database encryption questions

Question

We are using Sybase SQL Anywhere 11. We need to encrypt some of our tables in our database. I followed the instruction and did it. We selected the "strong" option with encryptionKey and AES256_FIPS algorithm. But there are something I am not clear about them.

1. It will require encryptonKey when we create the database, remove the database and start the database server but it will NOT require encryptionKey when we stop the database server and connect to the server to create tables and add data. Why there is NO encryptionKey asked when we connect to it or try to stop the server? I am doing something wrong?

2. don't know how to test the encryption? I still can see all plain text in the encrypted tables when I use Sybase Central tool. If somebody knows the database user name and password, he/she can connect to the database and read the content without the encryptionKey. is this right?

Answer 1

I can't speak specifically to Sybase's system, but database encryption in general is designed to encrypt at the file system level to prevent backdoor access to the database's data (i.e. reading the binary file and parsing it yourself rather than going through the RDBMS), not to prevent access or obfuscate data through the standard database interface (it's expected that you'll use your RDBMS's security mechanisms to do this).

Answer 2

Most likely the SQL Anywhere tool captures the encryption key when you first enter it (i.e. at server startup) and then stores it in memory to decrypt for other operations. As @Adam Robinson said, the data needs to be encrypted in the filesystem or there's a back door by taking the "analog solution" and just parsing the raw file, which is a nice segue to your second question...

If you want to test the encryption, try locating and opening the file outside of the Sybase tools and see if you can spot any identifiable data. I would start with a simple text search for a string (create a cell with a unique string you can search for) and make sure its not there in the encrypted file. To verify, you could also parse a non-encrypted version of the database and make sure that you can find the string there.