The ITU-T (Telecommunication Standardization Sector) is a permanent organ of the International Telecommunication Union (ITU). The ITU-T is responsible for studying technical, operating and tariff questions and issuing Recommendations on them with a view t
ITU-T Q.551-1994 history
1994ITU-T Q.551-1994 (WITHDRAWN) Transmission Characteristics of Digital Exchanges - Digital Exchanges Study Group 15; 32 pp