Friday, July 22, 2011
1. STAR TOPOLOGY
In this topology computer do not have any direct connection each other. This topology requires one central device to control communication between computers. All computers will connect to this central device or hub.
· Easy to install
· Network didn’t disturbed if one computer have a problem or disconnected
· Easy to find error on this network. Repair computer will not effect on others computer or network performance.
· Depend on hub, if hub broken then this network will down
· Require more cable because each computer directly connected to hub
· More expensive for cable and installation cost.
2. RING TOPOLOGY
In this topology, computer1 will directly connect to computer2 and so on. The last computer will connect to computer1. To communicate with computer3, computer1 should pass data through computer2. Computer3 will send back data through computer4 and so on until computer1 again (unidirectional).
· Easy to install
· Easy to add or delete device by only moving 2 connector
· If one computer failed than all computer in network will disturb
· When add new device all computer will disturb
Saturday, July 9, 2011
Operating system as interface between application and hardware have some characteristics, such as:
- Ability to run several applications/tasks at the same time.
- Example: Running Word while download file from Internet.
- Ability to communication with other separate computer/device.
- Example: Sharing file with another computer.
- Ability to exchange information among applications.
- Ability to access or accessed another system from separate location.
- Example: Windows Remote Access.
- Ability to detect new device when system has been running.
- Example: OS detect new printer.
- Ability to run application designed for another operating system.
- Ability to manage processor to run several instruction at the same time.