Page 333 - Optical Communications Essentials

Test and Measurement

Test and Measurement 323

TABLE 19.1. Summary of Key Standards Organizations and Their Functions
Standards class Key organizations Functions
Primary • NIST (U.S.) • Characterize physical parameters
• NPL(UK) • Support and accelerate development of emerging
• PTB(Germany) technologies (NIST)
Component testing • TIA/EIA • Define component evaluation tests
• ITU-T • Establish equipment calibration procedures
• IEC
System testing • ANSI • Define physical-layer test methods
• IEEE • Establish measurement procedures for links and networks
• ITU-T

Component testing standards define relevant tests for fiber optic component
performance, and they establish equipment calibration procedures. Several dif-
ferent organizations are involved in formulating testing standards, some very
active ones being the Telecommunication Industries Association (TIA) in asso-
ciation with the Electronic Industries Association (EIA), the Telecommunication
Standardization Sector of the International Telecommunication Union (ITU-T),
and the International Electrotechnical Commission (IEC). The TIA has a list of
over 120 fiber optic test standards and specifications under the general desig-
nation TIA/EIA-455-XX-YY, where XX refers to a specific measurement tech-
nique and YY refers to the publication year. These standards are also called
Fiber Optic Test Procedures (FOTPs), so that TIA/EIA-455-XX becomes FOTP-
XX. These include a wide variety of recommended methods for testing the
response of fibers, cables, passive devices, and electrooptic components to envir-
onmental factors and operational conditions. For example, TIA/EIA-455-60A-
2000, or FOTP-60, is a method revised in 2000 for measuring fiber or cable
length using an OTDR.
System standards refer to measurement methods for links and networks. The
major organizations involved here are the American National Standards
Institute (ANSI), the Institute for Electrical and Electronic Engineers (IEEE),
and the ITU-T. Of particular interest for fiber optics systems are test standards
and recommendations from the ITU-T that are aimed at all aspects of optical
networking. Within the TIA, the FO-2 Committee develops physical-layer test
procedures, system design guides, and system specifications to assist both sup-
pliers and users of fiber optic communications technology.
Interoperability and compatibility between different vendor equipment are
important concerns. The committee addresses the performance and reliability
of active components and systems, such as transmitters, receivers, amplifiers,
and modulators. Systems include single-mode digital and analog systems, opti-
cally amplified systems with dense wavelength division multiplexing (DWDM),
point-to-point multimode systems, and local-area network (LAN) applications.

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