ECOC 2013 review - Part 1
Thursday, October 10, 2013 at 9:19AM Gazettabyte surveys some of the notable product announcements made at the recent European Conference on Optical Communication (ECOC) held in London.
Part 1: Highlights
- First CFP4 module demonstration from Finisar
- Acacia Communications unveils first 100 Gig coherent CFP
- Oplink announces a 100 Gig direct detection CFP
- Second-generation coherent components take shape
100 Gigabit pluggables
Finisar used the ECOC exhibition to demonstrate the first CFP4 optical module, the smallest of the CFP MSA family of modules. The first CFP4 supports the 100GBASE-SR4 standard comprising four electrical and four optical channels, each at 25 Gigabit-per-second (Gbps).
The CFP4 is a quarter of the width of the CFP while the CFP2 is about a half the CFP's width. The CFP4 thus promises to quadruple the faceplate port density compared to using the CFP. Finisar says the CFP4 does even better, supporting line cards with 3.6 Terabits of capacity.
"It is not just the [CFP4's] width but the length and height that are shorter," says Rafik Ward, vice president of marketing at Finisar. The CFP4s can be aligned in two columns - belly-to-belly - on the card, achieving 3.6Tbps, each row comprising 18 CFP4 modules.
We see the CFP4 as a necessity to continue to grow the 100 Gigabit Ethernet market
The CFP4 was always scheduled to follow quickly the launch of the CFP2, says Ward. But the availability of the CFP4 will be important for the MSA. Data centre switch vendor Arista Networks has said that the CFP2 was late to market, while Cisco Systems has developed the CPAK, its own CFP2 alternative. "We see it [the CFP4] as a necessity to continue to grow the 100 Gigabit Ethernet market," says Ward.
Other 100 Gigabit Ethernet (GbE) variants will follow in the CFP4 form factor such as the LR4 and SR10 and the 10x10GbE breakout variant. This raises the interesting prospect of requiring an “inverse gearbox” chip that will translate between the CFP4's four electrical channels and the SR10's 10 optical channels. "We are going to see a lot of design activity around CFP4 in 2014," says Ward.
Meanwhile, Acacia Communications unveiled the AC-100, the first 100 Gig coherent CFP module for metro and regional networks, that includes a digital signal processor (DSP) system-on-chip.
"The DSP can be programmed for different performance and power levels to achieve a range of distances," says Daryl Inniss, vice president and practice leader components at market research firm, Ovum.
Acacia Communications says a CFP-based coherent design provides carriers and content providers with a 100 Gig metro solution that is more economical than 10 Gig.
Oplink Communications announced a direct detection 100 Gig metro CFP at ECOC. The 4x28Gbps CFP uses MultiPhy's maximum likelihood sequence estimation (MLSE) algorithm implemented using its MP1100Q and MP1101Q ICs. The devices enhance the reach of the module and allows 10 Gig optical components to be used for the receive and transmit paths. "Oplink’s CFP is the first module to come to market with our devices inside," says Neal Neslusan, vice president of marketing and sales at MultiPhy.
There are now at least three vendors selling direct-detection 100Gbps modules, says Neslusan, with Oplink and Menara Networks, which has also announced a CFP product, joining Finisar.
MultiPhy is working with several additional companies and that one system vendor will come to market with a product using the company's chips in the coming months. The company is also working on a second-generation direct detection IC design. "We believe there is a compelling roadmap story for direct detection," says Neslusan.
Oclaro announced it is now shipping in volume its 10km 100GBASE-LR4 CFP2 supporting 100GbE and OTU4 (OTN) rates. Oclaro has demonstrated the CFP2 working with a Xilinx Virtex 7 FPGA. "If customers choose that combination of technology, we have already tested it for them and they can rely on those rates [100GbE and OTU4] working," says Per Hansen, vice president of product marketing, optical networks solutions at Oclaro.
JDSU also said that its CFP2 LR4 is nearing completion. "We are getting pretty close to releasing it," says Brandon Collings, chief technology officer, communications and commercial optical products at JDSU.
Ed Murphy, JDSU
The integrated transmit and receive optical sub-assembly (TOSA/ ROSA) designs for the CFP2 LR4 use hybrid integration.
"In this case it is not monolithic integration as it is in the case of the indium phosphide line side modules but hybrid integration taking advantage of our PLC (planar lightwave circuit) technology in combination with arrays of photo detectors or high speed EMLs (externally modulated lasers)," says Murphy.
JDSU has based its module roadmap on the CFP2 TOSA and ROSA designs. The designs are sufficiently integrated to also fit within the QSFP28 and CFP4 modules.
There may be tweaks to the chips to lower the power dissipation, says Murphy, but these will be minor variants on existing parts.
Coherent components
Several component makers discussed their latest compact designs for next-generation coherent transmission line cards and modules.
NeoPhotonics detailed its micro-ITLA narrow linewidth tunable laser (micro-ITLA) that occupies less than a third of the area of the existing ITLA design. The company also announced a small form factor intradyne coherent receiver (SFF-ICR), less than half the size of existing integrated coherent receivers (ICRs).
NeoPhotonics supplies components to module and system vendors, and says customer interest in the second-generation coherent components is for higher port count line cards. "Instead of 100 Gig on a line card, you can have 200 or 400 Gigabit on a line card," says Ferris Lipscomb, vice president of marketing at NeoPhotonics. Moving to pluggable module designs will be a follow-on development, but for now, the market is not quite ready, he says.
An integrated coherent transmitter for metro, combining a tunable laser and integrated indium phosphide modulator in a compact package is also offered by NeoPhotonics.
The laser has two outputs - one output is modulated for the transmission while the second output is a local oscillator source feeding the coherent receiver. About half of all 100Gbps designs use such a split laser source, says Lipscomb, rather than two separate lasers, one each for the transmitter and the receiver. "That means that one transponder can only transmit and receive the same wavelength and is a little less flexible but for cost reduction that is what people are doing," says Lipscomb.
Oclaro is now sampling to customers its next-generation indium phosphide-based coherent components. The company, also a supplier of coherent modules, says the components will enable CFP and CFP2 pluggable coherent transceivers. The pluggable modules are suited for use in metro and metro regional networks.
Oclaro's components include an integrated transmitter comprising an indium phosphide laser and modulator, and the SFF-ICR. Oclaro's micro-ITLA is in volume production and has an output power high enough to perform both the transmit and the local oscillator functions. The micro-ITLA is used for line cards, 5x7-inch and 4x5-inch MSAs module and CFP designs.
u2t Photonics is another company that is developing a SFF-ICR. The company gave a private demonstration at ECOC to its customers of its indium phosphide modulator for use with CFP and CFP2 modules. "We demonstrated technical feasibility; it is a prototype which shows the capability of indium phosphide technology," says Jens Fiedler, executive vice president sales and marketing at u2t Photonics.
u2t Photonics and Finisar both licensed 100Gbps coherent indium phosphide modulator technology developed at the Fraunhofer Heinrich-Hertz-Institute.
There are new coherent DSP chips coming out early next year
Also showcased was u2t's gallium arsenide modulator technology implementing 16-QAM (quadrature amplitude modulation) at ECOC, but the company has yet to announce a product.
JDSU also gave an update on its line side coherent components. It is developing an integrated transmitter - a laser with nested modulators - for coherent applications. "This work is underway as a technology for line side CFP and CFP2 modules," says Ed Murphy, senior director, communications and commercial optical products at JDSU.
The difference between the CFP and CFP2 coherent modules is that the DSP system-on-chip is integrated within the CFP. Acacia's AC-100 CFP is the first example of such a product. For the smaller CFP2, the DSP will reside on the line card.
"There are new DSP [chips] coming out early next year," says Robert Blum, director of product marketing for Oclaro's photonic components. The DSPs will require a power consumption no greater than 20W if the complete design - the DSP and optics - is to comply with the CFP's maximum power rating of 32W.
Pluggable coherent modules promise greater port densities per line card. The modules can also be deployed with traffic demand and, in the case of a fault, can be individually swapped rather than having to replace the line card, says Blum.
JDSU says two factors are driving the metro coherent market. One is the need for lower cost designs to meet metro's cost-sensitive requirements. The second is that the metro distances can use essentially the same devices for 16-QAM to support 200Gbps links as well as 100Gbps. "It is the same modulator structure; maybe a few of the specs are a bit tighter but you can think of it as the same device," says Murphy.
System vendors have trialled 200Gbps links but deployments are expected to start from 2014. The deployments will likely use lithium niobate modulators, says Murphy, but will be followed quickly by indium phosphide designs.
NeoPhotonics used ECOC to declare that it has now integrated the semiconductor optical component arm of Lapis Semiconductor which it acquired for $35.2 million in March 2013.
Ferris Lipscomb
The unit, known as NeoPhotonics Semiconductor GK, makes drivers and externally modulated lasers. "These are key technologies for high-speed 100 Gig and 400 Gig transmissions, both on the line side and on the client side," says Lipscomb.
NeoPhotonics, previously a customer of Lapis, decided to acquire the unit and benefit from vertical integration as it expands its 100 Gig and higher-speed coherent portfolio.
Owning the technology has cost and optical performance benefits, says Lipscomb. It enables the integration of a design on one chip, thereby avoiding interfacing issues.
Further reading:
Part 2, click here
Reader Comments (1)
Correction: NeoPhotonics Semiconductor GK makes drivers and externally modulated lasers, not as stated when the article was first posted.