Infinera unveils first platforms using its latest PIC & DSP  
Monday, December 12, 2016 at 7:02AM
Roy Rubenstein in Geoff Bennett, Infinite Capacity Engine, Lumentum, MTC-6, Telecom Infra Project, XT-3300, XT-3600, coherent DSP-ASIC, optical systems, photonic integrated circuit

Infinera has started to unveil its platform portfolio based on its Infinite Capacity Engine that combines the company's latest-generation photonic integrated circuit (PIC) and coherent DSP-ASIC technology.

 

Geoff Bennett

The first platform using the technology is the Cloud Xpress 2, Infinera second-generation data centre interconnect platform, was unveiled in September. More recently, it has added two DTN-X meshponder platforms - the XT-3300 and the XT-3600 - as well as upgrading two of its existing DTN-X platforms.

"It is impressive that Infinera has turned its Infinite Capacity Engine into products fairly quickly," says Sterling Perrin, senior analyst at Heavy Reading.

 

Cloud Express 2

The Cloud Xpress 2 uses a PIC that supports six wavelengths, each transmitting at 200 gigabits-per-second (Gbps) using polarisation-multiplexed, 16 quadrature amplitude modulation (PM-16QAM).

According to Infinera, the 1.2-terabit Cloud Xpress 2 is a 1 rack unit (1RU) box can be stacked to deliver a total of 27.6 terabits of capacity using the C-band. The platform also consumes the equivalent of 0.57W-per-gigabit, half the power consumption of the Cloud Xpress that was launched in 2014.

Infinera was the first vendor to unveil a specific product for data centre interconnect when it launched the Cloud Xpress, says Perrin. "Then everyone else came out with products that were not PIC-based, each one leapfrogging the others," he says. "So Infinera had to do something with the Cloud Xpress because it was falling behind."

Now, with the Cloud Xpress 2, Infinera is once again at the leading edge of platform performance for data centre interconnect.

Source: Gazettabyte and Daryl Inniss.

The Cloud Xpress 2 also includes integrated multiplexing and amplification. Geoff Bennett, director, solutions and technology at Infinera, points out that competitor data centre interconnect platforms that use CFP2-ACO optical modules have wavelength outputs that need to be multiplexed onto fibre whereas Infinera’s PIC has a single fibre-pair output. The platform also integrates amplification to enable a reach of up to 130km without requiring external line amplification, an important requirement for data centre operators. Using line amplification, the Cloud Xpress 2 has a reach of some 600km.

Infinera's Infinite Capacity Engine supports up to 12 wavelengths and a range of modulation schemes including PM-16QAM but the company has chosen to use six wavelengths rather than the full 12-wavelength PIC for the Cloud Xpress 2.

The Cloud Xpress 2 already delivers a 4.8x improvement in line-side capacity density compared to the Cloud Xpress, explains Bennett. The Cloud Xpress 2 supports 1.2 terabits in 1RU rack compared to 500 gigabits in the 2RU Cloud Xpress box. "That is already a big jump," says Bennett.

 

"We have to see what happens next year. Is everybody else going to come out with round-two products using conventional optics that go ahead of the Cloud Xpress 2? Or is the Infinera platform cemented in there at the leading edge?

 

There is also an economic consideration in terms of how much bandwidth the compact data centre interconnect platform delivers. Cloud Xpress 2 delivers 1.2 terabits which may not be fully used when installed, with Infinera only being paid for those wavelengths used. "There are breakeven points - granularity points - that are important with this platform," says Bennett.

A third consideration is the power consumption. "2.4 terabits [a full 12-wavelength PIC] in a rack unit will probably go way beyond what can be powered and cooled," says Bennett. "In a data centre, a key thing is the power drawn per rack unit."

Financial analyst George Notter of Jefferies visited Infinera during a recent analyst day. In a research note, he commented how Infinera has been delivering new product offerings in 4-year cycles. Notter said that while PIC development cycle times are still in the four-year range, Infinera is now working on two generations of PICs concurrently.

Infinera expects its fifth-generation PIC to be generally available in 2018. The PIC should provide up to 9.6 terabits, he says.

This suggests Infinera's next-generation Cloud Xpress could be launched in two years' time and would use the fifth-generation PIC rather than the existing Infinite Capacity Engine PIC using all 12 wavelengths.     

Perrin says that when the Cloud Xpress was first announced, he thought it proved conclusively that a PIC is best suited for data centre interconnect. But given how rapidly the industry responded with platforms based on conventional optics, he is now unsure.

"We have to see what happens next year," says Perrin. "Is everybody else going to come out with round-two products using conventional optics that go ahead of the Cloud Xpress 2? Or is the Infinera platform cemented in there at the leading edge?"

Cloud Xpress 2 is expected to be generally available early in 2017.

 

Web-scale transport

Infinera's two new DTN-X meshponder platforms, the 1.2-terabit XT-3300 and the 2.4-terabit XT-3600, are designed for longer-reach mesh networks. In effect, the two meshponder platforms have enhanced telecom capabilities compared to the Cloud Xpress 2 designed for data centre interconnect, just as Infinera launched the DTN-X XT-500 muxponder after it first launched the Cloud Xpress.

However, the XT-3300 and XT-3600 platforms reflect the growing influence of data centre traffic as part of the overall traffic carried by networks, says Infinera, such that telecom equipment need to accommodate both traffic types.

Data centre operators must cope with massive increases in capacity demand, says Bennett. Their traffic requirements are made up of single 'linear' traffic flows, each occupying the full capacity of an optical channel.

Such flows may be 10 gigabits or increasingly 100-gigabit and are typically point-to-point. "All the classical telco strategies for dealing with over-demand don't work in such web-scale networks because they have 'elephant' flows that can't be broken up," says Bennett. 

 

How do you allow telcos to take on cloud architectures but still solve telco problems? And how do you allow web-scale data centre operators to scale out to a network that is telco-grade?

 

In contrast, telcos must support combinations of many, smaller traffic flows from hundreds or thousands of locations. But as operators start to re-engineer their networks to support technologies such as network function virtualisation and cloud services, they increasingly face the same challenges the data centre operators face, says Infinera.

"This is the nub of the problem in how the intelligent transport layer must evolve to be cloud-scale," says Bennett. "How do you allow telcos to take on cloud architectures but still solve telco problems? And how do you allow web-scale data centre operators to scale out to a network that is telco-grade?"

 

Meshponders

Infinera's XT-3300 is styled on the Cloud Xpress 2. It is a stackable 1.2-terabit line-side 1 rack-unit box that is telco grade: it is NEBS-compliant and is designed to work on a dense WDM open line system. The XT-3300 has a dozen 100 Gigabit Ethernet client side ports and like the Cloud Xpress 2, six wavelengths are used to deliver a total of 1.2 terabits of line-side capacity.

"The XT-3300 is more of a data centre product," says Bennett. "With the Cloud Xpress, we tend to operate over fairly short distances; the XT-3300 is a souped-up version of that."

In contrast, the XT-3600, at 4RU, is four times the height of the XT 3300, and at 2.4 terabits supports double the line side capacity by using 12 wavelengths. The platform also supports electronic switching and multiplexing.

Both meshponders supports all the advanced coherent toolkit features that Infinera detailed at the start of the year such as sub-carriers, gain sharing and matrix-enhanced phase-shift keying for long-haul links. Both platforms have a maximum reach of 6,000km.

The XT-3600 works with two existing Infinera DTN-X platforms - the XTC-4 and the XTC-10. Accordingly, these platforms have been given a mid-life upgrade with new Infinite Capacity Engine line cards and higher capacity OTN switching to accommodate the traffic from the faster line cards. The XTC-4's OTN switching capacity has been upgraded to 4.8 terabits, while the XTC-10 OTN switching capacity is upgraded to 12 terabits.    

The two XT platforms are dubbed meshponders. With a traditional muxponder, multiple client signals are aggregated before being sent out on a higher capacity single optical channel. A meshponder extends the concept by allowing multiple client signals sent on optical channels that are sent to multiple destinations (see diagrams).

The muxponder is made possible because Infinera's PIC is 'sliceable', the wavelengths supported by the PIC can be used in different optical channel combinations - single channel and super-channels - such that ROADMs within the network can split the optical channels and route them to their destinations.

"The PIC has been redesigned to allow it to be sliced," says Bennett. To do this, guard bands are added each side of a channel. As such, a sliceable channel is less spectrally efficient than a super-channel whose constituent wavelengths are packed more closely together as all are sent to one destination.   

The line side capacity, either a sliced super-channel or a single super-channel, can be terminated on one of Infinera's core boxes such as the XTC-4 or XTC-10.

Heavy Reading’s Perrin views the meshponders products as an incremental announcement: using its latest PIC, users now have the ability to go point to multipoint using a network of Infinera's XT systems. The latest XT platforms will appeal to web-scale companies that have metro reaches or greater, says Perrin: "Infinera has got wholesale providers in Europe that transport big chunks of traffic across a greater distance than the Cloud Xpress 2 can do."

 

Infinera expects its fifth-generation PIC to be generally available in 2018. The PIC should provide up to 9.6 terabits

 

Flexible-grid open line systems 

Infinera has also announced the MTC-6 flexible grid open line system platform. Infinera's current FlexILS line system is the 9-slot MTC-9. "The FlexILS is the industry's most widely deployed flex-grid line system," says Bennett.

Infinera has also been working with Lumentum to demonstrate its platforms working with Lumentum's white box open line system.  "We have a lot of experience working with open line systems," says Bennett. Infinera and Lumentum are also part of the open packet optical transport, part of the Telecom Infra Project (TIP) industry initiative co-founded by Facebook, Deutsche Telecom and SK Telecom.

The MTC-6 flexible open line system occupies 6 slots and uses the same cards as its larger counterpart MTC-9. These boards include FlexROADM cards, EDFA amplifiers, RAMAN amplifiers and gain flatteners. The MTC-6 supports the C and L bands, effectively doubling overall transmission capacity from 25.6 terabits using Infinera's platforms in the C-band to 51.2 terabits using both bands. 

Infinera says three of the top four US internet content providers are using its platforms. "We are in the privileged position of the network architects in those companies telling us what they want," says Bennett.

The MTC-6 FlexILS open line system is available now. The XT-3300 will be available in the first quarter of 2017 with the remaining platforms scheduled for the second quarter of 2017. 

Article originally appeared on Gazettabyte (http://www.gazettabyte.com/).
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