 occurs within their countries. The modified standard is then adopted every member. This fee is made up of a number of units of contribu- by the Technical Assembly, using a system of weighted voting, as tion, the number of units relating to the turnover of the organisation described below, if required. or, in the case of Administrations, to the Gross Domestic Product of European standards 22/19 the country. The value of a single unit is set every year based on the estimated costs for the coming year. Table 22.10 Some early NETs In addition voluntary contributions are obtained for a voluntary account, to cover costs of any special work undertaken with the Description Technical Assembly's agreement, but which is not funded by the above. This includes translation costs, the official languages of the X.21 Access Institute being English, French and German. The Institute obtains X.25 Access revenues from sale of publications, and from fees charged to ob- ISDN Basic Access servers. PSTN Basic Access 22.4.4 Digital Telephony X.32 Access As stated earlier, an ETSI standard (ETS) is voluntary until it is converted into a NET (Norme Europeene de Telecommunication). ISDN Terminal Adapter This was originally done by weighted voting in TRAC, an organi- Digital Cellular Radio Mobile Access sation within CEPT. The membership of TRAC is limited to those European countries who have signed an MoU to give legal force to Mobile Terminal a NET as a technical requirement within their country. It includes Modem Category 1 all EC member countries, and applies to all telecommunication Modem V.21 Administrations, to licensed public network carriers, and to equip- ment suppliers who want to attach equipment to any public network Modem V.22 within these countries. In addition Administrations and network Modem V. 22bis operators must use the relevant NET specification when procuring terminal equipment, unless it is a direct replacement for an earlier Modem V.23 equipment. Modem V.32 NETs are basically of two types: access NETs, which specify 