Remote Backup allows you to use various Encryption Standards. Depending on the country you are in and the version of Remote Backup you have, some of these standards may not be available to you.
The old US Federal Standard
A much more secure form of DES
Probably the most secure of all. It uses a key length that is variable from four bits to 448 bits.
The new US Federal Standard. Remote Backup supports three levels of AES from 128 bits to 256 bits. 256 bit AES is very secure, but it is also slow.