Vehicle communication systems and control systems

A vehicle control system comprising:

• a controller configured to communicate a message in a first protocol from a first vehicle in a vehicle system that also includes one or more of a second vehicle or a monitoring device in the vehicle system, the one or more of the second vehicle or the monitoring device configured to communicate a message in a different, second protocol,
• wherein the controller is configured to switch from communicating the message in the first protocol with the one or more of the second vehicle or the monitoring device to communicating the message in the second protocol with the one or more of the second vehicle or the monitoring device,
• wherein the controller also is configured to determine an operational restriction on movement of the vehicle system based on the communication loss that is determined,
• wherein the controller also is configured to obtain a transitional plan that designates operational settings of the vehicle system at one or more different locations along a route being traveled by the vehicle system, different distances along the route being traveled by the vehicle system, or different times, and
• wherein the controller is configured to automatically change the movement of the vehicle system according to the operational settings designated by the transitional plan to reduce the movement of the vehicle system to or below the operational restriction determined by the controller responsive to the communication loss being detected.

A method comprising:

• determining a communication loss between a first vehicle and one or more of a second vehicle or a monitoring device in a vehicle system that also includes the first vehicle;
• determining an operational restriction on movement of the vehicle system based on the communication loss that is determined;
• determining a transitional plan that designates operational settings of the vehicle system based on the operational restriction that is determined;
• and
• automatically changing the movement of the vehicle system according to the operational settings designated by the transitional plan to reduce the movement of the vehicle system to or below the operational restriction determined by the controller responsive to the communication loss being detected.