentation by Chloe.Easter in the USA presentation by Chloe.
Easter in the USA presentation by Chloe.
 
Personal Resilience in Project Management 2 - TV Edit 1a.pdf
Personal Resilience in Project Management 2 - TV Edit 1a.pdfPersonal Resilience in Project Management 2 - TV Edit 1a.pdf
Personal Resilience in Project Management 2 - TV Edit 1a.pdf
 
AUDIENCE THEORY -- FANDOM -- JENKINS.pptx
AUDIENCE THEORY -- FANDOM -- JENKINS.pptxAUDIENCE THEORY -- FANDOM -- JENKINS.pptx
AUDIENCE THEORY -- FANDOM -- JENKINS.pptx
 
How to Manage Cross-Selling in Odoo 17 Sales
How to Manage Cross-Selling in Odoo 17 SalesHow to Manage Cross-Selling in Odoo 17 Sales
How to Manage Cross-Selling in Odoo 17 Sales
 
In - Vivo and In - Vitro Correlation.pptx
In - Vivo and In - Vitro Correlation.pptxIn - Vivo and In - Vitro Correlation.pptx
In - Vivo and In - Vitro Correlation.pptx
 
Prescribed medication order and communication skills.pptx
Prescribed medication order and communication skills.pptxPrescribed medication order and communication skills.pptx
Prescribed medication order and communication skills.pptx
 
Protein Structure - threading Protein modelling pptx
Protein Structure - threading Protein modelling pptxProtein Structure - threading Protein modelling pptx
Protein Structure - threading Protein modelling pptx
 

Data Communication 1

  • 1. ECE 512L Data Communication Engr. Adriano Mercedes H. Cano Jr. Electronics Engineering College of Engineering Education University of Mindanao - Tagum College
  • 2. Course Outline • Module 1: Data Communications Fundamentals – Communication model, – Data communication network – Standards, – Protocol – OSI model, – TCP/IP,
  • 3. Course Outline • Module 2: Fundamental Concepts of Data Communications – Data Communications Circuits – Data Communications Codes – Bar Codes – Line Control Unit – Error Control – Error Detection – Error Correction – Serial Interfaces – Data Communications Modems – ITU-T Modem Recommendations – Character Synchronization
  • 4. Course Outline • Module 3: Data Link Control Protocols – Data-Link Protocol Functions – Character- and Bit-Oriented Data-Link – Protocols – Asynchronous Data-Link Protocols – Asynchronous Transfer Mode – Synchronous Data-Link Protocols – High-Level Data-Link Control – Public Switched Data Networks – CCITT X.25 User-to-Network Interface Protocol – Integrated Services Digital Network – Synchronous Data-Link Control
  • 5. Course Outline • Module 4: Data Communication Networking – Introduction to Switched Circuits – Circuit Switching and Packet Switching – Local Area Networks, Applications, and Architectures • Ethernet • Ring • Token Ring • FDDI – Local Area Networks and Interconnections • Repeaters • Bridges and Switches • Routers and Gateways – The Internet • Overview of the Internet • The Internet Protocol • Domain Name Systems • Internet Protocol Over Internet
  • 6. Reference Books • Advance Electronics Communication – Wayne Tomasi • Data Communications and Networking – Behrouz A. Forouzan
  • 8. Introduction • Data generally are defined as information that has been processed, organized, and is stored in digital form • Information is defined as knowledge or intelligence. • Data communications is the process of transferring digital information (usually in binary form) between two or more points.
  • 9. Data Communication Standards Error detection and correction Network Devices Header & Trailer Encryption Location A Location B
  • 10. Introduction • Data Transmission • is the transmission, reception, and processing of digital information • Transmission is either parallel or serial
  • 11. Introduction • Transmission Modes – Simplex (SX) mode, data transmission is unidirectional; receive-only, transmit-only, or one-way-only lines. • Ex. Commercial radio broadcasting – Half-duplex (HDX) mode, data transmission is possible in both directions but not at the same time. Also called two-way-alternate or either-way lines. • Ex. Citizens band (CB) radio – Full duplex (FDX) mode, transmissions are possible in both directions simultaneously, but they must be between the same two stations. also called two-way simultaneous, duplex, or both-way lines. • Ex. A local telephone – Full/full duplex (F/FDX) mode, transmission is possible in both directions at the same time but not between the same two stations (i.e., one station is transmitting to a second station and receiving from a third station at the same time). • Full/full duplex is possible only on multipoint circuits. • Ex. postal system
  • 13. • Data can be propagated to the network by either – Segment – packet – frame, Introduction
  • 14. • Data communications networks – are systems of interrelated computers and computer equipment(called nodes) and connected together through the public telephone network.(media links) – Its purpose is to transfer digital information from one place to another. Introduction
  • 16. History of Data Communication • 1753. One of the earliest means of communicating electrically coded information through a 26 wire system. • 1833. Carl Friedrich Gauss developed a system based on a 5x5 matrix representing 25 letters. • 1832. The telegraph (the first data communication system) was invented by Samuel F.B. Morse. • 1840. The American patent for the telegraph was granted. • 1844. The first telegraph line was established between Baltimore and Washington D.C. conveying the first telegraph message “What hath God wrought!” 16
  • 17. • 1849. The first slow-speed telegraph printer was invented. • 1850. Western Union Telegraph Company was formed in Rochester, New York, for the purpose of carrying coded messages from person to another. • 1860. “High-speed” printers (15 bps) became available. • 1874. Emile Baudot invented the a telegraph multiplexer that allowed signals from up to six different telegraph machines to be transmitted simultaneously over a single wire. • 1875. The telephone was invented by Alexander Graham Bell. 17 History of Data Communication
  • 18. History of Data Communication • 1899. Guglielmo Marconi succeeded in sending radio (wireless) telegraph messages. • 1920. The first commercial radio stations carrying voice information were installed. • 1930s. Konrad Zuis, a German engineer, demonstated a computing machine. • 1940. Bell Laboratories developed the first special purpose computer using electromechanical relays for performing logical operations. • 1946. The first modern-day computer (ENIAC) was developed by J. Presper Eckert and John Mauchley at the University of Pennsylvania. 18
  • 19. History of Data Communication • 1949. The U.S. National Bureau of Standards developed the first all-electronic diode based computed capable of executing stored-programs. • 1950s. “Batch processing” computers used punched cards as an input interface, printers as an output interface, and magnetic tape reels for data storage. The first general purpose computer in the form of an automatic sequence-controlled calculator was developed jointly by Harvard University and IBM Corporation. • 1951. Remington Rand Corporation built the first mass-produced electronic computer (UNIVAC). 19
  • 20. History of Data Communication • 1960s. Batch-processing systems were replaced by on-line processing systems with terminals connected directly to the computer through serial or parallel communication lines. • 1968. The landmark US Supreme Court Carterfone decision allowed non-Bell (non AT&T) equipment to be connected to the vast AT&T network. • 1969. The internet began to evolve at the Advanced Research Projects Agency (ARPA) through the ARPANET. • 1970s. Microprocessor-controlled microcomputers were developed. 20
  • 21. History of Datacom • 1980s. Personal computers became an essential item in the home and the workplace. Since then, the need to exchange digital information, and consequently, the need for data communication circuits, networks, and systems increased exponentially. • 1983. AT&T agreed in a court settlement to divest itself of operating companies that provide basic local telephone service to various geographic regions of the US as a result of an anti-trust suit filed by the federal government. 21
  • 22. History of Data Communication • Mid 1980s to 1995. The United Stated National Science Foundation (NSF) funded a high-speed backbone called the NSFNET. • 1989. Tim Berners-Lee and Robert Cailliau build the prototype system which became the World Wide Web at CERN. • 1991. Anders Olsson transmits solitary waves through an optical fiber with a data rate of 32 billion bits per second. • 1992. Neil Papworth sends the first SMS Internet2 organization is created. • 1994. Internet radio broadcasting is born. 22
  • 23. History of Data Communication • 1999. 45% of Australians have a mobile phone. Sirius satellite radio is introduced. • 2001. First digital cinema transmission by satellite in Europe of a feature film by Bernard Pauchon and Philippe Binant is undertaken. • 2003. Apple launches the iTunes Music Store and sells one million songs in its first week. MySpace is launched. • 2004. What would become the largest social networking site in the world, Facebook is launched. • 2005. YouTube, the video sharing site is launched. . 23
  • 24. History of Data Communication • 2006. Twitter, microblogging is introduced. 24
  • 25. Network Architecture Network Architecture Design of communication network is a set of layers and protocols outline the products and services is a framework for the specification
  • 26. • General classifications: – Current: include the most modern and sophisticated networks and protocols available. – Legacy: no one really wants to use it, but for some reason it just will not go away. – Legendary: Old and No longer in use Network Architecture
  • 27. • can be classified in two different ways: – Broadcast : • messages are intended for all subscribers on the network • all stations and devices on the network share a single communication channel – Point to point: • All transmissions from one station are intended for and received by the other station. – multicasting: • when messages are intended for a specific group of subscribers. Network Architecture
  • 29. Network Architecture electrical specifications hardware arrangements software procedures Transmission media layers of functional responsibility Company A A Company YA Company BA Company X A Protocol
  • 30. Network Protocols sets of rules that allows two hardware or software processes to work together how much data can be sent? how it will be sent? how much data can be sent? how it will be addressed? what procedure will be used to ensure that there are no undetected errors?
  • 31. Network Protocols • Protocol stack – The list of protocols used by a system, which generally includes only one protocol per layer
  • 32. Layered Network Architecture Consist of two or more independent levels. Each level has a specific set of responsibilities and functions data transfer, flow control, data segmentation reassembly, sequence control, error detection and correction, notification Reduce Complexity Standardizes interfaces Facilitates modular engineering Ensure Interoperable engineering Accelerates evolution simplifies teaching and learning
  • 33. Connection- oriented protocol 1. Establishes handshake before any data are actually transmitted between two stations. 2. Require s acknowledgement of the data as they are being transmitted. (ensure reliability) 3. Provide some means of error control 4. When a connection is no longer needed, a specific handshake drops the connection. Network Protocols Connections are sometimes referred to as sessions, virtual circuits, or logical connections. Connectionless protocol 1. Send data with a source and destination address without a handshake . 2. Do not support error control or acknowledgment procedures, making them 3. Data being transmitted usually do not have extra overhead
  • 36. • Syntax – refers to the structure or format of the data within the message, which includes the sequence in which the data are sent. • Ex: the first byte of a message might be the address of the source and the second byte the address of the destination. • Semantics – refers to the meaning of each section of data. • Ex: does a destination address identify only the location of the final destination, or does it also identify the route the data takes between the sending and receiving locations? Network Protocols
  • 37. Copyright 2005 John Wiley & Sons, Inc 1 - 37 Data Comm. Standards • Standard – is an object or procedure considered by an authority or by general consent as a basis of comparison • Data communications standards are not laws, however—they are simply suggested ways of implementing procedures and accomplishing results • Guidelines that have been generally accepted by the data communications industry
  • 38. Copyright 2005 John Wiley & Sons, Inc 1 - 38 Data Comm. Standards • Importance – Compatibility of hardware and/or software systems among different companies – Help promote competition and decrease the price • Types of Standards – Formal standards • Developed by an industry or government standards-making body – De-facto standards • Emerge in the marketplace and widely used • Lack official backing by a standards-making body
  • 39. Copyright 2005 John Wiley & Sons, Inc 1 - 39 Standardization Processes • Specification – Developing the nomenclature and identifying the problems to be addressed • Identification of choices – Identifying solutions to the problems and choose the “optimum” solution • Acceptance – Defining the solution, getting it recognized by industry so that a uniform solution is accepted
  • 40. Copyright 2005 John Wiley & Sons, Inc 1 - 40 Some Data Comm. Standards Layer Common Standards 5. Application layer HTTP, HTML (Web) MPEG, H.323 (audio/video) IMAP, POP (e-mail) 4. Transport layer TCP (Internet) SPX (Novell LANs) 3. Network layer IP (Internet) IPX (Novell LANs) 2. Data link layer Ethernet (LAN) Frame Relay (WAN) PPP (dial-up via modem for MAN) 1. Physical layer RS-232c cable (LAN) Category 5 twisted pair (LAN) V.92 (56 kbps modem)
  • 41. Copyright 2005 John Wiley & Sons, Inc 1 - 41 Major Standards Bodies • ISO (International Organization for Standardization) – Technical recommendations for data communication interfaces – Composed of each country’s national standards orgs. – Based in Geneva, Switzerland (www.iso.ch) • ITU-T (International Telecommunications Union – Telecom Group – Technical recommendations about telephone, telegraph and data communications interfaces – Composed of representatives from each country in UN – Based in Geneva, Switzerland (www.itu.int)
  • 42. Copyright 2005 John Wiley & Sons, Inc 1 - 42 • ANSI (American National Standards Institute) – Coordinating organization for US (not a standards- making body) – www.ansi.org • IEEE (Institute of Electrical and Electronic Engineers) – Professional society; also develops mostly LAN standards – standards.ieee.org • IETF (Internet Engineering Task Force) – Develops Internet standards – No official membership (anyone welcomes) – www.ietf.org Major Standards Bodies
  • 44. Standards • Proprietary – are generally manufactured and controlled by one company. – Ex: Apple Macintosh. – Advantages • are tighter control, easier consensus, and a monopoly. – Disadvantages • include lack of choice for the customers, higher financial investment, overpricing, and reduced customer protection against the manufacturer going out of business.
  • 45. Standards • Open System – any company can produce compatible equipment or software; however, often a royalty must be paid to the original company. – Ex: IBM’s personal computer. – Advantages • customer have a choice, compatibility between venders, and competition by smaller companies. – Disadvantages • less product control and increased difficulty acquiring agreement • between vendors for changes or updates. • In addition, standard items are not always as • compatible as we would like them to be.
  • 46. STANDARDS ORGANIZATIONS • A consortium of organizations, governments, manufacturers, and users meet on a regular basis to ensure an orderly flow of information within data communications networks and systems by establishing guidelines and standards. • The intent is that all data communications equipment manufacturers and users comply with these standards. • Standards organizations generate, control, and administer standards. • Often, competing companies will form a joint committee to create a compromised standard that is acceptable to everyone.
  • 47. • Each layer adds value to services provided by sets of lower layers. • The highest level is offered the full set of services needed to run a distributed data application. • Each layer is essentially independent of every other layer. • Advantages – facilitates peer-to-peer communications protocols • where a given layer in one system can logically communicate with its corresponding layer in another system. • allows different computers to communicate at different levels. • Disadvantage – tremendous amount of overhead required Layered network architecture
  • 48. In case of more >1 destination: service access point (SAP) address is used to define which entity the service is intended.
  • 49. Protocol Data Unit • communications between two corresponding layers requires PDU. • can be a header added at the beginning of a message or a trailer appended to the end of a message. • As data passes from one layer into another, headers and trailers are added and removed from the PDU. • The process of adding or removing PDU information is called encapsulation /decapsulation
  • 52. OPEN SYSTEMS INTERCONNECTION • In 1983, the ISO and ITU-T (CCITT) adopted a seven-layer communications architecture reference model. • The primary purpose is to serve as a structural guideline for exchanging information between computers, workstations, and networks. • Each layer consists of specific protocols for communicating.
  • 53. OPEN SYSTEMS INTERCONNECTION • was developed to facilitate the intercommunications of data processing equipment by separating network responsibilities into seven distinct layers. • As with any layered architecture, overhead information is added to a PDU in the form of headers and trailers. • In fact, if all seven levels of the OSI model are addressed, as little as 15% of the transmitted message is actually source information, and the rest is overhead.
  • 55. Please Do Not Touch Steve’s Pet Alligator
  • 56. Open Systems Interconnection  User networking applications and interfacing to the network  Encoding language used in transmission  Job management tracking  Data tracking as it moves through a network  Network addressing and packet transmission on the network  Frame formatting for transmitting data across a physical communications link  Transmission method used to propagate bits through a network 56 LAYERS FUNCTIONS
  • 58. OSI and its Protocol Data Units ECE @Saint Louis University, Baguio City 58
  • 65. • Layered network • architectures consist of two or more independent levels Application layer
  • 70. TCP/IP • Transmission Control Protocol/Internet protocol • TCP at the transport layer and IP at the network layer • Designed by Vinton G. Cerf and Robert E. Kahn • developed by the United States Defense Advanced Research Projects Agency (DARPAor ARPA)
  • 71. TCP • Reliable, full-duplex, connection-oriented, stream delivery – Interface presented to the application doesn’t require data in individual packets – Data is guaranteed to arrive, and in the correct order without duplications • Or the connection will be dropped – Imposes significant overheads
  • 72. Applications of TCP • Most things! – HTTP, FTP, … • Saves the application a lot of work, so used unless there’s a good reason not to
  • 73. TCP implementation • Connections are established using a three-way handshake • Data is divided up into packets by the operating system • Packets are numbered, and received packets are acknowledged • Connections are explicitly closed – (or may abnormally terminate)
  • 74. TCP Packets • Source + destination ports • Sequence number (used to order packets) • Acknowledgement number (used to verify packets are received)
  • 75. TCP Segment Destination Port Acknowledgment Number Options... Padding Data... 0 4 10 16 19 24 31 Source Port WindowLen Sequence Number Reserved Flags Urgent PointerChecksum Field Purpose Source Port Identifies originating application Destination Port Identifies destination application Sequence Number Sequence number of first octet in the segment Acknowledgment # Sequence number of the next expected octet (if ACK flag set) Len Length of TCP header in 4 octet units Flags TCP flags: SYN, FIN, RST, PSH, ACK, URG Window Number of octets from ACK that sender will accept Checksum Checksum of IP pseudo-header + TCP header + data Urgent Pointer Pointer to end of “urgent data” Options Special TCP options such as MSS and Window Scale You just need to know port numbers, seq and ack are added
  • 76. TCP : Data transfer HostClient Send Packet 1 Start Timer Retransmit Packet1 Start Timer Packet should arrive ACK should be sent ACK would normally Arrive at this time Receive Packet 1 Send AXK 1 Time Expires Receive ACK 1 Cancel Timer Packet Lost Timer Timer
  • 77. IP • IP : Internet Protocol – UDP : User Datagram Protocol • RTP, traceroute – TCP : Transmission Control Protocol • HTTP, FTP, ssh
  • 78. OSI Model TCP/IP Hierarchy Protocols 7th Application Layer 6th Presentation Layer 5th Session Layer 4th Transport Layer 3rd Network Layer 2nd Link Layer 1st Physical Layer Application Layer Transport Layer Network Layer Link Layer Link Layer : includes device driver and network interface card Network Layer : handles the movement of packets, i.e. Routing Transport Layer : provides a reliable flow of data between two hosts Application Layer : handles the details of the particular application
  • 79. IP • Responsible for end to end transmission • Sends data in individual packets • Maximum size of packet is determined by the networks – Fragmented if too large • Unreliable – Packets might be lost, corrupted, duplicated, delivered out of order
  • 80. IP addresses • 4 bytes – e.g. 163.1.125.98 – Each device normally gets one (or more) – In theory there are about 4 billion available • But…
  • 81. Routing • How does a device know where to send a packet? – All devices need to know what IP addresses are on directly attached networks – If the destination is on a local network, send it directly there
  • 82. Routing (cont) • If the destination address isn’t local – Most non-router devices just send everything to a single local router – Routers need to know which network corresponds to each possible IP address
  • 83. Allocation of addresses • Controlled centrally by ICANN – Fairly strict rules on further delegation to avoid wastage • Have to demonstrate actual need for them • Organizations that got in early have bigger allocations than they really need
  • 84. IP packets • Source and destination addresses • Protocol number – 1 = ICMP, 6 = TCP, 17 = UDP • Various options – e.g. to control fragmentation • Time to live (TTL) – Prevent routing loops
  • 85. IP Datagram Vers Len TOS Total Length Identification Flags Fragment Offset TTL Protocol Header Checksum Source Internet Address Destination Internet Address Options... Padding Data... 0 4 8 16 19 24 31 Field Purpose Vers IP version number Len Length of IP header (4 octet units) TOS Type of Service T. Length Length of entire datagram (octets) Ident. IP datagram ID (for frag/reassembly) Flags Don’t/More fragments Frag Off Fragment Offset Field Purpose TTL Time To Live - Max # of hops Protocol Higher level protocol (1=ICMP, 6=TCP, 17=UDP) Checksum Checksum for the IP header Source IA Originator’s Internet Address Dest. IA Final Destination Internet Address Options Source route, time stamp, etc. Data... Higher level protocol data We only looked at the IP addresses, TTL and protocol #
  • 86. IP Routing • Routing Table Destination IP address IP address of a next-hop router Flags Network interface specification Application Transport Network Link Application Transport Network Link Network Link Source Destination Router
  • 87. UDP • Thin layer on top of IP • Adds packet length + checksum – Guard against corrupted packets • Also source and destination ports – Ports are used to associate a packet with a specific application at each end • Still unreliable: – Duplication, loss, out-of-orderness possible User Datagram Protocol)
  • 88. UDP datagram Destination PortSource Port Application data 0 16 31 ChecksumLength Field Purpose Source Port 16-bit port number identifying originating application Destination Port 16-bit port number identifying destination application Length Length of UDP datagram (UDP header + data) Checksum Checksum of IP pseudo header, UDP header, and data
  • 89. Typical applications of UDP – Where packet loss etc is better handled by the application than the network stack – Where the overhead of setting up a connection isn’t wanted • VOIP • NFS – Network File System • Most games
  • 90. IPv6 • 128 bit addresses – Make it feasible to be very wasteful with address allocations • Lots of other new features – Built-in autoconfiguration, security options, … • Not really in production use yet