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Oclaro uses Acacia’s Meru DSP for its CFP2-DCO 

Oclaro will use Acacia Communications’ coherent DSP for its pluggable CFP2 Digital Coherent Optics (CFP2-DCO) module. The module will be compatible with Acacia’s own CFP2-DCO, effectively offering customers a second source. 

Tom Williams This is the first time Acacia is making its coherent DSP technology available to a fellow module maker, says Tom Williams, Acacia’s senior director, marketing.

Acacia benefits from the deal by expanding the market for its technology, while Oclaro gains access to a leading low-power coherent DSP, the Meru, and can bring to market its own CFP2-DCO product. 

Williams says the move was encouraged by customers and that having a second source and achieving interoperability will drive CFP2-DCO market adoption. That said, Acacia is not looking for further module partners. “With two strong suppliers, we don’t see a need to add additional ones,” says Williams.  

“This agreement is a sign that the market is reaching maturity, with suppliers transitioning from grabbing market share at all costs to more rational strategies,” says Vladimir Kozlov, CEO and founder of LightCounting Market Research.



The CFP2-DCO is a dense wavelength-division multiplexing module that supports 100-gigabit and 200-gigabit data rates.

With the CFP2-DCO design, the coherent DSP sits within the module, unlike the CFP2 Analog Coherent Optics (CFP2-ACO) where the DSP chip is external, residing on the line card. 

According to Kevin Affolter, Oclaro’s vice president strategic marketing, the company looked at several merchant and non-merchant coherent DSPs but chose the Meru due to its low power consumption and its support for 200 gigabits using 8-ary quadrature amplitude modulation (8-QAM) as well as the 16-QAM scheme. Using 8-QAM extends the optical reach of 200-gigabit wavelengths.


This agreement is a sign that the market is reaching maturity, with suppliers transitioning from grabbing market share at all costs to more rational strategies


At 100 gigabits the CFP2-DCO achieves long-haul distances of 2,000km whereas at 200 gigabit at 8-QAM, the reach is in excess of 1,000km. The 8-QAM requires a wider passband than the 16-QAM, however, such that in certain metro networks where the signal passes through several ROADM stages, it is better to use the 16-QAM mode, says Acacia.


Source: Acacia, Gazettabyte

Oclaro’s design will combine the Meru with its indium phosphide-based optics whereas Acacia’s CFP2-DCO uses silicon photonics technology. The power consumption of the CFP2-DCO module is of the order of 20W.

The two companies say their CFP2-DCO modules will be compatible with the multi-source agreement for open reconfigurable add-drop multiplexers (ROADMs). The Open ROADM MSA is backed by 16 companies, eight of which are operators. The standard currently only defines 100-gigabit transmission based on a hard-decision forward-error correction. 

“There are several carriers, AT&T being the most prominent, within Open ROADM,” says Affolter. “It makes sense for both companies to make sure the needs of Open ROADM are addressed.” 


Coherent shift 

In 2017, Oclaro was one of three optical module companies that signed an agreement with Ciena to use the systems vendor’s WaveLogic Ai coherent DSP to develop a 400-gigabit transponder.    

Kevin Affolter

Affolter says the Ciena and Acacia agreements should be seen as distinct; the 400-gigabit design is a large, 5x7-inch non-pluggable module designed for maximum reach and capacity. “The deals are complementary and this announcement has no impact on the Ciena announcement,” says Affolter.

Does the offering of proprietary DSPs to module makers suggest a shift in coherent that has always been seen as a strategic technology that allows for differentiation? 

Affolter thinks not. “There are several vertically integrated vendors with their own DSPs that will continue to leverage their investment as much as they can,” he says. “But there is also an evolution of end customers and network equipment manufacturers that are moving to more pluggable solutions and that is where the -DCO really plays.”          

Oclaro expects to have first samples of its CFP2-DCO by year-end. Meanwhile, Acacia’s CFP2-DCO has been generally available for over six months.

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