As the person responsible for the day-to-day system management,
you play an important role in ensuring the security of your system.
Therefore, you should familiarize yourself with the security features
available with the OpenVMS operating system and implement the features
needed to protect systems, users, and files from damage caused by
tampering. Effective operating system security measures help prevent
unauthorized access and theft of proprietary software, software
plans, and computer time. These measures can also protect equipment,
software, and files from damage caused by tampering.
Security problems on most systems are generally caused by
irresponsibility, probing, or penetration. The tolerance that your
site might have to a breach of security depends on the type of work
that takes place at your site.
A secure system environment is a key to system security. HP strongly
encourages you to stress environmental considerations when reviewing
site security.
In the OpenVMS operating system, managing system security
is concerned with three major areas:
Controlling access to the system;
for example, interactively, through batch processing jobs, or over
the network
Controlling access to information and resources
that are kept on the system; for example, files, application programs,
or system utilities
Managing the auditing system so security-relevant
events are logged, the log file is reviewed on a regular basis,
and the log is kept to a reasonable size
The following sections describe measures to control access
to your system and its resources.
HP OpenVMS System Manager's Manual, Volume 1:... 
Security Considerations