N-GEN Communications Web-based Seminars ©NGCS

Seminar - An Overview of Communications Technologies

Module 5 - SONET, WDM, DWDM and B-ISDN Technologies                                                             Slide 34 of 76 _________________                                                                                  __________

                                               SONET Development Phases

                              Phase I - Establishing the physical parameters
                                and hardware requirements of the technology

                              Phase II- Defining the interworking standard for
                                different vendors equipment, operations and support
                                systems managing the network

                              Phase III - Defining message sets supporting the
                                application interfaces, the data communications
                                channels and user channels that provide security,
                                performance monitoring and alarm detection.

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Many private broadband networks were in place before the SONET initiative. A need to standardize the broadband network technology and simplify Operation, Administration, Maintenance and Provisioning (OAMP) of the broadband networks brought vendors, carriers and standards organizations together to develop the SONET standards.

MCI was the first carrier to propose, in 1984, to develop standards for an optical interface.

Bellcore, a consortium of Bell Operating companies, proposed the SONET concept in 1985 and encouraged vendors, carriers and R&D establishments to submit papers. 400 detailed technical proposals from 120 individuals and 50 corporations were submitted.

The CCITT started developing SDH standards in 1986 in Europe.

Phase I was completed in 1988.

Phase II and Phase II effort continued until mid 90s.

SONET equipment is available off-the-shelf from Vendors like Nortel, Lucent Technologies, Siemens and many more.