Networking 3

Hello ka blogger.. this is our 3rd meeting in IT-2 Network Management/principles with Prof. John Mark Dose

i hope u will enjoy while you reading..

IP Addressing

IP Address Classes

Classless Inter-Domain Routing (CIDR)

•          Basically the method that ISPs (Internet Service Providers) use to allocate an amount of addresses to a company, a home

•          Ex : 192.168.10.32/28

•          The slash notation (/) means how many bits are turned on (1s)

CIDR Values

Subnetting

q  Subnetting is logically dividing the network by extending the 1’s used in SNM

q  Advantage

q  Can divide network in smaller parts

q  Restrict Broadcast traffic

q  Security

q  Simplified Administration

q  Classful IP Addressing SNM are a set of 255’s and 0’s.

q  In Binary it’s contiguous 1’s and 0’s.

q  SNM cannot be any value as it won’t follow the rule of contiguous 1’s and 0’s.

q  Possible subnet mask values

q  0

q  128

q  192

q  224

q  240

q  248

q  252

q  254

q  255

Formula

q  Number of subnets – 2^x-2

Where X = number of bits borrowed

q  Number of Hosts – 2^y-2

Where y = number of 0’s

q  Block Size = Total number of Address

Block Size = 256-Mask

Addressing Without Subnets

Subnet Mask

8-Bit Subnet
Mask Also written as “/24,” where 24 represents the number of 1s in the mask

Networking 2

Bandwidth

It is like number of  lanes on a highway

Switch

Many Collision domain

One broadcast domain

Bridge

One collision domain

One broadcast domain

Hub

One collision domain

One broadcast domain

OSI Model

  To address the problem of networks increasing in size and in number, the International Organization for Standardization (ISO) researched many network schemes and recognized that there was a need to create a network model.

v  This would help network builders implement networks that could communicate and work together.

ISO - International Organization for Standardization

OSI - Open System Interconnection

IOS - Internetwork Operating System

The OSI Reference Model

7. Application - This layer deals with networking applications.

Examples:

v  Email

v  Web browsers

PDU - User Data

6.  Presentation - This layer is responsible for presenting the data in the required format which may include:

v  Code Formatting

v  Encryption

v  Compression

PDU - Formatted Data

5.  Session

v  This layer establishes, manages, and terminates sessions between two communicating hosts.

v  Creates Virtual Circuit

v  Coordinates communication between systems

v  Organize their communication by offering three different modes

v  Simplex

v  Half Duplex

v  Full Duplex

   Example:

§  Client Software

o   ( Used for logging in)

   PDU - Formatted Data

4.  Transport

v  This layer breaks up the data from the sending host and then reassembles it in the receiver.

v  It also is used to insure reliable data transport across the network.

v  Can be reliable or unreliable

v  Sequencing

v  Acknowledgment

v  Retransmission

v  Flow Control

   PDU - Segments

3.  Network

v  This layer breaks up the data from the sending host and then reassembles it in the receiver.

v  It also is used to insure reliable data transport across the network.

v  Can be reliable or unreliable

v  Sequencing

v  Acknowledgment

v  Retransmission

v  Flow Control

       PDU – Segments

2.  Data Link

v  Sometimes referred to as the “Cisco Layer”.

v  End to End Delivery

v  Provide logical addressing that routers use for path determination

v  Segments are encapsulated

v  Internetwork Communication

v  Packet forwarding

v  Packet Filtering

v  Makes “Best Path Determination”

v  Fragmentation

   PDU – Packets – IP/IPX

1.  Physical

v  Sometimes referred to as the “Cisco Layer”.

v  End to End Delivery

v  Provide logical addressing that routers use for path determination

v  Segments are encapsulated

v  Internetwork Communication

v  Packet forwarding

v  Packet Filtering

v  Makes “Best Path Determination”

v  Fragmentation

   PDU – Packets – IP/IPX

Networking 1

Hello ka blogger.. this is our first meeting in IT-2 Network Management/principles with Prof. John Mark Dosejo.
i hope you enjoy while you reading...

Our first meeting is all about Networking-which means communicating through device.


ICONS:

• ATM Switch
• Router
• Switch
• Com Server
• ISDN Switch
• Bridge
• PC
• Laptop
• Phones
• File Server
• Hub
• Modem
• Phone Customer
• Network Cloud
• Building
• Home Office

Data Networks - sharing data through the use of floppy disks is not an efficient or cost-effective manner.

Businesses needed a solution that would successfully address the following three problem.

• How to avoid duplication of equipment and resources.
• How to communicate efficiently.
• How to set up and manage a network.

 Two Classification of Devices:

• End User Device - includes computer, printer, scanner, and other device that provide services directly to the user.
• Network User Device - network device include all the device that connect the end user divices together to allow them to communicate.

Network Interface Card

- a network interface card (NIC) is a printed  circuit board that provide network communication capabilities to and from a personal Computer. Also called LAN Adapter.

HUB

 - Connect's a group of husts

 - It depends the maximum

 - Up link multiple hub

 - Hub is never manageble

Switches - Add more intelligence to data trasfer management.

Network Topology

- defines the structure of the network

- One part of the topology defination is the physical topology. which is the actual layout of the wire or media.

BUS TOPOLOGY 

- Used a single backbone cable that is terminated at both ends.

- All the hosts connect directly to his backbone.

RING TOPOLOGY

- Connect one host to the next and the last host to the first.

- This creates a phisical ring of cable.

STAR TOPOLOGY 

- Connects all cable to a central point of concentration.

EXTENDED STAR TOPOLOGY 

- An link individuals star together by connecting the hubs and/or switches. this topology can extend the scope and coverage of the network.

MESH TOPOLOGY

- Is implemented to provide as much protection as possible from interruption of service.

- Each host has its own connects to all other hosts.

- Although the Internet has multiple paths to any one location, it does not adopt the full mesh topology.