he stan- dardization of information technology. ISO has done important work in the area of data communications and protocols, and IEC in the area of electro- mechanical (for example, connectors), environmental, and safety aspects. The organizations shown in Figure 1.7 work together closely to avoid duplicating effort and to avoid creating multiple standards for the same pur- pose. As a consequence, some ITU recommendations may contain merely a reference to an ISO standard. 1.5.6 Other Organizations Many organizations other than those just mentioned are working with stan- dards. Some of these are active in ITU-T and ISO, and many international standards are based on (or may even be copies of) the initial work of these groups. We introduce some of these as examples of standards organizations without official status (see Figure 1.8). The Internet Engineering Task Force (IETF) is responsible for the evolu- tion of the Internet architecture. It takes care of the standardization of the TCP/IP protocol suite used in the Internet. The Universal Mobile Telecommunications System (UMTS) Forum is an open organization of cellular system manufacturers. Its goal is to define a third generation cellular system that will receive worldwide acceptance and Introduction to Telecommunications UMTS Forum IETF (Internet) Telemanagement Forum (TMF) Figure 1.8 Examples of other standards organizations. ensure compatibility among equipment from different vendors. Unofficial forums are more flexible and can produce necessary standards on a shorter timescale than can official organizations. Their specifications are often used as a basis for later official standards. The Telemanagement Forum (TMF) is an organization of system manu- facturers that works to speed the development of network management stan- dards. With the help of these standards, telecommunications network operators will be able to control and supervise their multivendor networks efficiently from the same management center. Proposals are then given to ITU-T and ISO for official