Safelisting in Mimecast – PSAT (Educate)

QuestionWhat is the CIDR format for Proofpoint Security Awareness Training IPs to allow safelisting in Mimecast?

AnswerThe CIDR format for our IPs:

52.202.140.133/32
54.173.248.25/32

Some safe listing requires that the Subnet Mask of the IP be specified (especially if you’re safe listing a range of IPs vs an individual IP). CIDR is a way to express that subnet mask without writing out all of the octets of the address (such as 255.255.255.255). In this case /32 is designating an explicit IP address, not a range.

See Safelisting Guide and Safelisting in Mimecast for additional information.