The Message Security tab contains the following settings:
Require Encryption
This option indicates whether or not files received by Managed File Transfer should be encrypted.
Require Signature
A signed message contains a digital signature from the sender to further authenticate the message. If signatures are required, any message without a digital signature will be rejected.
Require Authentication
Require username/password or certificate authentication for messages uploads. If authentication is not required, Managed File Transfer will use the AS2 From ID in the message to find the Web User with a matching AS2 ID. Informatica recommends you select the 'Require Signature' option when authentication is not required.