Usually sensors would be close the a microcontroller so it is possible to use SPI or I2C or someother means to read/write them for communication. This is still true even if they are on another board connected to the backplane.
However, how would one get data from sensors that are more than a meter away. This will require one to use long cables that will have a lot of capacitance that will limit the data rate of transmission and make it more susceptible to corruption via noise.
How is this type of problem usually solved?