Replication Server 15.1 uses Sybase Common Security Infrastructure (CSI) for server or client authentication, cryptography for encryption and decryption of passwords that are stored in the RSSD tables, and key-pair generation to support extended password encryption.
Extended password encryption uses asymmetric key encryption, which allows Open Client applications with connection property CS_SEC_EXTENDED_ENCRYPTION enabled to connect to Replication Server. It also allows Replication Server to enable CS_SEC_EXTENDED_ENCRYPTION when connecting to other servers.
Asymmetric key encryption uses a public key to encrypt the password and a private key to decrypt the password. The private key is not shared across the network, and is therefore secure.