Definition of network architecture:

• Network architecture is the way network are designed to communicate

Type of network architecture:

      1. Peer-to-peer architecture

• Definition - A network model in which all computers can function as clients or servers as needed and there's no centralized control over the network resources.
• Most computers functions as clients or servers.
• Example: A computer can act as a server by sharing a printer it's connected to and at the same time act as client by accessing a file shared by another computer on the network.

Advantages of peer-to-peer network:

• Less startup cost to setup the network architecture-no need for a server
• Easy to install and configure for the computers in the network.
• When a peer fails it will not affect the other peers so the network is reliable.

Disadvantages of peer-to-peer network:

• Decentralized - No central repository for files and applications
• Less security - Does not provide the security available on a client/server network.
• Every user is taking care his/her own machine.

     2. Client-server network

• Definition - Network in which one or more computers act as a server and the other computers (clients) on the networks request services from the server.

Client-server

• Computers connected together to create a network which fall into two categories : clients and server

       

The Client	The Server
Computer and mobile devices on a network that requests resources from the server.	Computer that controls access to the hardware, software and other resources on a network and provides a centralized storage area for programs, data and information. Note: Server can be a mainframe computer used in a network environtment.

Advantages of client/server architecture:

• Centralized - Resources and data security are controlled through the server.
• Scalability - Adding or removing resources in the network can be easilly done by configuring the server.
• Better management of files - All files are stored in the server.
• Accessibility - Server can be accessed remotely and across multiple platforms including Windows, Linux and Mac OS.

Disadvantages of a client/server:

• Expense - Requires initial investment in dedicated server.
• Maintenance - Large networks will require a staff to ensure efficient operation.
• Dependence - When server goes down, operations will cease across the network.

Peer-to-peer vs client/server network:

Client server	Peer-to-peer
Computer/nodes request services from the server	Each individual computers act as both the service provider and the service consumer
software installation in the server only	Software installation for all computer
Easy to manage the resources in the network (server existence facilitate the distribution of the resources)	Difficult to manage the resources in the network
Higher cabling cost	Less cabling cost
Security control by server (centralized)	Security control by their own