In a Computer Based test, the examination is conducted using a server locally. Internet connection is not required to conduct the examination.

Typically a server is configured and connected to the local area network in the test center. Internet connection, if available at the test center, the question paper is downloaded few minutes before the administration of the examination. This questing paper is uploaded to the database of local server and the test is administered.

If the Internet connection is not available, question papers are generated on the fly as required by the client.

Irrespective of the process of question paper import, further process of test delivery at the test center is common, with or with out internet connectivity.

The questions may be randomized, answer options may be randomized as desired by the client.

If the Internet connectivity is available, the scores and responses of the candidate are uploaded to the central server. Else, the same are exported offline through email attachments.

For more details, you may read
Computer Based Testing
Building the Foundation for Future Assessments
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