Telephony

ITU Standards Groups

• E Overall network operation, telephone service, service operation, and user interface
• G Transmission systems and media
• H Audiovisual and multimedia systems
• I Integrated services digital network (ISDN)
• O Specifications of measuring equipment
• P Telephone transmission quality, telephone installations, local line networks
• Q Call switching and signaling
• V Data communication over the telephone network
• X Data networks and open system communications
• Y Global information infrastructure and Internet protocol issues