The National Institute of Standards and Technology (NIST) is the global reference for cyber security

 In 2005 NIST deprecated 56-bit cryptographic keys due to the risk of compromise by brute force attack

 STSA upgraded the STS security levels to 160-bit vending keys (published as STS600-4-2), which is approved by NIST for use up to 2045 (10^32 times stronger)

 It is essential that current prepayment systems upgrade to the new security level as soon as possible