Bad passwords

Why and how do I change my password?

If at least one of the following points apply to you, you should change your password:

• Someone else knows your password, or you at least suspect that they do.
• You haven't changed it in a long time.
• Your password is hard to remember, even though you use it often.
• Your password can be easily guessed.

Why bad passwords are a problem

A bad password, like Qwerty12 or JohnDoe8 are easy for other people to guess. If someone has your password, it can be used to harm both you and NTNU. Possible scenarios are:

• Your account might be used to distribute spam mail. This would make NTNU extremely unpopular among other Internet users and providers.
• Your account might be used to spread illegal material like harassments, pornography or copyrighted material. If you're lucky, this will cause your account to be closed. If you're not, you may be reported to the police.
• NTNU's servers may be used for DoS attacks. This may result in being reported to the police.

How to make good passwords

Some tips for making passwords that are easy to remember, but hard to guess:

• Use upper-case letters in the middle of the password.
• Make an acronym of a sentence (this is a picture of a nice boat = tiapoanb).
• Replace numbers in dates with letters, and letters in words with numbers (0 = O, 1 = l, 3 = E, 4 = A, 5 = S, 6 = G, 7 = T etc.).
• Replace parts of words with numbers that sound the same (late = l8 etc.).
• Rotate parts of the password (samba = ambas).
• Type parts of the password in reversed order.

A good password is recognized by the fact that an outside person with a lot of information about you can not find it by combining for instance

• your name, username or birthdates of relatives / friends.
• symbols or descriptions of things that are easily associated with you.
• words or expressions that can be associated with you.
• simple keyboard combinations (qwerty, asdf, zxcv).
• words from any language.
• any of the above examples.

What is done at NTNU to prevent the use of bad passwords

The System Administrators run a password cracking software on all user accounts. If your password is cracked, your account will be closed, and you will have to get it opened again by visiting Orakeltjenesten to set a new and better password.