System Components PDF

Systems  Information Systems A computer system within a company or organization for sharing information. ( https://dictionary.cambridge.org/dictio nary/english/information-system )  Client/server system Client – computer that receives service - terminal devices Server – provide...

Systems  Information Systems A computer system within a company or organization for sharing information. ( https://dictionary.cambridge.org/dictio nary/english/information-system )  Client/server system Client – computer that receives service - terminal devices Server – provides service - host computers  Processing Modes: (1) Centralized Processing → a processing mode in which all processing is performed by a single computer (2) Distributed Processing → a mode in which processing is divided between multiple computers connected by a network  Who is a System Administrator Someone who takes care of the systems others are using. System Running Users able to work in Smoothly and Efficiently Easy and Efficient Manner  RASIS Measures used to indicate the safety and efficiency of the system. RASIS stands for: Reliability Availability Serviceability Integrity Security  RASIS Reliability This is measured as the MTBF (Mean Time Between Failures). This can be considered as the normal operation time of the system. Availability This represents the possible usage ratio of the computer system. This is computed as A = MTBF ( MTBF + MTTR)  Serviceability This represents the ease of maintenance of the computer system. This is computed as MTTR (Mean Time To Repair). This can be considered as the down time for the system. Integrity This represents the ability to prevent the data from being corrupted  Security This represents the ability to ensure the security of the data.  System Reliability Improved by ensuring that the system remains operational with no functions coming to a halt during operation. MTBF = Mean Time Before Failure  System Availability Percentage that indicates the level of uninterrupted availability.  Availability for Simple Systems Availability = MTBF MTBF + MTTR MTBF = Average time of continuous system operation MTTR = Average time to repair the system in the event of failure  Availability for Simple Systems Total operation time – Failure time Availability = Total operational Time  Availability Example: Availability  Complex Systems Series Systems Parallel Systems  Series Systems A system that operates only when all of the devices from which it is configured are operational.  Parallel Systems A system that operates as long as at least one device is operational. 4. Consider Figures below as example of configuration for communication systems connecting site 1 and site 2. In the figures, E through H are the units forming the communication paths. Their failure is p in all cases.