Light Reflections

Looking back on downtown Seattle, from the boat that took us to the social event at Tillicum Village

As promised (apart from being a little late) here’s an update on what’s going on in the International Standards body for “customer premises cabling”. This group goes under the snappy little title of ISO/IEC JTC1 SC25 WG3, which rolls of the tongue quite readily once you’ve practiced it a few hundred times!

So, what’s it all about this time?
“Customer Premises Cabling” is the cabling that allows computers, and increasingly other ‘connected devices’ to communicate in offices, factories, data centres and homes. Much of this cabling is of course copper, with most desktop connections being made with Cat5E, Cat6 etc. twisted pair. However, for larger premises, the building backbone and campus backbone cabling will all be fibre optic. Fibre optic cabling also has a big part to play in data centres, where enormous amounts of information are moved around. Industrial networks also use fibre extensively to support longer distance communications and to provide immunity to electromagnetic interference.

…and what’s my role?
As mentioned in my last blog, I am the liaison officer from the IEC standards committee that deals with fibre optic systems (SC86C) and this group. This means that I can apply my knowledge of fibre optic systems to help make sure that they will work over the cabling systems that are being standardised upon by this group. In fact, historically there has been a bit of conflict between these two groups, with some overlapping of standards, particularly with respect to testing of installed cabling (regarded as a ‘system’ by IEC). So part of my role is to try and harmonise these different testing standards.
I am also appointed as a UK expert, and so I support the UK’s position, particularly with respect to the fibre optics issues that arise. The UK and its team of experts has been very pro-active in driving through many of the major developments in premises cabling standards.

So, what happened?
It was the first time that this group had met in conjunction with the IEC General Meeting and this meant that several additional fibre optics experts were able to attend, staying on from the previous week’s TC86 meeting, including the chairman of TC86, Umberto Rossi. This gave the group a better balance as it is usually dominated by ‘copperheads’ and so fibre optics issues are often sidelined and given little airtime. But at this meeting some good progress was made on fibre optics issues and interesting decisions made about the future directions of standards…

Key developments in the optical fibre ad-hoc meeting.
At last, a full revision of the standard (14763-3) for testing fibre optic cabling in premises networks is underway – the UK have been pushing for this for several years.
The work done by the UK FIA on Reference Grade Terminations was reviewed.
It was agreed that there was no requirement for the total Optical Return Loss to be specified or tested for optical fibre links and channels in premises cabling (although connector reflectance is specified).
The UK proposal to remove the Optical Fibre channel classification scheme was adopted, although implementation of this decision will take some time.
OM1 grade of multimode fibre performance (usually associated with 62.5/125 multimode fibre) will be removed from the main part of the standards and relegated to history (as an informative annex).

Other issues
There was a poignant moment at the start of the meeting as a minute’s silence was observed in memory of Stuart Reeves of ADC Krone, who was taken by cancer and sadly passed away on August 1st. Stuart had played a very active role in this working group, faithfully recording the minutes and documenting everything, including at times some very heated exchanges. His diplomacy, attention to detail and mastery of the English language were much appreciated by the group. The challenge of recording the minutes of this, often lively, group has been picked up by another Brit – best of luck to James Withey of Nexans!

Any questions?
As ever, if you have any questions or comments on the wonderful world of standards, please leave your comments here or get in touch with me Richard.Ednay@ott.co.uk

Some of the UK delegates at the ‘top table’ of the meeting – from the left, Mike Gilmore, Alan Flatman and James Withey, next to Water von Pattay the working group convenor.

A view of the full meeting.

This year’s General Meeting of the International Electrotechnical Commission (IEC) is the largest ever. Of course, being held in America, it just had to be bigger than anything that anyone else had done. There are literally thousands of technical experts here in Seattle from all over the world working on standards for all sorts of things, from dishwashers to fuel cell efficiency and, of course, fibre optics. The meeting has its own website at www.iec2010.org and even its own Facebook page that you can access from there.

So, what’s it all about and why am I here?
Well the main bits that I’m involved with are “fibre optic systems” where I’m nominated as the UK’s Principal Expert, although since I also have responsibility for optical amplifiers, active devices (e.g. lasers) and dynamic modules (ROADMs etc). Of course I also have an interest in the discussions of fibres, cables, connectors and passive devices and support other UK experts in these areas.

New Work
In the systems working group there are now many new challenges as fibre optic systems develop to support ever higher data rates and more DWDM channels. Some of the ‘hot topics’ up for discussion are:

• constellation diagram analysis – new ways of measuring quality of transmitted signals, when we are dealing with complex modulation formats where the information is coded into the phase of the lightwave as well as the amplitude
• in-band OSNR measurements, especially with closely spaced DWDM channels in ROADM networks using polarisation multiplexed signals

Maintenance
In addition to these new areas there is also the maintenance and updating of existing standards. I am the project leader for the second edition of the standards for testing insertion loss and return loss on singlemode cabling as well as PMD. New Committee Drafts will be issued on both of these following this meeting.

We are also continuing work on testing multimode fibre, encircled flux is a continuing subject of debate and a new ’round robin’ series of tests is going to be carried out. Contact me if you want to be involved.

Sensors
Another new are of work is on fibre optic sensors. There are many UK companies involved in this area and this also falls in the scope of GEL86/3. The Generic standard for these is being revised and a work programme is being initiated to produce a range of standards covering different ‘measurands’ and ways of measuring them.

Laser safety
The Technical Committee on laser safety (TC76) are also holding their meetings here, and I attended a joint meeting between the two groups, raising the issue of laser safety on fibre optic sensors and powering of remote devices over fibre, neither of which are covered by the current laser safety standards.

Liaisons
Another part of my role in the standards community is that of liaison officer between IEC SC 86C (fibre optic systems) and ISO/IEC JTC1 SC25 WG3 (!) – customer premises cabling. This group are meeting here in Seattle next week – so there will be news from that on “Light Reflections” next week.

As ever – I’m happy to answer any questions on this or hear your views…

A recurrent theme throughout many of the technical presentations at ECOC was “what happens after 100G”. Different aspects of this theme were addressed in a variety of symposia, workshops and technical sessions. It certainly seems that there will be some really interesting technology being deployed as we head towards Terabit data rates. An interesting summary was that we will be dependent upon 3 ‘M’ technologies, not 3M Technologies www.mmm.com but

Multi-level
Multi-core and
Multi-mode.

Multi-level refers to multi-level coding schemes such as QAM and/or OFDM that may be used to improve the spectral efficiency and therefore the capacity of conventional singlemode fibres.

Multi-core means that we can expect to fibres being constructed with many cores, each of which may be used for transmission. Results were presented on successful manufacturing and even splicing of such fibres. Investigations into cross talk between the cores were also presented.

Multi-mode refers not just to conventional multimode fibre, but the techniques that may be used to implement Mode Division Multiplexing in multimode fibre. This is the process of launching different channels into multimode fibre at different radial positions to increase the total capacity. An array of detectors is used to select different mode groups at the receiver and digital signal processing used to separate the channels and cancel out crosstalk between them. Successful transmission of 8Gb/s over 5km of multimode fibre was demonstrated.

Well here I am in Turin in Northern Italy for this year’s ECOC. On Sunday there was a series of workshops covering topical areas. I attended the morning session on Distributed Sensing Measurements, as in the IEC we are just starting to update the International Standard on fibre optic sensors. I announced this activity to recruit some more experts to help with this work.
I also attended presentations on what is being called “The Capacity Crunch” when the continuing growth in Internet traffic is not going to be matched by continuing improvements in fibre capacity as we approach the theoretical limits of conventional optical fibres. Also a series of presentation on approaches for Terabit transmission channels. Interesting topics for future training courses…
The day rounded off with a cocktail reception and the opportunity to catch up with friends from around the industry.

This year’s European Conference on Optical Communications will be held in Turin, Italy in September www.ecoc2010.org. The conference is one of the world’s major technical conferences where the latest developments in Optical Communications are presented and discussed (the other is OFC in the Spring in the USA). ECOC visits a different European city each year and I have attended every one of the last 10… in Munich, Amsterdam, Copenhagen, Rimini, Stockholm, Glasgow, Cannes, Berlin, Brussels, Vienna.
I find that regular attendance at these technical conferences is the best way to stay at the leading edge of fibre optics technology. The trends in key technologies can be tracked from the laboratory to field trials to commercial deployments. These key developments are integrated into our training courses such as the Certified Optical Network Engineer programme. The knowledge gained also helps in my work on the development of International Standards in fibre optics, to make sure that new standards are developed in timely fashion and that existing standards are updated as necessary.
Alongside the technical conference there is also the largest fibre optics exhibition in Europe, this provides a good opportunity for seeing new products, networking and meeting friends from around the industry. If you will be in Turin and would like to arrange a meeting then please get in touch.
This year ECOC will also coincide with the 21st Birthday of OTT, incorporated on 20th September 1989, so if you’re in Turin it would be good to see you at the Conference welcome reception on 20th September.

On a recent training course with some delegates from Saudi Arabia, we were inevitably discussing the weather. The delegates were pleased to be escaping the 52 degrees Celsius temperatures of Riyadh and didn’t mind the English Summer rain. There had, in fact been some severe downpours and locaised flooding a few miles from the training venue. All of this was shortly after a hosepipe-ban had been introduced and official ‘water shortage’ is still in place that has also closed a long stretch of the Leeds Liverpool canal between Skipton and Wigan. Interesting to note that there is no water shortage in Riyadh, a city of 6 million people in the middle of the desert without a river. All the city’s water is pumped from a de-salination plant 400km away on the coast – amazing what an investment in infrastructure can achieve!