Fiber Characterization Standards – (ITU-T)
The international tensions Union – Telecoms division (ITU-T) makes recommendations on all aspects of international telecoms systems including fiber optics.
The G.650.1 & 2 standards cover the testing of fiber and cable in a factory environment.
In June 2007, an initial version of G.650.3 was published that was meant to cover testing of installed links. Unfortunately this version of the recommendation was very poorly written. Richard Ednay of OTT then joined ITU in order to re-write this Recommendation and the revised version was published in March 2008.
This second edition includes, for the first time anywhere in the standards, a definition of fiber characterization as given in the introduction to this module.
This Recommendation calls up the relevant IEC measurement standards for installed links detailed below.
AII ITU-T published, in-force, Recommendations are now available for free download from their website at www.itu.int
The International Electro-technical Commission (IEC) sets standards for products and defines test methods. The Technical Committee 86 deal with fiber optics. Under this there are three Sub Committee:
SC86A: – deals with fibers and cables
SC86B: – deals with fiber optic interconnecting devices and passive components (connectors etc.)
SC86C: – deals with fiber optic systems and active devices (installed links, amplifiers etc.)
The 61 280-4-x series covers tests on installed cabling links, including attenuation, return loss and PMD.
61 280-4-2: – covers attenuation testing of singlemode links. Richard Ednay of OTT has been appointed as project leader to substantially re-write this standard to produce an initial draft in October 2008. This will also include return loss measurements that were originally destined to (40 into a separate 61 280-4-3 standard.
61280-4-4: – covers PMD test methods for installed links and the Technical Report 61282-9 provides further guidance on PMD test methods.
I IEC 61 300-3-35: – is a new standard for fiber optic connector end face inspection, due for publication in 2008.
The IEC website is at www.iec.ch
There is a joint ISO/IEC Technical Committee 1 that deals generally with IT systems, Subcommittee 25 deals with “interconnection of information technology equipment” and undercoat there is a working group three that deals with “customer premises cabling”. Richard Ednay acts as liaison between this group and IEC SC86C.
Nowadays there is good harmonization of national, regional and standards international standards, so generally the relevant national standards bodies (such as the British Standards Institution in the UK, ANSI in the US etc.) and regional standards bodies (such as CENELEC in Europe) adopt the international standards and just add their own prefix to the standard to indicate that it has been ‘rubber stamped’ by them – egg. BS EN 60825 (laser safety).
In America the Telecoms Industry Association (TIA) and the Electrical Industry Association (EIA) have been active in developing and setting standards – and in the UK the Fibreoptic Industry Association (FIA) has developed some guidance notes. Often these bodies now feed their work into the international standards work
Having certified thousands of students and tested thousands of fiber spans, FiberOptic.com’s services division know as Adtell Integration is setting the standard for competence in performing fiber characterization and also education with the “Fiber Characterization Tech” course and certificate.
Having written the ITU-T G.650.3 Recommendation on fiber characterization then OTT is setting the standard for competence in performing fiber characterization with the “Certified Fiber Characterization Engineer” course and qualification scheme.