CERT-IN: Indian Computer Emergence Response Team

PROJECTON

COMPUTER NETWORK DESGINING

In Fulfillment of Six weeks Industrial Training at

CERT-IN, ELECTRONICS NIKETAN

Presented by : Project Guide: Dheeraj .

KIIT College of Engg. .

PROJECT OVERVIEW :• Computer Network Designing means better planning,

creation with minimal complexity . It involves determining the network structure.

• The concept of creating the network is to set up the communication link between user from one place to another.

• This project mainly cover the basics of computer network and also determine how data is running over network. The aim of this project is to provide all the possible communication link .

Why Network

Designing

…….?

Network DesigningNetwork design means mostly capacity planning having enough bandwidth to

keep data moving.

NOTE: **Effective designing sometimes lead to result in over engineering **

Define Network Design Objectives :some uses of the network will need a lot of bandwidth (multimedia), we may also need to address:• Security • Possible wireless connectivity• Reliability and/or availability

– Like speed for a car, how much are you willing to afford?

Designing Phases

• Designing a network is typically broken into three sections:– Determine requirements– Define the overall

architecture– Choose technology and

specific devices

TYPES OF NETWORK• Local area Network (LAN)

This is one of the original categories of network, and one of the simplest. LAN networks connect computers together over relatively small distances, such as within a single building or within a small group of buildings.

TYPES OF NETWORK• Wide Area Network (WAN)

WAN networks connect computers together over large physical distances, remotely connecting them over one huge network and allowing them to communicate even when far apart. The Internet is a WAN, and connects computers all around the world together.

Metropolitan Area Network (MAN)

This is a network which is larger than a LAN but smaller than a WAN, and incorporates elements of both. It typically spans a town or city and is owned by a single person or company, such as a local council or a large company.

PROJECTMODULES

Virtual Private Network (VPN)

A virtual LAN (VLAN) is any broadcast domain that is partitioned in a computer network at the data link layer (OSI layer 2).

VLANs allow network administrators to group hosts together even if the hosts are not on the same network switch. This can greatly simplify network design and deployment.

VTP is a layer 2 protocol that allows to control, create, and delete VLANs from a central VTP server.Cisco switches are in “VTP server mode” by default.Three VTP modes:• SERVER MODE : all VLAN information such as VLAN number and VLAN

name is stored locally on a separate NVRAM.• CLIENT MODE: a switch will accept and store in its RAM all VLAN

information received from the VTP Server.It behaves like a VTP Server, but you are unable to create, modify or delete VLAN’s on it.

• TRANSPARENT MODE: The VTP Transparent mode is something between a VTP Server and a VTP Client but does not participate in the VTP Domain.

VLAN TRUNKING PROTOCOL (VTP)

VLAN TRUNKING PROTOCOL (VTP)

SPANNING TREE PROTOCOL(STP)To avoid unwanted Switching Loops, there are some mechanisms. One of the most common names of these mechanisms is STP (Spanning Tree Protocol).STP Example on Packet Tracer :

SPANNING TREE PROTOCOL(STP)Four states of an STP port :

- Blocking (20 seconds)- Listening (15 second)- Learning (15 second)- ForwardingOn Switch0: On Switch1:

On Switch2: On Switch3:

The STP blocks one of the port of Switch3. This election is done according to the cost to the root. The Designated Ports are selected and the remaining Non-Designated Port on a segment is blocked.