Use this entry to specify which hash algorithm is used to encrypt the signature.
- SNMP ID:
 - 2.27.14.21
 - Console path:
 - Setup > Mail > SSL
 - Possible values:
 - SHA1-RSA
 - SHA224-RSA
 - SHA256-RSA
 - SHA384-RSA
 - SHA512-RSA
 - SHA1-ECDSA
 - SHA224-ECDSA
 - SHA256-ECDSA
 - SHA384-ECDSA
 - SHA512-ECDSA