On startup, there is no banner/welcome message from the server. The caller initiates the protocol by sending a welcome message to the server:

  1. For cars

MP-C <protection scheme> <token> <digest> <car id>

  1. For interactive user apps

MP-A <protection scheme> <token> <digest> <car id>

  1. For noninteractive batch apps

MP-B <protection scheme> <token> <digest> <car id>

  1. For servers

MP-S <protection scheme> <token> <digest> <car id>

The server responds with a welcome message to the caller:

MP-S <protection scheme> <token> <digest>