4. General conclusion

It's not easy to come to an overall conclusion about the various transmission media and communications techniques, as there are many constraints and compromises to be made. Table 6 sets out the main advantages and disadvantages to be taken into account when choosing a communication device. Boxes marked with (–) show the disadvantages of row-based versus column-based communication areas and techniques, while boxes marked with (+) show the advantages of column-based versus row-based areas and techniques.