Reliability

This might be measured in terms of:

• availability, the percentage of a particular time interval that a system is usable;

• mean time between failures, the total service time divided by the number of failures;

• failure on demand, the probability that a system will not be available at the time required or the probability that a transaction will fail;

• support activity, the number of fault reports that are dealt with.

IOE maintenance group accounts system has been installed, and is normally Exercise 12.5

available to users from 8.00 am until 6.00 pm from Monday to Friday. Over a four-

week period, the system was unavailable for one whole day because of problems with a disk drive and was not available on two other days until 10.00 in the morning because of problems with overnight batch processing runs.

What were the availability and the mean time between failures of the service?

Project Management Made Easy

Project Management Made Easy

What you need to know about… Project Management Made Easy! Project management consists of more than just a large building project and can encompass small projects as well. No matter what the size of your project, you need to have some sort of project management. How you manage your project has everything to do with its outcome.

Get My Free Ebook


Post a comment