BASIC NETWORKING

NETWORKING

WHAT IS A NETWORK?

Consist of two or more computer that are linked in order to share resources, exchange files or allow electronic communications.

LINKED THRU:

Cables

Telephone lines

Radio waves

Satellites

Infrared light beams

BASIC TYPES OF NETWORKS:

LAN

MAN

WAN

LAN – Local Area Network

Confined to a relatively small area or limited to a geographic area

MAN – Metropolitan Area Network

Covers larger geographic area such as cities or schools

WAN –Wide Area Network

Connect larger geographic areas such as world

Dedicated Transoceanic Cabling or satellite-used to connect the network

OSI MODEL

OSI Model

APPLICATION SET

LAYER 7 PRESENTATION-layer that actually interacts with the

operating system or application whenever the user chooses to transfer files, read messages, or perform other network-related activities

OSI Model

APPLICATION SET

LAYER 6 PRESENTATION-takes the data provided by the

application layer and converts it into standard format that the other layers can understand

OSI Model

APPLICATION SET

LAYER 5 SESSION-establishes, maintains and ends

communication with the receiving device

Recap: of OSI Model

APPLICATION SET

LAYER 4 TRANSPORT-maintains flow control of data and

provides for error checking and recovery of data between the devices

Recap: of OSI Model

APPLICATION SET

LAYER 3 NETWORK-the way that the data will be sent to recipient device is determined .

Logical protocols, routing and addressing are handled here.

OSI Model

APPLICATION SET

LAYER 2 DATA-the appropriate physical protocol is

assigned to the data

OSI Model

APPLICATION SET

LAYER 1 PHYSICAL-the actual hardware. The physical

characteristic of the network such as connections , voltage level and timing

NETWORK TOPOLOG

Y

WHAT IS A TOPOLOGY

Two types of topology:

Physical Refers to the layout of cables,

computer and other peripherals

Logical Method used to pass the

information between the computers

TYPES OF PHYSICAL TOPOLOGIES

Bus

Hub/Star

Ring

Bus Topology

Consists of main run of cable with a terminator at each end.

All nodes are connected to the linear cable.

STAR Topology

Designed with each node connected directly to a central network hub or concentrator.

RING Topology

Computers are connected on a single circle of cable

No terminated ends

UNSHIELDED TWISTED PAIR

PRIMARY LAN MEDIA CONDUCTED

Unshielded Twisted Pair Shielded Twisted Pair Coaxial Cable Fiber Optic

WIRELESS Microwave Radio Broadcast Radio Spread Spectrum Radio Infrared Light

UTP CABLE

Is the most certainly by far the most popular network cable around the world.

UTP CATEGORIES

Category 1, 2, 3, 4, 5, 6, 7-a specification for the type of

copper wire and jacks.

-refers to the revision of the specification and in practical terms refers to the number of twists inside the wire

Category 1

-typically a telephone wire

-not capable of supporting computer network traffic and is not twisted.

Category 2-7

-network wire specifications

-can support computer network and telephone traffic

CATEGORY

DATA RATE

USAGE

1 1 Mbps Traditional telephone and ISDN-Modem

2 4 Mbps Token Ring

3 10 Mbps Token Ring and 10BASE-T

4 16 Mbps Token Ring

5 100 Mbps 10 Mbps Ethernet, 1000 Mbps Fast Ethernet and Token Ring

5e 1000 Mbps Gigabit Ethernet

6 – 7 1000 Mbps Gigabit Ethernet

WIRING THE UTP CABLES

2 POPULAR WIRING SCHEMES

T-568A Supposed to be the standard for new

installation

T-568B An acceptable alternative

MODULAR PLUG

Rj-45 -standard connector used in utp cables except category 1

-8 conductor cables with 8 pins

Rj-11 -modular plug used in category 1

-used in telephone wire

T-568APIN WIRE COLOR

1 WHITE GREEN

2 GREEN

3 WHITE ORANGE

4 BLUE

5 WHITE BLUE

6 ORANGE

7 WHITE BROWN

8 BROWN

T-568B

PIN WIRE COLOR FUNCTION PAIR

1 WHITE ORANGE TRANSMITTED DATA + 2

2 ORANGE TRANSMITTED DATA - 2

3 WHITE GREEN RECEIVED DATA + 3

4 BLUE PAIR 1 1

5 WHITE BLUE PAIR 1 1

6 GREEN RECEIVED DATA - 3

7 WHITE BROWN 4

8 BROWN 4

2 TYPES OF CABLE FOR 10/100BASE-T

STRAIGHT THRU CABLE Used in peer-to-peer networking Used in connecting from PC to Hub Used in connecting two hubs with an

uplink port

CROSS-OVER CABLE Used in connecting PC to PC networking Used to connect two hubs in the absence

of uplink port

STRAIGHT THRU CABLE

Both end of the cable uses the same wiring schemes either:

T568 A <<<<->>>> T568A

T568B <<<<->>>> T568B

CROSS-OVER CABLE

end of the cable has dissimilar wiring schemes

T568 B <<<<->>>> T568A or vice-versa

ETHERNET CABLE SUMMARY

SPECIFICATION CABLE TYPE MAXIMUM LENGTH

10BaseT Unshielded Twisted Pair

100 meters

10Base2 Thin Coaxial 185 meters

10Base5 Thick Coaxial 500 meters

10BaseF Fiber Optic 2000 meters

100BaseT UTP 100 meters

100BaseTX UTP 220 meters

TOOLS AND MATERIALS:

UTP Cable Cat5

Crimper

Cable Tester

Wire stripper

Modular Plug –RJ45

CRIMPER

is a tool designed to crimp or connect a connector to the end of a cable. For example, network cables and phone cables are created using a crimping tool to connect the RJ-45and RJ-11 connectors to the end of the cable

NETWORK CABLE TESTER

is an electronic device used to verify the electrical connections in a cable or other wired assembly

Wire Stripper

simple manual wire stripper is a pair of opposing blades much like scissors or wire cutters

NETWORKING DEVICES

NETWORKING DEVICES

NIC

HUBS

SWITCHES

ROUTER

MODEM

NIC – Network Interface Card

Required to a PC to make them ready for network use

FACTORS TO CONSIDER: Speed of your hub, switch –Ethernet or fast

Ethernet Type of connection you need –Rj-45 for

twisted or BNC for coaxial

Bus Architecture

HUB

Sometimes used to refer to any piece of network equipment that connects PC’s together but actually serve as repeater.

Use to extend a network

SWITCH

Reduces the amount of the unnecessary traffic

Divide the network into smaller, less congested sections

Routers

checks the data packet for its destination address and protocol format details

forward data packets across computer networks

Modems

(modulator-demodulator) is a device that modulates an analog carrier signal to encode digital information, and also demodulates such a carrier signal to decode the transmitted information.

The goal is to produce a signal that can be transmitted easily and decoded to reproduce the original digital data

TYPES OF LAN

2 MAJOR TYPES OF LAN

PEER-TO-PEER

CLIENT/SERVER

PEER-TO-PEER

Network set up that allow users to share resources and files located on their computer and to access shared resources found on other computer.

All computer are considered equal

No dedicated server needed

ADVANTAGES:

Less Initial expense Easy to set up

DISADVANTAGES: Decentralized Unsecured

CLIENT/SERVER

Network set up that allow the network to centralize functions and applications in one or more dedicated file server.

ADVANTAGES

Centralized Resources and data security are controlled through a

server

Scalability Any or all elements can be replaced individually as

need increaser

Flexibility New technology can be easily integrated into the

system

Interoperability All components work together

Accessibility Server can be accessed remotely and across multiple

platforms

DISADVANTAGES

Expense Requires initial investment in dedicated

server

Maintenance Large networks will require a staff to

ensure efficient operation

Dependence When server goes down, operation will

cease across the network

NETWORK OPERATING SYSTEM

Coordinates the activities of multiple computers across a network.

Acts as a director to keep the network running smoothly

Examples of NOS

Appleshare

LANtastic

Microsoft Windows NT Server

Microsoft Windows for Workgroup

Novell Netware

APPLESHARE

Apple Computer’s networking solution.

Includes both server and workstation software

LANtastic

Powerful, inexpensive program with good interface for DOS and Windows

Best security for industries

MICROSOFT WINDOWS FOR WORKGROUP Peer to peer networking version of

windows

Allows client only workstation and server only workstations

MICROSOFT WINDOWS NT SERVER An enhanced version of Windows NT

that provides a powerful client/server network operating system.

Contains all of the features of Windows NT including capabilities as an application server and multitasking.

Novell Netware

Most popular client/server operating program available on the market

Has a file by file compression which allows system to hold more online data by compressing files that are frequently accessed or used.

COMMON PROTOCOLS

Ethernet Local Talk Token Ring FDDI ATM

ETHERNET

By far the most widely used

CSMA/CD (Carrier Sense Multiple Access/Collision

Detection) – access method used by the ethernet

FAST ETHERNET

Requires the use of different, more expensive network concentrators/hubs and network interface cards.

GIGABIT ETHERNET

Primarily used for backbones on a network

Transmission speed is 1Gbps

Used fiber optic cabling and copper

LOCALTALK

Network protocol that was developed by Apple Computer, Inc. for Mac computers.

Uses CSMA/CA (CSMA with collision Avoidance)

FDDI

Fiber Distributed Data Interface

Used primarily to interconnected two or more local area networks often large distances

Access method used is token ring.

ATM

Asynchronous Transfer Mode

Network protocol that transmits data at a speed of 155 Mbps and higher.

IP ADDRESS

Internet Protocol

Is a unique identifying number of a machine and normally expressed in decimal format as a dotted number.

Four groups of numbers separated by dots and each group is called octets.

NETWORK CLASSESS

CLASS TYPE

NETWORK RANGE DEFAULT SUBNET MASK

Class A 1.0.0.0 to 127.255.255.255

255.0.0.0

Class B 128.0.0.0 to 191.255.255.255

255.255.0.0

Class C 192.0.0.0 to 223.255.255.255

255.255.255.0

Class D 224.0.0.0 to 239.255.255.255

n/a

Class E 240.0.0.0 to 255.255.255.255

n/a

PRIVATE CLASS IP ADDRESSES

Class Private Start Address

Private End Address

A 10.0.0.0 10.255.255.255

B 172.16.0.0 172.31.255.255

C 192.168.0.0 192.168.255.255

-RESERVED FOR MULTICAST-MAINLY USED ON RESEARCH-SHOULD NOT BE USED BY ORDINARY NODES ON THE INTERNET

CLASS D & E

IP ADDRESSING NOTATION

IPv4 Consist of four bytes (32 bits) known as

octets. Uses dotted decimal for human readability

purposes

Ex. 00001010 00000000 00000000 00000001

Written as: 10.0.0.1

IP ADDRESSING NOTATION

IPv6 Consist of 16 bytes (128 bits) long rather

than four bytes (32 bits). Pairs are separated by a colon and each

bytes in turns is represented as a pair of hexadecimal numbers

Ex. E3D7:0000:0000:0000:51F4:9BC8:COA8:6420

LOOP BACK IP ADDRESS

127.0.0.1 is the loop back IP Address A test mechanism of network adapters Use test the behavior of network

interface

ZERO ADDRESS

Unable to communicate properly on the internet

Benefits of Network Addressing:

Can improve security (by isolating critical nodes) and can reduce network traffic (by preventing transmissions between nodes that do not need to communicate with each other).

IP ADDRESS ASIGNMENT

STATIC IP ADDRESS Does not change over time unless changed

manually Remain the same consistently Manually assigned by the network administrator

DYNAMIC IP ADDRESS Keeps on changing Used when having a consistent IP address is not

necessary Assigned by the ISP Automatically obtained from the network

IP SECTIONING