The Max DB X Server is the communication server for the database system. The X Server listens out for connection requests from clients such as database applications and database tools.
The X Server is necessary if a client is establishing a connection to a database instance located on a remote computer. The JDBC interface also requires the X server for local communication. Communication between clients and X Server can be encrypted with SSL/TLS in SAP systems.
The X Server can be used on all operating systems supported by the database system.
Concepts of the Database System,
MaxDB Security Guide, Using the MaxDB X Server Behind a Firewall