Prestel
In 1983, the Prestel messaging service known as “Prestel Mailbox” was launched, initially hosted on the computer known as "Enterprise", and later available from all IRC computers by means of a centralised messaging computer known as "Pandora". This facility extended the original day one concept of “Response Frames” whereby an end user could send a message back to the IP who owned the page via special pages, for example to order goods or services. The user’s name, address, telephone number, and date could be added automatically to the message when the IP set up the response frame by means of codes which triggered extraction of key data from the users account held on the IRC computer. Initially response frames were ingathered by an IP from each IRC individually, but later the facility to collect messages from all IRCs at the UDC from where they could be ingathered centrally was implemented, and with the introduction of Mailbox, they could be retrieved from any IRC.
TRAME
In year 1974, packet switching was a technology known only in research circles. The concept started by year 1968 associated to the USA's Advanced Research Projects Agency (ARPA) research project ARPAnet. The idea of applying the packet switching concept to electric utilities control communication networks first appeared in 1974 when the Swedish Power Utility Vattenfall started to create its TIDAS packet switching network and it was followed by the Spanish electric utility ENHER, which was targeting to telecontrol and automate its high voltage power network. With that goal ENHER created a specific team of people for developing both the packet switching network and the supervisory control and data acquisition (SCADA) system also named telecontrol system. In year 1978 the first four TRAME routers were already available and in year 1980 eight of them were already deployed and operating. The printed circuit boards (PCBs) controlling the communication lines were connected to a shared memory PCB allowing them to exchange data and messages. The project was developed together with its main initial application, the Telecontrol or SCADA system SICL ("Sistema Integral de Control Local") with which initially they shared a very similar hardware. By year 1980 the maximum link capacity was 9.600 bit/s which in 1980 was the maximum possible on a voice channel of 4 kHz width. These channels were the basic unit of the then analog communication systems in use. By that time power utilities used either telephone calls or low speed (below 1200bit/s) dedicated links for telecontrol, typically shared among ten high voltage electrical substations.