Hjgfyuh

BT Scout

Sharing my IT experiences, Some which I learned the Hard-way and some the soft-way.

Friday, November 30, 2007

IT Infrastructure Layers

One of the top challenges faced by IT organization is managing the always growing and changing infrastructure. Divide and conquer, managing complexity by simplicity is the key for managing the IT infrastructure (or any thing for that matter.) To achieve this It is helpful to first divide or classify the infrastructure in meaningful areas or stacks or layers. This helps in managing the infrastructure by assigning or scoping responsibilities, isolating the problems to specific areas, making policies, handling security etc.

For a typical small to medium IT house the infrastructure could be classified into the following layers

1. Network layer.

2. Hardware layer.

3. Operating system layer.

4. System software layer.

5. Application software layer.

6. Business Service layer.

The Network layer includes the LAN, WAN, MAN and all the other devices like routers, switches, hubs and the cabling which form the network.

The Hardware layer includes all the physical hardware devices found in a typical computer center minus the network related hardware. Servers, desktops, SAN and NAS devices, Tape libraries, printers, scanners etc. all belong to the hardware layer.

The operating system layer includes the operating systems which run on servers and desktops like, Unix, Windows etc. Virtual servers also will belong to this layer.

System software layer includes the software that provides functionality required by the business applications directly and indirectly. This includes software like the database server, application server, email server, web server etc. Other softwares like DNS servers, antivirus Servers, authentication servers etc also belong to this layer.

Application software layer includes the software that delivers business functionalities, e.g. HR apps, Financial apps etc. Client and desktop software will...