When troubleshooting any information system
It's best to follow the OSI model.
As a systems administrator for years i know that troubleshooting computer systems is like attending AA (Alcoholics Anonymous) meetings in that you must. I mean MUST! Work the steps.
The OSI model was originally developed to provide a structure to Protocol Development, however like any usefull tool you can apply it anywhere. It is especially helpful when troubleshooting computer problems. Start with the physical and then go on to reach the application. By utilizing this method you can further your knowledge and understanding of Computer Systems and thier problems.
This process can also be applied in any number of other places. Application Development, Car Maintenance. Etc...
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