N-GEN Communications Web-based Seminars ©NGCS

Seminar - An Overview of Communications Technologies

Module 2 - Data Communications Basics and Legacy Technologies                                                Slide 23 of 45 _________________                                                                                  __________

                                             Interface Standards

                                                OSI

                                                CCITT

                                                ITU

_________________                                                                                  __________

The European standard bodies include The International Telegraph & Telephone Consultative Committee (CCITT) and The International Organization for Standardization (ISO). The CCITT is now known as the ITU.

OSI - standard known for its seven layers for hierarchial identification of all data communications network functions. Layers 1-3 were originally proposed by the CCITT.

CCITT - previous name for ITU.

ITU - The ITU is a specialized agency of the United Nations which facilitates the global development of the telecommunications standards. It includes standards for telephone and radio communications. The ITU-T's V-series for data communications, G-series for voice signal digitization and H-series for video digitization and compression are well known.