KB31094: New feature in MicroStrategy Intelligence Server 9.x: Ability to encrypt cache files stored to disk.

Starting with Strategy Intelligence Server 9.0, it is possible for administrators to setup encryption of report caches which are saved to disk. The encryption level to save report caches can be low or high and can be set at the project level. A report cache file is encrypted when it is unloaded from memory to disk and it is decrypted when it is loaded from disk into memory.
 
Note: Since the process of encryption and decryption needs to take place, the time to load an unload caches is higher when cache files are encrypted.
 
The encryption level can be chosen from the Project Configuration editor from Caching > Storage, as shown below:
 

 
Three options are available for the cache encryption levels on disk.

• None: With this option, it is the same as what was available in Strategy 8.x., The cache file is in binary format but there are some sections such as report SQL which are readable. Also, report data can be read from XML caches.
• Low (Simple): With this option, caches are stored on disk in a serialized and encrypted form using the TEA algorithm. This applies to regular report caches and XML caches.
• High (AES with 128 bit key): With this option, caches are stored on disk in a serialized and encrypted form using the Advanced Encryption Standard (AES) with 128-bit keys. This also applies to regular report caches and XML caches.

After choosing the required level of encryption, it is needed to reload the project. It is not required to restart the Strategy Intelligence Server.
 
Note that Intelligent Cube caches are encrypted if this setting is being used. However, Document caches in formats such as PDF, Excel etc. are not encrypted since the encryption settings are only applicable to report and cube caches.