Paying homage to Harald Bock
Harald Bock, described by an optical networking executive as one of the great people of our industry, has died. Former colleagues describe the man and their sense of loss
Those who knew and worked with Harald Bock have been stunned by his sudden passing at 55. For them, Harald was a valued and much-admired friend, a deep thinker who made his views heard, quietly yet powerfully.
Last February, Harald changed jobs, becoming chief product officer at Ekinops after six years at Infinera. He was excited by the role and enjoyed his introductory period travelling to Ekinops’ sites, meeting colleagues and customers, and working on the company’s strategy.
Sylvain Quartier, Ekinops’ chief marketing & strategy officer, says it took the company a year to find the right candidate. Ekinops knew of Harald’s optical networking expertise but was impressed with his keenness to expand into what, for him, were new product areas such as routeing and cybersecurity.
“We needed someone expert in one domain and with good experience in product strategy,” says Quartier. “He was full of joy and happy to work.”
During Harald’s short spell at the company, he sharpened Ekinops’s product plans. “We’re executing his roadmap and strategy today,” says Quartier. “In six months, he had a great impact.”
Career
Harald earned his PhD in physics, specialising in polymer materials.
“Polymers may become an important material system for future high-speed [optical] modulators,” says Uwe Fischer, who was chief technology officer (CTO) at former optical networking firm, Coriant. “He was ahead of his time by doing something in his PhD thesis which is about to become important in business and technology.”
Harald’s career spanned some notable optical networking firms: Marconi, Nokia Siemens Networks, Coriant, and Infinera. He was part of Uwe Fischer’s team at Nokia Siemens Networks and Coriant. Harald’s strength was as a technologist, and had roles in several CTO offices.
Stefan Voll, then a lead product line manager and now senior director of business development at Adtran, worked with Harald at Nokia Siemens Networks in 2012.
The two were tasked with carving out the optical business of Nokia Siemens Networks in what was to become Coriant. “The carve-out was a big achievement,” says Voll. Harald represented the CTO office and Voll led the product line manager team and the two were tasked with making the product portfolio not only viable but profitable. This required aligning technical aspects with business needs, setting the foundation for Coriant’s operations.
At Coriant, Harald contributed to the development of Groove, one of the first compact modular platform for metro wavelength division multiplexing (WDM) and long-haul networks. Harald continued in the CTO office at Infinera after it acquired Coriant in 2019.
More recently, Harald served as editor of the Optical Internetworking Forum’s (OIF) 1600ZR project, taking over the role after an OIF member stepped down. The work involves standardising 1600-gigabit coherent optics for high-capacity networks. “He stepped in as smooth as possible,” says Karl Gass, optical vice chair of the OIF’s physical link layer (PLL) working group. “He knew how to manage personalities and get things done.”
Work ethic
Christian Uremovic, senior director of solution marketing at Nokia Optical Networks, worked with Harald at Coriant and Infinera. “He was a respected and valued technology guide for product line management and sales and for us in marketing,” says Uremovic. It wasn’t always an easy role; groups in the company would pull in different directions, and bringing it all together was a challenge. “Sometimes you had to make difficult decisions,” says Uremovic.
“He would like to understand basic technologies, and when, at executive meetings, he wanted to bring his opinion and convince others, he would talk quietly,” says Ekinop’s Quartier. “Everybody would be quiet because you wanted to hear him, and he made a strong impression.” With this quiet manner, Harald would progress the discussion and bring everybody in the right direction, says Quartier.
It is something Robert Richter, managing director and senior vice president, customer executive, product marketing office, at Nokia, highlights: “Harald would reiterate his view calmly, even if it annoyed some leaders, but it was always positive,” he says, adding that Harald was not the kind of guy who did what management told him. But he was always trying to change opinions constructively.
Voll reinforces this, saying Harald would not let shortcuts slide, ensuring all critical aspects were covered. “He was not afraid of conflict.” Harald would broaden discussions to bring in new angles to the point where it could be annoying. “But it was always valuable,” says Voll. “He was not fast, and that’s because he was a deep thinker. He reacted in meetings, but not immediately; he needed some time putting his thoughts together.”
Voll says Harald was focused on long-term technology trends, five to six years out, compared to product line managers’ shorter-term view. “He taught me to assess competitiveness through metrics like capacity per power consumption,” says Voll. Harald would say: “Convert it into capacity per volume or per power consumption.” Ten years ago, these were not usual metrics, but Harald used them to measure product plans. Harald would also also look product optimisations, such as whether a platform’s chips had features that were not used.
Maxim Kuschnerov, Director of R&D, at Huawei, worked with Harald at Coriant. He recalls a meeting he had with Deutsche Telekom presenting Huawei’s research topics. Afterwards, a Deutsche Telekom executive remarked that although it was framed as a research discussion, Kuschnerov kept steering the conversation toward commercial applications and customer value: “It reminds me of a guy at Coriant who talks about use cases a lot — Harald Bock”. Smiling, Kuschnerov replied: “Where do you think I was taught to think like that? I worked with Harald!”
Traits
Ekinops’ Quartier highlights Harald’s general cheerfulness: “He was always smiling, which was much appreciated.”
Richter, who worked with Harald for 18 years at Nokia Siemens Networks and Coriant, describes him as the most empathetic person he has met. “He was always listening to people and was very patient,” he says. Harald would bring cakes to the office from vacations and would never speak ill of others. He’d keep positive even during challenging times and in that sense, he was a role model, says Richter: “It was always a pleasure to talk to him over a coffee. He was open to a dialogue.”
Harald had an impressive fitness routine. “He’d bike 20km, swim for an hour, then come to the office relaxed,” says Voll. Until recently, Fischer and Harald would go biking on 40-kilometre rides. “Sometimes he was behind in my slipstream, then we change positions,” says Fischer. “We were proud of the competitive speed and times we could achieve together.” He was a keen water polo player in his youth.
Fluent in English, French, and his native German, Harald read books in all three languages. He adored France – his wife is French – with its pastries and Brittany with its Hydrangeas. He said how the Hydrangeas in his garden struggled, yet on seeing the flourishing bands of colour in Brittany (pictured), he was determined to try again.
Legacy
When colleagues talk about Harald, they recount his warmth and character.
Uremovic recollects sharing an office and hearing Harald’s diplomatic charm on calls. These experiences have shaped his ability to connect better with others. He will also miss their talks: “To me, he was like a big brother.”
Harald made a deep impression during his short time at Ekinops. “We miss him,” says Quartier. “We will always have his memory at Ekinops.”
Fischer highlights their shared interests in life – sport and a love of France.”There was a lot of mutual understanding which we didn’t need to put into words,” says Fischer. “Sometimes, when you feel close to somebody, you don’t even need to talk.”
Fischer, who has watched Harald’s career over the years, laments a life cut short. “He was at the peak of his career,” he says. ”He brought to Ekinops all his experience of the last 20 to 30 years so this period was maybe the most impactful time of his life.”
Richter’s grief over his lost colleague is evident in his sombre tone and demeanour, perhaps the deepest tribute one can pay to someone held so dear.
Books of 2024: Part 1
Gazettabyte asks industry figures to pick their notable reads during the year. Harald Bock, Jonathan Homa, and Maxim Kuschenrov kick off with their chosen books.
Harald Bock, Vice President Network Architecture, Infinera
I love reading but have not read as many books as I would have liked in recent years. I decided to change that in 2024.
My pick of fictional books this year was mainly classic science fiction after seeing the movie Dune Part 2 with my family. I read the book Dune by Frank Herbert, published in 1965, a while ago, and I wasn’t sure that the movies did the book justice.
My son advised me to launch myself into all five sequels of Dune, which kept me busy. While the sequels are for die-hard fans, I recommend the first of the books whether or not you’ve seen the movie. Frank Herbert’s modern and sophisticated thinking adds unconventional perspectives to up-to-date societal, environmental and political questions.
I went on to read Ray Bradbury’s The Martian Chronicles and H.G. Wells’ Time Machine, published in 1950 and 1895, respectively. The two books are fascinating as they are timeless and do not require any adaptation to modern times. They are classics of their genre.
I also found time for non-fictional books. I was looking for unconventional thoughts by unlikely authors to challenge my thinking.
One that adds to the discussions about sustainability is a book by Fred Vargas, a French author who normally writes crime fiction and is an archaeologist and historian. ‘L’humanité en péril: Virons de bord, toute !‘ was published as a follow-up to an older, shorter text by the same author read on the occasion of the conference on climate change COP24 in Paris in 2018. Surprisingly, the book does not yet exist in English.
Another interesting author is a professor of computer science, Katharina Zweig. Her books: Awkward Intelligence: Where AI Goes Wrong, Why It Matters, and What We Can Do about It and Die KI war’s: Von absurd bis tödlich: Die Tücken der künstlichen Intelligenz (‘It was the AI: From absurd to deadly: The pitfalls of artificial intelligence’, in German only to date) do a good job exploring considerations, boundary conditions, and limits of using AI systems in practical decision-making.
Jonathan Homa, Senior Director of Solutions Marketing at Ribbon Communications
I recommend a book I re-read this year: The Name of the Rose by Umberto Eco. As my wife points out, re-reading a book is its own recommendation.
This is an intricate and beautifully written murder mystery novel set in late medieval Europe. Through the eyes of the protagonist, Brother William of Baskerville, we begin to see glimpses of enlightenment. I also recommend the 1986 movie by the same name, starring Sean Connery.
Maxim Kuschnerov, director of R&D at Huawei
I had a light year of reading. One book I did read was Nuclear War: A Scenario by Annie Jacobsen which details the scenario of how a nuclear war would go down if someone started it. The answer: a surprisingly quick annihilation of humankind.
I also read Angela Merkel’s autobiography, Freedom: Memoirs 1954 – 2021 – that was published recently. I was hoping for more insight into her thinking when dealing with the immigration crisis or with Vladimir Putin, but the book added nothing that I didn’t already know about her. The book clarified how Angela Merkel was profoundly shaped in her upbringing by Eastern German communism and Russia.
The request to highlight my reads of 2024 made me think about what I have been reading this past year. Perhaps disappointingly, it turned out to be mostly not-noteworthy fiction.
OFC 2024 industry reflections: Final part
Chris Cole, Consultant
OFC and optics were back with a vengeance. The high level of excitement and participation in the technical and exhibit programmes was fueled by artifical intelligence/ machine learning (AI/ML). To moderate this exuberance, a few reality checks are offered.
During the Optica Executive Forum, held on the Monday, one of the panels was with optics industry CEOs. They were asked if AI/ML is a bubble. All five said no. They are right that there is a real, dramatic increase in optics demand driven by AI/ML, with solid projections showing exponential growth.
At the same time, it is a bubble because of the outrageous valuations for anything with an AI/ML label, even on the most mundane products. Many booths in the Exhibit Hall had AI/ML on their panels, for the same product types companies have been showing for years. Some of the start-ups and public companies presenting and exhibiting at OFC have frothy valuations by claiming to solve compute bottlenecks. An example is optically interconnecting memory, which sends investors into a frenzy, as if this has not been considered for decades.
The problem with a bubble is that it misallocates resources to promises of near-term pay off, at the expense of investment into long-term fundamental technology which is the only way to enable a paradigm shift to optical AI/ML interconnect.
I presented a version of the below table at the OFC Executive Forum, pointing out that there have only been two paradigm shifts in optical datacom, and these were enabled by fundamentally new optical components and devices which took decades to develop.
My advice to investors was to be skeptical of any optically-enabled breakthrough claims which simply rearrange or integrate existing components and devices. As with previous bubbles, this one will self-correct, and many of the stratospheric valuations will collapse.
Source: Chris Cole
A second dose of reality was provided by Ashkan Seyedi of Nvidia, in several OFC forums, illustrated by the Today’s Interconnect Details table below (shared with permission).
Source: Ashkan Seyedi, Nvidia
He pointed out that the dominant AI/ML interconnect continues to be copper because it beats optics by integer or decade better metrics of bandwidth density, power, and cost. Existing data centre optical networking technology cannot simply be repackaged as optical compute input-output (I/O), including optical memory interconnect, because that does not beat copper.
A third dose of reality came from Xiang Zhou of Google and Qing Wang of Meta in separate detailed analysis presented at the Future of LPO (Linear Pluggable Optics) Workshop. They showed that not only does linear pluggable optics have no future beyond 112 gigabits per lane, but even at that rate it is highly constrained, making it unsuitable for general data centre deployment.
Yet linear pluggable optics was one of the big stories at OFC 2024, with many highly favourable presentations and more than two dozen booths exhibiting it in some form. This was the culmination of a view that has been advanced for years that optics development is too slow, especially if it involves standards. LPO was moved blazingly fast into prototype hardware without being preceded by extensive analysis. The result was predictable as testing in typical large deployment scenarios found significant problems.
At OFC 2025, there will be few if any linear pluggable optics demos. And it will not be generally deployed in large data centres.
Coincidently, the OIF announced that it started a project to standardise optics with one digital signal processor (DSP) in the link, located in the transmitter. This was preceded by analysis, including by Google and Meta, showing good margin against the types of impairments found in large data centres. The expectation is that many IC vendors will have DSP on transmit-only chips soon, including likely at OFC 2025.
A saving grace of linear pluggable optics may be the leveraging of related OIF work on linear receiver specification methodology. Another benefit may be the reaffirmation that real progress in optics is hard and requires fundamental understanding. Shortcutting of well-established engineering practices leads to wasted effort.
Real advances require large investment and take many years, which is what is necessary for optical AI/ML compute interconnect. Let’s hope investors realise this.
Hojjat Salemi, Chief Business Development Officer, Ranovus
Hyperscalers are increasingly recognising that scaling AI/ML compute demands extensive optical connectivity, and the conventional approach of using pluggable optical modules is proving inadequate.
The network infrastructure plays a pivotal role in the compute architecture, with various optimisation strategies depending on the workload. Both compute scale-up and scale-out scenarios necessitate substantial connectivity, high-density beach-front, cost-effectiveness, and energy efficiency. These requirements underscore the advantages of co-packaged optics (CPO) in meeting the evolving demands of AI/ML compute scaling.
It is great to see prominent tier-1 vendors like Nvidia, AMD, Broadcom, Marvell, GlobalFoundries, and TSMC embracing co-packaged optics. Their endorsement shows a significant step forward, indicating that the supply chain is gearing up for high-volume manufacturing by 2026. The substantial investments being poured into this technology underscore the collective effort to address the pressing challenge of scaling compute efficiently. This momentum bodes well for the future of AI/ML compute infrastructure and its ability to meet the escalating demands of various applications.
What surprise me was how fast low-power pluggable optics fizzled. While initially shown as a great technology, linear pluggable optics ultimately fell short in meeting some critical requirements crucial to Hyperscalers. Although retimed pluggable optical modules have been effective in certain applications and are likely to continue serving those needs for the foreseeable future, the evolving demands of new applications such as scaling compute necessitate innovative solutions like co-packaged optics.
The shift towards co-packaged optics highlights the importance of adapting to emerging technologies that can better address the unique challenges and requirements of rapidly evolving industries like hyperscale computing.
Harald Bock, Vice President Network Architecture, Infinera
I am impressed by the range of topics, excellent scientific work and product innovation each time I attend OFC.
Normally, the show's takeaways differ among the participants that I talk to. This year, most of the attendees I chatted agreed on the main topics. The memorable items this year ranged from artificial intelligence (AI) data centres, 800 gigabit-per-second (Gbps) pluggables, to the Full Spectrum Concert at Infinera’s OFC party that was held on the USS Midway.
AI is becoming the key driver for network capacity. While we are a very technology-driven industry, the interest in different technologies is driven by the business opportunities we expect. This puts AI at the top of the list. It is not the AI use cases in network operations, planning, and analytics, which are all progressing, but rather the impact that deploying AI data centres will have on network capacity and particularly on optical interfaces within and between data centres.
The interest was clearly amplified by the fact that recovery of the telecom networks business is only expected in the year’s second half.
Short term, AI infrastructure creates massive demand for short-reach interconnect within data centres, with longer-reach inter-data centre connectivity also being driven by new buildouts. So, we can expect AI to be the key driver of network bandwidth in the coming years.
It is in this context that linear pluggable optics has become an important candidate technology to provide efficient, low-energy interconnect, and as a result, it generated a huge amount of interest this year, stealing some of the attention that co-packaged optics or similar approaches have received in the past. Overall, AI use cases drove huge interest in 800Gbps pluggable optics products and demonstrations at the show.
Reducing interface and network power consumption have become key industry objectives. In all of these use cases and products, power consumption is now the main optimisation goal in order to drive down overall data centre power or to fit all pluggable optics into the same existing form factors (QSFP-DD and OSFP), even at higher rates such as 1.6Tbps.
I do believe that reducing power consumption, be it per capacity, or per reach x capacity depending on use case, has become our industry’s main objective. Looking at projected capacity growth that will continue at 35 to 40 per cent per year across much of cloud networks, that is what we all should be working on.
Another observation is that power consumption and capacity per duct have replaced spectral efficiency as the figure of merit. You could say that this is starting to replace the objective of increasing fibre capacity that our industry has been working under for many years.
We have all discussed the fact that we are no longer going to be able to easily increase spectral efficiency as we are approaching Shannon’s limit. In order to further increase fibre capacity, we have been talking about additional wavelength bands, with products now achieving beyond 10-terabit transmission bandwidth with Super C- and Super L-band and the option to add the S-, O-, and U- bands, as well as about spatial division multiplexing, which today refers to the use of multiple fibre cores to transmit data.
Before OFC, I was puzzled about the steps we, as an industry, would take since all of these require more than a single product from one company. Indeed it is an ecosystem of related components, amplifiers, wavelength handling, even splicing procedures. After OFC, I am now confident that uncoupled multi-core fibre is a good candidate for a next step, with progress on additional wavelength bands not at all out of the picture.
There is one additional point I learned from looking at this topic. In real-world deployments today, multi-core fibre will accelerate a massive increase in parallel fibres that are being deployed in fibre ducts across the world. To me, that means that while we are going to all focus on power consumption as a key measure for innovation, we should really use capacity per duct as an additional figure of merit.
In terms of technological progress, I would like to call out the area of quantum photonics.
We all saw the results from an impressive research push in this area, with complex photonic integration and interesting use cases being explored. The amount of work done in this area makes it difficult for me to keep up to speed. I continue to be fascinated and excited about the work done.
An entirely different category of innovation was shown in the post-deadline session where Microsoft and University of Southampton presented hollow-core fiber with a record 0.11 dB/km fiber loss. While we have been talking about the great promise of anti-resonant hollow-core fiber for a while as it offers significantly reduced latency, it reduces signal distortion by removing nonlinearity and offering low dispersion. All that has been shown before, but achieving a fibre loss that is considerably lower than that of all other fibre types is excellent news.
It confirms that hollow-core fiber could change the systems and the networks we build, and I will continue to keep close tabs on the progress in this area.
Overall, OFC 2024 was a great show, with my company launching new products and having a packed booth full of visitors, a large number of customer engagements, and meetings with most of our suppliers.
I left San Diego already looking forward to next year's OFC.