Backup Exec Supports Software supports a variety of data Encryption methods -
AES 128-bit Advanced Encryption Standard (AES) and 256-bit AES
Hardware encryption using the T10 standard requires 256-bit AES
FIPS validated 256-bit AES encryption (CMVP validation)
Support for LT0 4 T10 Encryption configurations
BitLocker Encryption Support
However, there is no mention about NIST 800-111 anywhere in te documentation as aready mentioned by Craig.