COMPUTER NETWORKS

Prepared by S.Sabari Giri Murugan Faculty G2-Grade KL University

SESSION IITypes of Network Architecture- Peer-to-Peer & Client/Server, Workgroup Vs. Domain. Network Topologies, Types of Topologies, Logical and physical topologies, selecting the Right Topology

TYPES OF NETWORK ARCHITECTURE

Session 2

TYPES OF NETWORKS - PEER-TO-PEER Good for small

environments, usually up to 10 computers

No dedicated network administrator

Each computer must have specific permissions assigned

Sharing resources can become a problem if the computer with the resource is down

Security is a serious issue

3

TYPES OF NETWORKS - CLIENT/SERVER A server has a special

Network Operating system (NOS) to help provide resources to multiple users

Client/Server environments usually have one or more network administrators

Problems can include access, security, and integrity of data

Backups are needed in this environment

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PEER-TO PEER NETWORK (CONT..)

CLIENT/SERVER NETWORKING (CONT..)

NETWORK TOPOLOGY A topology is a way of “laying out” the

network. Topologies can be either physical or logical.

Physical topologies describe how the cables are run.

Logical topologies describe how the network messages travel

TOPOLOGY Topology: physical or logical arrangement of

devices

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FULLY CONNECTED MESH TOPOLOGY

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FULLY CONNECTED MESH TOPOLOGY

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Pros: Dedicated links Robustness Privacy Easy to identify

fault Cons:

A lot of cabling I/O ports Difficult to move

STAR TOPOLOGY

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Pros: One I/O port per device Little cabling Easy to install Robustness Easy to identify fault

Cons: Single point of failure More cabling still

required

Hub

BUS TOPOLOGY

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BUS TOPOLOGY

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Pros: Little cabling Easy to install

Cons: Difficult to modify Difficult to isolate

fault Break in the bus

cable stops all transmission

RING TOPOLOGY

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RING TOPOLOGY

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Pros: Easy to install Easy to identify fault

Cons: Delay in large ring Break in the ring stops

all transmission

PROS & CONS

Topology Advantages Disadvantages

Bus Cheap. Easy to install. Difficult to reconfigure.Break in bus disablesentire network.

Star Cheap. Easy to install.Easy to reconfigure.Fault tolerant.

More expensive than bus.

Ring Efficient. Easy to install. Reconfiguration difficult.Very expensive.

Mesh Simplest. Most fault tolerant. Reconfiguration extremely difficult. Extremely expensive.Very complex.

NETWORKING MODELS Two networking models:

Workgroup Domain

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WORKGROUP VS. DOMAIN

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Workgroup Peer-to-Peer

Environment Effective for small

environments Security is a problem

Domain Client/Server

Environment Effective for larger

environments Network

administrator has control

WORKGROUP MODEL All computers are equal Also known as peer-to-peer Each computer maintains own set of

Resources Accounts Security information

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WORKGROUP MODEL (CONTINUED)

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DOMAIN MODEL Centralizes all shared resources Single point of administrative and security control Simpler to manage from administrative and security

standpoint Requires at least one domain controller (DC)

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DOMAIN MODEL (CONTINUED)

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INTRANET, INTERNET &EXTRANET