The Client daemon uses the APPLID value specified. If the APPLID is not set, and the deprecated Application ID parameter on the CLIENT section is set to anything other than "*", this value is used.
If multiple Client daemon server connections are configured to a CICS server and you specify an APPLID, that name must be unique. If the name is not unique, attempts to connect to a server might be rejected because another connection has already been installed using the same APPLID.If the Client daemon wants to communicate with a given server over SNA, the APPLID might be overridden at the time the client is installed at the server by the Local LU name for the client. For TCP/IP connections, whether the APPLID is used to identify connections or not is server implementation dependant.
The APPLID parameter replaces the existing Client Application ID parameter. The Client Application ID parameter is supported for upgrade purposes, but is overridden by the new APPLID parameter.
The APPLID qualifier is not used for SNA and TCP/IP connections.