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Encryption How-To

Encryption is a process that uses mathematical algorithms to scramble data so that it can only be decrypted and read by someone who has the secret key it was encrypted with.

Whenever possible, IT set up automatic Encryption as part of our IT systems. For example, when you send an email to another UWL mail account, or if you access your UWL OneDrive over the internet, that connection is automatically protected with strong encryption.​

 

But we can’t encrypt everything automatically. Particularly risky is transporting data outside of the University network, by email or on a USB stick, so UWL policy is that personal, confidential, or sensitive data should not leave the University campus unless absolutely necessary, and if it does, it MUST be strongly encrypted. 


PASSWORDS

 

Before you encrypt some data you first have to choose a suitable password.

 

The recommended way to do this is to pick three random words and string them together. For example, Battery-Horse-Staple. (But don’t use that example!) This method gives a really strong password that is also easy to type.

 

If you’re sending encrypted data to another person, you'll have to send them the password too. This is where one of the most common encryption msitakes happens. NEVER send the password with the encrypted data or in the same way as you send the data. That includes emailing the encrypted data and then sending the password in a second emal .If a bad guy is intercepting the emails, they'll get both and the encryption is useless. If you're emailing the encrypted data, send the password by phone or instant message instead.

 

ENCRYTPING WITH OFFICE

 

Most of the time the files you will need to encrypt are Word documents or Excel spreadsheets. This is super easy to do, as Microsft have built strong encryption directly into these two applications.


Just go to the File tab, choose Info from the list, press the Protect Document button, and choose Encrypt with Password.




NOTE: This only works with Word (.docx) or Excel (.xlsx) format files. In particular, encrypting older .doc or .xls files with this method is not secure enough. Convert to the up-to-date format or encrypt with 7-Zip (see below).


NOTE: In Excel you'll see another option, "Protect Current Sheet". This does not encrypt the file - it's only used to protect documents against accidental changes.


ENCRYTPING WITH 7-ZIP


If you have to encrypt other files, or you need to encrypt multiple files and folders at once, we recomend using 7-Zip to create an encrypted zip file.


7-Zip is installed on all UWL PCs, and can be downloaded and installed for free on other PCs from https://www.7-zip.org for use on non-university machines.


With 7-Zip installed, right-click on the file, files, or folders you wish to encrypt, Choose 7-zip from the menu, and select "Add to Archive..."


In the dialog box that opens choose a name for your encrypted file, enter your password, and make sure that the Encryption method is set to AES-256. Then click OK to create the encrypted file.






NOTE: The older ZipCrypto encryption method is not strong enough and should not be used.


If you need further help or advice on encrypting your data, please contact the IT Service Desk​.

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