fibresystems.org blog
November 7, 2008
Gemfire on ice
Could Gemfire be the first casualty of the credit crunch? The integrated optics firm is reportedly running short of cash as investors get cold feet and customers push out their orders.
As a result it has abruptly closed down its facility in Livingston, Scotland, with the loss of 250 jobs, says this BBC report. (You may recall that the Livingston plant is the home of the former silica-on-silicon firm Kymata, which was sold to Alcatel Optronics, then to Avanex, and finally to Gemfire.)
The fiesty Scots don’t appear to be very happy at this treatment, claiming that the Livingston outfit was the most profitable of the three Gemfire locations, and the order book was full, according to this article in Scottish daily The Herald.
However, UK labour laws apparently don’t allow the option of putting the company on ice for two weeks, the tactic the company has employed at its two US locations to see it through the tight spot.
If — and I’d say that’s a fairly big if in the current climate — Gemfire manages to conjure up additional funding, either in the form of a new investor or a bridge loan from customers, then it may try to reopen the Livingston factory.
October 27, 2008
Innovating in a crisis
In the midst of the turmoil in the banking industry, and the seemingly endless stream of bad news from Wall Street, it’s easy to get stuck in a negative mindset. But a couple of articles that I saw recently highlight the fact that one man’s bad fortune can be another man’s opportunity.
For a kickoff, Paul Graham, essayist and co-founder of Viaweb, the first application service provider, writes about why to start a start-up in a bad economy. Many folk are predicting that this economic slowdown could be as bad as the seventies, he notes… that’s when Apple and Microsoft were founded.
Investment guru George Gilder also provides some welcome relief from the doom and gloom with an article in Forbes in which he talks about an upcoming creativity boom. “The real source of all growth is human ingenuity and entrepreneurship, which often thrive in the worst of times,” Gilder points out. Which company emerged victorious from the telecoms crash of the early 2000s? Google.
October 16, 2008
ECOC: the 40G supply chain
A few more things I saw at ECOC are worth noting, albeit belatedly, and a bunch of them were about 40 Gbit/s components.
In his market focus presentation, Kim Papakos from Tellabs highlighted single source components as a real problem for systems vendors wanting to build 40 and 100 Gbit/s networking gear. Ideally companies like Tellabs would like at least three sources on the market, so that if one supplier goes belly up, there are still multiple sources available. That requirement is passed down to them from their operator customers.
Loi Nguyen and Lian Zhao from Inphi
The lack of suitable off-the-shelf parts for 40 Gbit/s has often been cited as one of the factors that delayed the adoption of 40 Gbit/s networking. Nevertheless, it surprised me to find that there are still quite a lot of 40 Gbit/s components that are only made by one company, and some that simply aren’t available at all.
A case in point, Inphi and Sierra Monolithics joined forces to create the industry’s first reference design for 40 Gbit/s DQPSK (differential quadrature phase-shift keying) modulation. The booth demo showed interoperability of Inphi’s 40 Gbit/s modulator driver with Sierra Monolithics’ SerDes multiplexer/clock multiplier unit.
As I understand it, Inphi is the sole supplier of DQPSK modulator drivers, while Sierra Monolithics is currently the sole supplier of 40 Gbit/s SerDes. That’s because high-speed, high-voltage chips are difficult to make in silicon, so vendors have to resort to other materials systems.
Inphi’s DQPSK modulator driver for example, which has to output two streams of 20 Gbit/s at an amplitude of 8 V, is made out of gallium arsenide. (For comparison, networking chips in other roles typically require 1 V.) Meanwhile Sierra Monolithics makes its present generation of chips out of silicon germanium using IBM’s 7HP process.
The supply situation will improve over time of course — CoreOptics announced a 40 Gbit/s SerDes chip earlier this year, and AMCC is possible also working on one. But right now the components supply chain isn’t complete at 40 Gbit/s, let alone 100 Gbit/s.
In fact, Loi Nguyen, co-founder and vice president of technology for Inphi, told me: “Nobody has a TIA [transimpedance amplifier] for 40 Gbit/s DP-QPSK [dual-polarisation quadrature phase-shift keying].” The TIA sits on the recieve side in the equivalent position to the modulator driver on the transmit side, and amplifies the weak electrical signal coming in from an optical detector before passing it to the SerDes.
DP-QPSK is the modulation format selected by the Optical Internetworking Forum (OIF) for 100 Gbit/s components, which is supposed to hit the market in 2010, and yet it’s still not possible to get standard parts for the previous speed incarnation. Clearly components vendors have a lot of work to do.
October 8, 2008
OIDA Photonic Integration Forum
fibresystems.org is delighted to welcome Jeff Ferry, Director of Communications for Infinera, and a former journalist, as a guest blogger this week. Jeff will be reporting on the OIDA’s Photonic Integration Forum, which is the first industry conference dedicated to the commercial development of photonic integration technology. As such it marks an important step forward for this technology area. The conference has been co-organised by OIDA and Infinera.
The conference attracted an impressive 60 experts in photonic integration, says Jeff, filling the room to capacity at the picturesque Monterey Hotel and Spa, perched up against, and partially built out over, Monterey Bay, 100 miles south of San Francisco. So without further ado, over to Jeff…
Tuesday, 7 October, OIDA Photonic Integration Forum, Day One
By Jeff Ferry
Photonic integration
The two most interesting themes of the conference’s first day were scalability and power consumption. The debate over scalability turned into a discussion of integration on indium phosphide vs. integration on silicon. The indium phosphide (InP) supporters, led by Infinera, have the benefit of having large numbers of photonic integrated circuits deployed by real customers. According to the chart shown by Infinera co-founder Dave Welch, Infinera has accumulated 101 million hours of PICs running in live networks without a single failure, with each PIC pair integrating 60 devices. That translates to a FIT rate (reliability measure) of 9, which is better than many single lasers and modulators in the market today. “Everything gets better when you integrate, reliability, yield, performance, and costs,” said Welch.
Later in the day, Infinera PIC engineer Randy Salvatore provided some insight into how Infinera has achieved its reliability and yields, describing the six stage statistical process control methodology that Infinera borrowed from the silicon industry and applied at its PIC fab. According to Salvatore, when compared to silicon chips and specifically Intel’s well-documented history, Infinera has in the last two years made progress equivalent to six years’ worth of Intel progress, moving from defect density numbers equivalent to Intel’s in 1987 to numbers comparable to Intel in 1993. This, said Salvatore, is the silicon learning curve successfully applied to InP.
Professor John Bowers of University of California at Santa Barbara emerged as the most charismatic advocate of silicon photonics. He showed slides on his UCSB team’s progress in several areas, including high-quality photodetectors made from silicon germanium, hybrid lasers made from a combination of III-V materials and silicon, and on the manufacturing side, they’ve reduced the time required to bond the two materials together from 12 hours to as low as 10 minutes — an important step towards making the technology practical, reliable, and commercial. Bowers said that silicon CMOS technology makes it possible to reduce device size to the point where it becomes possible to get as many as 125,000 die sites (i.e. chips) on an 8 inch wafer. All those developments go towards making silicon photonics PICs more cost-effective than any other material, said Bowers. “Infinera is doing a great job, but the potential for lots more scaling exists,” Bowers said. “The platform for VLSI PICs exists. Millions of devices [on a chip] is possible.”
The next speaker, Meint Smit, of the Technical University of Eindhoven, brought a touch of Dutch pessimism to the conference. He said that neither InP PICs nor silicon PICs could get beyond 1000 devices on a chip before the power consumption of the lasers would make the devices impractical. He presented an alternative, based on “digital nanophotonics,” two tiny “microlasers” working in tandem to generate a single lightstream with far less power dissipation. He has labeled this technology “indium phosphide membrane on silicon” or IMOS, and said it allows for a much larger number of lasers per chip. His prediction was that IMOS technology could push PIC complexity to 100,000 devices on a chip.
Both IBM’s Clint Schow and Sun Microsystems’ Ashok Krishnamoorthy focused on the same problem: the growing power consumption of high-performance microprocessors in today’s multithreaded, multicore computer servers. According to Schow, IBM’s Cell processor (developed in partnership with Sony and used in Sony videogame controllers) consumes 100 W of power, with 30% of that total going to moving data either on and off the chip, or between the cores, buffers, and memory on the chip. Krishnamoorthy said that the growing power of servers in the data center has created a situation where power consumption has reached levels of 10 kW per square foot. Adding more threads and more cores simply adds to the need to move data around the processor chip or between chips, adding further to power consumption. “This is not sustainable. We are in a vicious thermal cycle,” he said.
Both men said substituting optical interconnects for copper can make a big contribution to reducing power consumption. Krishnamoorthy said Sun has built a chip with 256 VCSEL lasers, each one operating at 1.25 Gbit/s and consuming just 12 W. Cost is also critical, so an optical interconnect needs to be able to move 1 Gbit/s of data 100 meters for a cost of around $2.
Schow presented an equally ambitious vision, not just optical interconnects based on PICs, but an “optical printed circuit board,” based on polymer waveguides, onto which PICs and other optics devices can be placed on a volume production line just the way electronic boards are built today. He said IBM has demonstrated transceiver chips with 16 lasers and a data rate of 160 Gbit/s, based on hybrid technology. He said III-V materials are needed for the optical reach, and better manufacturing techniques need to develop, including better packaging techniques to align arrays of fiber to arrays of lasers. “Integration is key, and we need the right mix of hybrid, and monolithic,” Schow said.
Eli Yablonovitch of UC Berkeley, and an adviser to California start-up Luxtera, described Luxtera’s first product, the Blazar fiber optic cable, and showed that this company is very focused on cost. Blazar looks something like a USB cable, but inside the connector at each end of the cable is an optoelectronic transceiver based on silicon photonics technology that converts 4 x 10 Gbit/s of data from electronics to optics and back again. It has low power consumption and cost approaching that of copper. To develop this product, which is scheduled to begin volume shipments this quarter, Luxtera made significant innovations in grating couplers and developed a high-yield, high-volume manufacturing process. Applications are initially in high performance computing, but according to one conference attendee, the optical cable also has consumer electronics applications. If you need to get that HDTV signal from the cable box out to the backyard, this could be your answer.
NOTE: The views in this blog are the author’s own and do not represent those of Infinera or any other organization.
October 7, 2008
Avanex swings the axe
Despite the prevailing gloom in the financial sector, vendors exhibiting at the European Conference on Optical Communications (ECOC) were generally upbeat, with one notable exception — Avanex.
Well, a possible reason for the glum demeanour of the employees on its booth just came to light. According to an 8K form filed last week Avanex plans to lay off about 8% of its work force, or 47 employees by the end of this month. The company also plans to close its Melbourne, Florida facility and transfer the product lines, inventory, and fixed assets to its France or China offices. What’s more, the executive officers have voluntarily agreed to a 10% reduction in their salaries beginning October 2008.
Avanex seems to be tightening its belt in anticipation of reduced sales in the later part of this year. Although the company posted 5% sequential growth for Q408, which ended on 30 June, it issued guidance for a substantial sequential revenue decline for the following quarter. The company has yet to find a permanent replacement for former CEO Jo Major, who was axed in August, and it’s stock has reached an all-time low.
September 26, 2008
Traffic control problems
Friday 26 September 2008, Day Four, Carrier Ethernet World Congress, Berlin
TRAFFIC CONTROL PROBLEM CAUSES NON-DETERMINISTIC PLANE MANAGEMENT
By Mark Lum
It’s the fourth and final day of CEWC, somewhat diminished in quantity of delegates, if not in quality, and your diarist arrives to find himself — and more importantly, Verizon Business — in hot water for yesterday’s apparently contentious diary.
In case any readers missed seeing that, and in order to cool the water, I will more clearly re-state Verizon’s bold comment as “There is no Carrier Ethernet access service standardisation”. A rather evident situation, it seems to me! And one that is being addressed by important developments such as the MEF’s E-NNI and wholesale access interconnect, Ofcom’s Ethernet ALA requirements, and numerous other related standards and carrier activities that delegates have heard about during the week. The big question: how much will carriers want to align the very services that they compete on? A difficult area, certainly, but the industry’s prognosis is positive and further progress should be made over the coming year.
Today’s focus is “Future Ethernet” and whilst the headline “MPLS versus PBT” technology war has subsided, there is plenty to keep the remaining delegates interested, including presentations from: Cisco, Ericsson, Huawei, Juniper, Nortel and closing with a panel debate on options for Ethernet control and management and a synchronisation masterclass from Semtech.
Alert delegates will have heard several speakers mention SyncE — Synchronous Ethernet — during the week and be aware that synchronisation is a key requirement for mobile, and other, applications. As technical editor for several timing/sync ETSI and ITU standards during the 1990’s, I can tell you this is rather an arcane subject, but one of critical importance for Carrier Ethernet and packet transport evolution. For experts only, perhaps?
Away from the bright spotlight of the opening days, we hear considered presentations helping to put the various Carrier Ethernet technologies into some perspective. Including a full acronymic spectrum encompassing GELS, T-MPLS, PBB-TE, BGP, MPLS-TE, IGP, CL-PS, VPWS, LDP, MPLS-TP, PLSB, CO-PS, PBB/MPLS, VPLS, and too many more to list.
MPLS-TP has received vocal support during CEWC as the way to simplify packet transport, and delegates learn now that 18 technical drafts have been identified to date, requiring development and agreement. Proponents tell us that they foresee a dynamic control plane, and also that carriers’ existing TDM-oriented management systems will not, in fact, be suitable. On the face of it, it seems that complexity is needed to deliver simplicity! Your diarist has been variously informed that MPLS-TP standardisation may take 9, 12, 18 months or even 2 years. Let’s see how the progress goes.
Well, that’s it for another year: there is more at CEWC than can possibly be written about in a few diary pages, but I hope you’ve enjoyed a few glimpses here. Thanks for reading! Meanwhile, I and other UK residents are hoping that the Heathrow air traffic control problems of yesterday have been resolved, and we will find our way home in a deterministic fashion. I’m sure there is some telecom analogy to be drawn, but I leave that as an exercise for the reader.
Carrier Ethernet World — complete with MEF technical briefings and EANTC equipment interop showcase — travels to Singapore this November for its Asia-Pacific debut edition. In conclusion from the MEF’s official congress, notable progress has been made in scaling Carrier Ethernet and the market looks set to continue its strong growth in the coming year. See you in Berlin again for Carrier Ethernet World Congress 2009.
Read more of the CEWC Daily Digest, Day Four >
September 25, 2008
Hegel’s dialectics give way
Thursday 25 September 2008, Carrier Ethernet World Congress, Berlin
HEGEL’S DIALECTICS GIVE WAY IN THE SHADOW OF BRANDENBURG’S GATE
By Mark Lum
Brandenburg Gate
Berlin’s iconic Brandenburger Tor and Reichstag are literally just around the corner from the Maritim hotel and it’s a cool and sunny walk out to a breakfast cafe before today’s conference, to consider the depth of history present in this magnificent city.
A far cry indeed from the technical and business discussions of this week. Carriers tell me they are heartily glad that the heat of the recent technology wars is now dissipating: perhaps “storm in a teacup” would be the most polite verdict! Operators have bigger fish to fry, and are happy to still have a choice of Ethernet and MPLS technologies and vendors to support applications such as IPTV and access — today’s principal topics. I learn that residents in Slovenia are offered by T-2: a 14 Euro/month 10M/10M broadband service plus 140 channels of IPTV at 12 Euro/month using Carrier Ethernet. Perhaps one day, we may all be so fortunate!
At the main event, it’s something of a slow start, as many delegates are perhaps in a leisurely mood after being treated to vendor hospitality alongside a large display of vintage cars. I can only say that latecomers missed a fascinating exposition from MTN Nigeria, the first of today’s service provider speakers including Belgacom ICS, BT Openreach, Deutsche Telekom, Magyar Telekom, NoaNet, Verizon Business and Virgin Media.
A case study in modern mobile network growth, MTN has grown to support 19 million subscribers in just 7 years, including a substantial proportion of 3G. Building entirely on PDH microwave access/backhaul with an SDH optical and microwave backbone, MTN continues to build about 180 new sites per month. In MTN’s view evolution to Ethernet is certain, but it must be a gradual implementation whose starting time is still yet to be decided (perhaps somewhat disheartening to hear for the cheerleaders of Ethernet backhaul).
Over in Ofcom’s parallel seminar on Ethernet Active Line Access, I find a sizeable number of delegates deliberating a fundamental question: how best to ensure competitive NGA (next generation access) using Ethernet? High-level speakers from the European Commission, HanseNet, IFNL, KPN plus industry bodies Broadband Forum, ITU and MEF are presenting their insights and thoughts. Ofcom is seeking to catalyse standardisation of Ethernet Access in the UK, perhaps beyond, and has published a new regulatory consultation on technical requirements.
I was relieved to hear one speaker — thank you, BT Openreach — to at least mention Green Telecoms, and the need to reduce power consumption. Any delegate who received a free sauna from the 16-rack CEWC interop showcase can relate to that. Trend-setting carriers such as BT and Verizon, are leading the way in this area, and I trust that others will follow in the next year.
Verizon Business gain today’s “open and honest” award. Perhaps emboldened by its award as MEF European service provider of the year for business innovation, they stated “there is no such thing as Carrier Ethernet: there is no standardisation”. I think they have a point! In the good old days, you knew exactly what an E1 or STM-1 circuit was: the specs were laid out, with no deviation. These days, an “Ethernet access service” can mean almost anything. Flexibility is surely a good thing, but perhaps not if you’re a competitive carrier trying to offer consistent services around the world.
Looking back on today, it feels that the conference has moved a long way from the Kompella’s “Purple Line” and Hegelian Dialectics of Day 1. In the carriers’ world, the principal challenge is growing fancy new applications using cranky old access networks. It was always thus! But from Berlin, Carrier Ethernet is rising to the challenge as it continues to scale in momentum.
As the exhibition packs up around me, join me at the last day of Carrier Ethernet World Congress 2008, tomorrow.
Read more of the CEWC Daily Digest, Day Three >
September 24, 2008
An inconvenient technology
Wednesday 24 September 2008, Carrier Ethernet World Congress, Berlin
AN INCONVENIENT TECHNOLOGY AND CARRIER ETHERNET MATURITY
By Mark Lum
Day 2 at CEWC, and with a full exhibition area and a streamed conference agenda concurrently covering mobile applications and business services, delegates have more than enough to keep themselves busy. There’s a notable buzz and much enthusiasm. New media is much in evidence and several speakers — your diarist included — have been captured on vox-pops by a roving camera.
Yesterday’s closing panel session of 8 leading vendors — plus 1 vacant chair! — presented a surprisingly united front that MPLS is the chosen route to support Carrier Ethernet services and applications. Despite the singular support of Extreme Networks for an Ethernet/PBB/PBT/PBB-TE approach, all other vendors were determined that MPLS is the only true way forward for Carrier Ethernet services.
A conclusion reinforced by BT which presented an update on its 21CN program without mentioning PBT, a key feature of recent years. 21CN has been “slightly re-focused” to support new services based on customer requirements, rather than PSTN replacement. BT now has an ambitious program to expand its Ethernet services coverage from 106 UK POPs to 600 by May 2009.
And yet, in a timely newswire yesterday, we see an announcement from the US that Sprint has selected Ethernet/PBT for their mobile backhaul applications. Reminding us that this, after all, is what PBT was originally created for, rather than a replacement for MPLS. One should never manage business strategy by press release, but perhaps other carriers will also inconveniently choose Ethernet/PBB/PBT solutions for applications such as access and backhaul.
Whilst there has been much talk of simplifying MPLS at lower cost, your diarist has seen few concrete results in this area. Sprint is said to focus on operational excellence, so its selection of Ethernet/PBT for backhaul will doubtless receive closer attention from the industry at large.
So enough technology, already! Carrier Ethernet is a maturing market, signified by innovation moving away from raw technology towards operational and management areas such as service automation. And also, it must be said, signified by continuing supplier consolidation.
Today’s conference has focused on mobile applications — where the need for future Ethernet-based microwave and backhaul systems is certain (if only to save the operational costs of cabling in the RAN and on a longer timescale than many seem to expect). And also business services — where much effort is focused on ensuring that Carrier Ethernet services meets enterprise requirements. “Enterprise Ethernet”, anyone?
VPLS very much to the fore, as might be expected, and an increasing interest in Ethernet over Copper. This is surely the major opportunity in front of Carrier Ethernet: the long-term transition of a huge number of private/leased line TDM services to Ethernet. But first, the industry will need to sort out the best way to support Connection-Oriented Ethernet services. Back to inconvenient technology again!
Across the topic streams, there were over 20 sessions today: surely more than any delegate can rationally assimilate! Service provider presentations from Belgacom, Cable & Wireless, Orange, Telecom Italia, Teragate, THUS and Verizon help to keep our feet on the ground.
Many delegates here relate an extremely busy day, characterised by meetings and discussions, punctuated with presentations of choice. Tomorrow in Berlin promises to bring more of the same as we focus on access, IPTV and packet-optical; plus a special Ofcom-led seminar on Ethernet Active Line Access.
Read more of the CEWC Daily Digest, Day Two >
ECOC: From the show floor
ECOC exhibition
Components vendors are out to prove that Infinera is not the only game in town when it comes to photonic integrated circuits (PICs). At the European Conference on Optical Communications (ECOC) there are a couple of demos worth pointing out.
First up, tunable laser maker Santur is showing a 100 Gbit/s PIC made out of indium phosphide. The device is a variation on the company’s tunable laser technology, which contains an array of 10 lasers with a MEMS device to select the output from one of them. In the 100 Gbit/s PIC, the MEMS device has been replaced by a passive multiplexer, which combines the light from all the 10 Gbit/s lasers (running at the same time) onto a single fibre.
The company claims that its device offers a simple solution for distances up to 10 km, in access networks and short reach interconnects. It could potentially be cheaper than the 4x25 Gbit/s or parallel optics schemes that are also being considered for 100 Gbit/s applications.
But Centre for Integrated Photonics (CIP), the former research activity of BT, has gone one better with a demonstration of a 32-channel PIC.
CIP’s photonic integration technology, which was unveiled here at the show is based on hybrid integration platform called HyBoard. Indium phosphide active components are mounted onto silicon “daughterboards”, which are then flip-chip mounted onto a silica-on-silicon motherboard containing optical waveguides to connect all the components. The platform is self-aligning, and has been designed so that it can be outsourced to a contract manufacturer if volumes require it.
CIP’s demonstration, which contains continuous-wave (CW) lasers, showed how the channels could be turned on and off individually, how the power could be balanced across the channels, or tilted to suit the input to an optical amplifer. Inside the package are two monolithically-integrated arrays of 16 lasers each, mounted side-by-side on the HyBoard platform.
The PIC in its current form is intended for WDM-PON, where it could provide a colourless solution for customer premise equipment (CPE). In this application, an array of CW lasers located at the headend sends light down the fibre to the CPE, which contains a reflective SOA that puts the data onto the wavelength, and reflects it back up the fibre to the optical line terminal.
CIP says that the concept could be extended to create a 160 Gbit/s PIC, containing 16 channels at 10 Gbit/s, simply by adding modulators to the package.
September 23, 2008
Carrier Ethernet grows up
Tuesday 23 September 2008, Carrier Ethernet World Congress, Berlin
CARRIER ETHERNET GROWS UP AND SCALES UP
By Mark Lum
Industry analyst Mark Lum
Welcome to my Carrier Ethernet daily diary from the 1st day of the MEF’s World congress here in a damp and rainy Berlin! We’re here to understand more about the market, meet colleagues from around the world, and debate the further evolution and growth of Carrier Ethernet services, networks and applications. A somewhat abridged diary due to my chairman’s duties today, I’ll have a more considered diary tomorrow.
Today is all about scalability with a Carrier Ethernet switch/router market worth over $5bn, according to IDC. As MEF founding president Nan Chen presented in his opening address, the technical and operational foundations of Carrier Ethernet have been put in place over the past four years and the MEF is now making progress in more complex areas such as E-NNI and security, and opening up new applications such as mobile backhaul and wholesale access interconnect services.
The heat of the technology and protocol wars fought over the past couple of years seems to have dissipated. But can victory be declared or is this just a lull in activities while the various factions regroup armed with new standards? What are carriers really looking for? Speak it softly, but I understand that even SDH may not be as dead as many here assume.
MPLS simplification is the technology theme, in order to provide an effective packet transport network. With the mutation of T-MPLS to MPLS-TP - and formal RFCs expected in 12-18 months’ time - and ongoing standardisation of PBB-TE, the overt technology wars have definitely abated since last year’s CEWC. I suspect many are waiting to see how the MPLS-TP work will meet the operational needs of carriers. In the meantime, PBB-TE focused vendors will not stop their marketing efforts, so I expect another interesting year ahead as the path towards Connection-Oriented Ethernet continues to be mapped out. I also expect a lively 9-vendor panel debate, covering the complete spectrum of Carrier Ethernet technologies.
Once again EANTC has produced another must-see Carrier Ethernet interoperability showcase. Larger than ever, 28 vendors have worked to set up a fully interworked test network comprising over 110 different products with over 330 separate test items. Once again, the focus is on multi-vendor VPLS/MPLS, PBB-TE and T-MPLS metro domains with an IP/MPLS core domain, demonstrating the technical interworking possibilities. Microwave backhaul equipment is a notable growth area at the interop and I’m sure I’ll return to this important topic later in the week!