Method and system for updating card data of a navigation system

A method for updating map data of a navigation system in a vehicle, comprising the steps of:

• storing a first version of map data in a memory device of the navigation system;
• storing the first version of map data and a second more recent version of map data in a memory device of a map server;
• selecting a driving destination on the navigation system;
• transmitting destination data, which describe the driving destination, from the navigation system to the map server;
• determining a first route to the driving destination by the map server on the basis of the first version of the map data;
• determining a second route to the driving destination by the map server on the basis of the second more recent version of the map data;
• determining, by the map server, a degree of agreement between the first route and the second route by comparing the first route to the second route;
• transmitting a portion of at least one of the second version of map data and route data, which describe the second route, from the map server to the navigation system, based on difference map data between the first and second versions of the map data, when the degree of agreement between the first route and the second route is less than a threshold value;
• and
• suppressing the transmission to the navigation system of portions of the at least one of the second version of the map data and the route data that relate to routes that have not been driven by a user of the navigation system.