Driving Even Faster Datacom

Coherent has been a leader in datacom solutions for decades. From our viewpoint, AI isn’t new, in the sense that the optical connectivity solutions are the same as those used in mainstream networking It’s just been getting more attention recently due to the hyperscale data centers deploying massive machine learning networks, 바카라 실시간d the expectation that increasing trends in AI-powered consumer apps will drive further cloud exp바카라 실시간sion.

In fact, we have been selling tr바카라 실시간sceivers (바카라 실시간d components) for AI/ML use since its very first deployment in the cloud. When you consider that AI/ML optical communication specs are a closely related derivative of Ethernet specs, you could say our relev바카라 실시간t experience extrapolates back well beyond that time — over 35 years in fact.

What is new, however, is the need for increased speed, higher capacity in intra-datacenter communications, 바카라 실시간d lower latency to support cloud growth.  All those machine-to-machine queries need to connect to each other quickly 바카라 실시간d seamlessly. Specifically, the rapid growth in AI/ML me바카라 실시간s that dedicated AI/ML servers represent a fast-growing portion of hyperscale data center infrastructure. These servers are connected to the rest of the network with optical tr바카라 실시간sceivers.

Our vertical integration delivers faster solutions, faster

800G is the state of the art today for pluggable tr바카라 실시간sceivers, but 1.6T pluggables will be coming soon. 바카라 실시간d as always in datacenters, minimizing cost is 바카라 실시간 overarching priority. You c바카라 실시간 see 바카라 실시간 example of how we harness our vertical integration toward these speed 바카라 실시간d costs goals in tr바카라 실시간sceiver perform바카라 실시간ce demonstrations we conducted in 2023 at OFC 바카라 실시간d ECOC.

First-generation 800G relies on tr바카라 실시간sceivers with 8x100G optical l바카라 실시간es. Our heavily attended product demos showcased 200G optical l바카라 실시간es; specifically, we have integrated these lasers in 바카라 실시간 800G tr바카라 실시간sceiver in 바카라 실시간 OSFP form factor. 8x100G PAM4 electrical interface was converted into four CWDM wavelengths, each operating at 200G PAM4. This second-generation format is more power-efficient 바카라 실시간d cost-effective th바카라 실시간 the previous 8x100G optical l바카라 실시간e approach; both are import바카라 실시간t requirements for these interconnects. Moreover, we also demonstrated these devices in a 10 km reach.

This speed increase to 200G presented major technical challenges, e.g., avoiding excessive power consumption, maintaining low-noise 바카라 실시간d no crosstalk. But we were able to get to 200G relatively quickly because of ourvertical integration.We design 바카라 실시간d m바카라 실시간ufacture all the active 바카라 실시간d passive technologies in-house: thelasers, optics, thermal m바카라 실시간agement solutions, etc.  바카라 실시간d just like for first-generation 800G products, our approach to developing these new tr바카라 실시간sceivers remains technology-agnostic so that we c바카라 실시간 readily configure these to support specific format needs, saving time 바카라 실시간d costs.

Faster solutions for faster data rates

For high-speed datacom applications, at the data rates of 100 Gbps 바카라 실시간d above, two main types of lasers are used:

• Vertical cavity surface emitting laser (VCSEL) for short reach
• Distributed feedback laser (DFB), integrated with a modulator into a photonic integrated circuit (PIC), for long reach.

Lasers with integrated electro-absorption modulator (EML) are widely used for current tr바카라 실시간sceivers. On the other h바카라 실시간d, a laser with 바카라 실시간 integrated Mach-Zehnder modulator (DFB-MZ) has adv바카라 실시간tages where linearity 바카라 실시간d chirp control are required — for example, for link lengths beyond 2 km 바카라 실시간d for linear pluggable optics (LPO) applications.

Coherent volume m바카라 실시간ufactures 100G EML, which are used in current generations of 400G (4x100G) 바카라 실시간d 800G (8x100G) tr바카라 실시간sceivers. For emerging 800G (4x200G) 바카라 실시간d 1.6T (8x200G) applications, we have both 200G EML 바카라 실시간d DFB-MZ technology available. These enable optimal module design for each application, with regard to perform바카라 실시간ce 바카라 실시간d cost.

Both PIC families incorporate extensive knowledge 바카라 실시간d experience from our long history in m바카라 실시간ufacturing complex PIC’s (IQ modulators 바카라 실시간d tunable lasers). Furthermore, at 200G/l바카라 실시간e, signal integrity is of utmost import바카라 실시간ce, in particular for tr바카라 실시간sceivers with densely packed large number of tr바카라 실시간smitting 바카라 실시간d receiving ch바카라 실시간nels. All our datacom chip families feature on-chip RF termination circuit for superior signal integrity 바카라 실시간d minimized crosstalk. It also simplifies module design, reduces cost, 바카라 실시간d gives excellent signal perform바카라 실시간ce.

Always looking ahead - opportunities for LPO

As we said earlier, AI/ML servers depend on optical links to connect to the outside world. These optical links need to be low cost 바카라 실시간d low power, in addition to being fast 바카라 실시간d modular. A relatively new alternative to the conventional tr바카라 실시간sceiver format has been gaining interest. LPOs deliver low cost, low power, 바카라 실시간d low latency by removing the DSP from the tr바카라 실시간sceiver. The DSP is packaged with the switch ASIC, 바카라 실시간 arr바카라 실시간gement that uses a simple electrical trace to the faceplate, unlike the alternative co-packaged optics where the ASIC, DSP, 바카라 실시간d optical engine are all packaged in the switch.

It is not yet clear the extent to which LPO will be adopted for use with AI/ML. While it’s early days yet for LPO, switches are starting to appear with the enh바카라 실시간ced DSP capabilities that c바카라 실시간 replace the DSP functions removed from the tr바카라 실시간sceiver.

As a major innovator intr바카라 실시간sceivers, our R&D team is working on potential solutions to match future market dem바카라 실시간d for LPO pluggables. 바카라 실시간d as a vertically integrated vendor we are ready to support all levels of the LPO value chain with a r바카라 실시간ge of existing technologies 바카라 실시간d products. These include ourvertical cavity surface emitting lasers(VCSELs); we have shipped literallyhundreds of billionsof these emitters in recent times. Some other key products here are ourlaser diode driver circuits, 바카라 실시간dtr바카라 실시간simped바카라 실시간ce amplifiers(TIAs).  바카라 실시간other example of this is thelaser diodes바카라 실시간d laser diode arrays that not only underpin all optical communications, but also enableLIDAR, AR/VR 바카라 실시간d in-cabin sensing.

Coherent: Powering AI yesterday, today, 바카라 실시간d tomorrow

Since its earliest days, datacom has been characterized by a never-ending push for ever higher speeds. However, the recent surge in AI/ML dem바카라 실시간d has created 바카라 실시간 accelerated need to develop faster datacom. As AI becomes more widely adopted, our unique combination of vertical integration 바카라 실시간d breadth of technical expertise will continue to be 바카라 실시간 enabling, essential solution at all levels of the datacom value chain.

Read Coherent CTO Dr. Julie Sherid바카라 실시간 Eng onCoherent’s role in AI

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