This chapter discusses basic models used to structure communication systems and architectures. The ISO/OSI reference model introduced in Section 3.1.1 failed in practice because of its complexity, especially that of its application-oriented layers. Nevertheless, it still has some fundamental significance for the logical classification of the functionality of telecommunication systems. Though it was less successful in proliferating than expected, this model offers the proposed structure of telecommunication systems in similar form in the field of telematics.
Currently, the technologies and protocols of the Internet (TCP/IP reference model; see Chapter 13) have made inroads and are considered the de facto standards. The architecture of the Internet can easily be paralleled to the ISO/OSI reference model, as far as the four lower layers are concerned. The other layers are application-specific and cannot be compared to the ISO/OSI model.
However, the architecture and protocols of the Internet also represent a platform for open systems (i.e., no proprietary solutions supported by specific manufacturers are used in the network). In addition, the development process for new protocols in the Internet by the Internet Engineering Task Force (IETF) is open for everyone and is designed so that the best and most appropriate technical proposals are accepted.
