Computer Architecture

Depending on the
complexity of a network, it can be organized in different ways, called
“Architectures”


so, Network Architectures are simply arrangement & layout of networks

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

1

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

2

PEER-TO PEER NETWORK

CLIENT/SERVER NETWORK

NETWORK TOPOLOGY

 A topology is a way of “laying out” the network now a

days we do consider them as network architecture

STAR TOPOLOGY

7

 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

A Star network is
more complex,
with all the users
connected
together.
It needs a router but no server

BUS TOPOLOGY

9

 Pros:

 Little cabling

 Easy to install

 Cons:

 Difficult to modify

 Difficult to isolate

fault

 Break in the bus cable

stops all transmission

RING TOPOLOGY

10

 Pros:

 Easy to install

 Easy to identify fault

 Cons:

 Delay in large ring

 Break in the ring stops all

transmission

A ring network is
extremely simple.
The user computers
are connected into a
ring and take turns
exchanging
information.
They
need special
software but no
servers or routers

More complex
networks need
servers and at least one router to function.
Something has to
manage the process of sharing data and
access

- Wide Area Network (WAN) - A “network of

networks”. Good for connecting the network
in a corporate HQ to the network of a sales
office elsewhere in the state.

- Local Area Network (LAN)- Connects the

computers of users in the same organization/
same building or campus.

Larger Network Architectures

- A Virtual Private Network (VPN) acts like a LAN

and can send confidential data over public
network safely. It is cheaper and more
convenient than a WAN/LAN combination, but
not any faster.

VPNs - The Network That Isn’t “Real”

INTRANET, INTERNET &EXTRANET

Always design your
network to be a
simple as possible, but consider all the needs of the users, including growth for the future.