Transcript Tollbooths & Highways

Introduction to
Networking
CCNA 1, Module 1
By
Steven Beckwith
Aims
 By the end of this chapter you should be
able to:
 Understand the fundamentals of Internet Connectivity
 Describe the basic components of a PC’s Hardware and
Software
 Demonstrate TCP/IP Configuration and testing
 Diferentiate between High Speed and Dialup Connectivity
 Understand and demonstrate Decimal, Binary and
Hexadecimal conversion and Boolean Logic
 Show a basic understanding of IP Addresses and Subnet
Masks
Internet Fundamentals
 The Internet
 A network of Interconnected Networks
 Computers can exist without the Internet but the Internet
cannot exist without computers
 The Internet can be thought of as a Tree
The trunk and branches are the pathways connecting networks
The leaves are the computers
Internet Connectivity
 Computers connect to the internet in a
number of ways, can you list them?
 Dial-up (Modem)
 ISDN
 DSL
 Cable
 Network
PC Basics (Components)
 Electronic components
 Transistor
 Integrated Circuit (IC)
 Resistor
 Capacitor
 Connector
 Light Emitting Diode (LED)
PC Basics (Components)
 PC components
 Printed Circuit Board (PCB)
 CD-ROM drive
 Central Processing Unit (CPU)
 Floppy Disk Drive
 Hard Disk Drive
 Microprocessor
 Motherboard
 Random Access Memory (RAM)
PC Basics (Components) Contd.
 PC components
 Read Only Memory (ROM)
 Bus
 Expansion Slots
 System Unit
 Power Supply
PC Motherboard Components
 Backplane
 Memory Chip
 Network Interface
Card (NIC)
 Video Card
 Sound Card
 Parallel Port
 Serial Port
 Mouse Port




Mouse Port
Keyboard Port
Power Cord
Universal Serial Bus
(USB) Port
Desktop Vs Laptop
 Desktop
 Comes in two styles
Desktop
Tower
Used in the home and at work
 Not suitable for mobile use
 Connects directly to network via NIC
 Can connect to network via a modem

Desktop Vs Laptop
 Laptop
 Comes in a variety of styles
Laptop
Palmtop
Compact
Gives flexibility to mobile users
 Connects directly to network via NIC
 Can connect to network via modem and Cellular Telephone

Selecting a NIC
 Points to consider
 Type of network
Ethernet
Token Ring
FDDI

Type of Medium
Twisted pair
Coaxial
Fiber
Wireless
Selecting a NIC (Contd).
 Points to consider
 Type of System bus
 ISA
 PCI
 USB
 PCMCIA
High Speed and Dialup
Year
Speed
(bits/sec)
Application
1960’s
300
Connecting Dumb terminals to
Mainframe computer
1970’s
300
Bulletin boards introduced
1980’s
4600
Transferring files and graphics
1990s
28800
Widening use of the internet
1998
56000
More graphic based web pages
and file transfers
2000s
2,000,000
Introduction of broadband for
home users
TCP/IP
 A set of Protocols to allow computers on
different networks to communicate
 Used to access the Internet
 PC Requires:
 An IP Address
 Subnet Mask
 Default Gateway
 This information is obtained from the
network administrator
TCP/IP Configuration
TCP/IP Testing
Ping
 A protocol used to test TCP/IP Connectivity
 Stands for Packet Internet Groper
 Sends multiple IP packets to destination computer
(typically 4 -packets)
 Will receive the same number of replies
 Information obtained will allow you to ascertain network
connectivity
IPConfig
 Used to verify current IP configuration
 Lab 1.1.6
Ping
 Procedures for verifying connectivity
 Ping 127.0.0.1 – Internel loopback address
 Ping IP Address of host computer – Verifies own configuration
 Ping default gateway IP address – verifies router can be accessed
 Ping remote IP address – verifies connectivity to remote host
Tracert
 Traces the route traffic takes from source to
destination
 Lab 1.1.7
Decimal Notation
 All Number systems consist of symbols and
rules for using them
 We use the Decimal number system
 Consists of the symbols 0,1,2,3,4,5,6,7,8,9.
Binary Notation
 Computers use Binary notation
 Information is stored in memory as a 1
(on) 0r 0 (off)
 Has only 2 symbols 0 and 1
 Called Binary digITS
 Usually represented in groups of 8 BITS
 8 BITS = 1 Byte or Octet
 1024 bytes = 1 Kilobyte (Kb)
 1024 Kb = 1 Megabyte (Mb)
 1024 Mb = 1 Gigabyte (Gb)
Binary Notation
 Possible combinations of 1s and 0s in 8 bits
= 0 -255
Hexadecimal Notation
 Computers represent large numbers as
Hexadecimal
 Has 16 symbols, numbers 0-9 and A, B,C, D, E, F
representing 10 – 15.
Number Conversions
 Lab 1.2.5 Decimal to Binary Conversion
 Lab 1.2.6 Binary to Decimal Conversion
 Lab 1.2.8 Hexadecimal Conversions
Boolean Logic
 Boolean logic is based on digital
circuitry that accepts one or two
incoming voltages.
 Based on the input voltages, output
voltage is generated.
 For the purpose of computers the
voltage difference is associated as two
states, on or off.
 These two states are in turn associated
as a 1 or a 0, which are the two digits in
the binary numbering system.
Logic Gates
 NOT
 The NOT operation takes whatever value is presented, 0 or 1, and
inverts it.
 A one becomes a zero and a zero becomes a one.
Logic Gates
 AND
 The AND operation takes two input values.
 If both are 1, the logic gate generates a 1 output.
 Otherwise it outputs a 0.
Logic Gates
 OR
 The OR operation also takes two input values.
 If at least one of the input values is 1, the output value is 1
IP Addressing
 An IP Address is a 32 bit address represented in Decimal
notation for ease of reading
 eg. 192.168.10.143
 Has 2 parts
 Network portion
 Host Portion
 Has a Subnet Mask
 255.0.0.0
 255.255.0.0
 255.255.255.0
Subnet Masks
 Subnet Mask is used to identify the network
portion if the address
 Converting the IP address 10.34.23.134 to binary would result in:
00001010.00100010.00010111.10000110



Performing a Boolean AND of the IP address 10.34.23.134 and the
subnet mask 255.0.0.0 produces the network address of this host:
00001010.00100010.00010111.10000110
11111111.00000000.00000000.00000000
00001010.00000000.00000000.00000000
Network Address = 10.0.0.0
Subnet Masks
 Performing a Boolean AND of the IP
address 10.34.23.134 and the subnet
mask 255.255.0.0 produces the network
address of this host:
 Answer
00001010.00100010.00010111.10000110
11111111.11111111.00000000.00000000
00001010.00100010.00000000.00000000

Network Address = 10.34.0.0
Good luck in the test!