rent manufacturers. However, the involvement of many players, from manufacturers to network operators, meant that the standard was complex and difficult to implement. A number of the INWG members left and went to work on the Arpanet and further developed the connectionless philosophy. With funding from the US government the Internet architecture was developed using four distinct layers. With the slow pace of OSI standardisation many companies started using the TCP/IP approach for their immediate connectivity needs. Andrew Russel in his article 'OSI: The Internet That Wasn't' summarises the history of how OSI promise was never realised and how the IPapproach came to dominate the packet-switched telecommunications landscape. He writes about the major flaw of the OSI approach as follows: [The OSI's] fatal flaw, ironically, grew from its commitment to openness. The formal rules for international standardization gave any interested party the right to participate in the design process, thereby inviting structural tensions, incompatible visions, and disruptive tactics [9]. Case Study Questions What do you see as the relative merits of the 'virtual circuit' and 'connectionless' approaches to packet switching? Why do you think the network operators preferred the 'virtual circuit' approach? What are the merits of 'layered' design in designing the packet network? What were the reason for overall adoption of TCP/IP over OSI? How should an international standardisation be carried out? Broadband Telecommunications Technologies and Management Protocols Packaging data as described above provides a mechanism to send and receive information between two machines. However, a number of processes must be in place before actual com- munication of information may start. The receiver needs to know for example when a data transfer starts, which 'language' it uses, and at which 'port' it should be received. Within the received signal, the destination machine needs to know when a packet starts and when it ends; and detect whether there are 