Optical Innovation Puts Focus on DCI, SDN
In June, I hosted Huawei's second annual Optical Innovation Forum in Nice, which was attended by more than 150 attendees from network operators, service providers, analyst firms and component suppliers from around the world. While the forum is designed to cover optical topics of interest broadly, this year's event focused primarily around two key themes: metro data center interconnect (DCI) and transport software-defined networking (SDN).
Network traffic patterns have shifted due to growth in data centers (and the need to interconnect them), and due to the proliferation of content delivery networks (CDNs), which place video content closer to end users. Alcatel-Lucent (NYSE: ALU)'s Bell Labs research predicts that metro traffic will increase at nearly double the rate of backbone traffic over the next several years, and Heavy Reading has certainly seen a resurgence in optical activity in the metro over the past 18 months.
The evolution of 100G and 200G in metro networks was a big topic of discussion at the Optical Innovation Forum. Advanced modulation formats that drive higher bit rates, such as 16 QAM, impose distance limitations that can make them unsuitable for long haul transmission. However, with links generally less than 200 km (and often less than 100 km), metro DCI is an ideal application for 200G. As noted, traffic volumes here can be quite high, meaning that there is also a need for 200G connectivity.
For its part, Proximus (the new name and identity for Belgium's Belgacom SA (Euronext: BELG)) presented results of a recent 1 Tbit/s trial in which five 200G super channels using 16 QAM modulation transmitted 800 km. The trial used Huawei Technologies Co. Ltd. 's OSN 9800 equipment.
Optical module suppliers debated different approaches to delivering both 100G and 200G optics. Acacia Communications Inc. CTO Benny Mikkelsen promoted the digital coherent optics (DCO) approach to modules, in which the coherent DSP chip is contained within the optical module itself. Acacia's CFP-based DCO module has been shipping for some time and a CFP2-based version is in development.
On a separate panel, JDSU (Nasdaq: JDSU; Toronto: JDU) optical components group CTO Brandon Collings promoted the benefits of the analog coherent optics (ACO) approach to modules, in which the DSP chip remains outside the module packaging. As optical module space and, particularly, power requirements, become more stringent, the DCO approach becomes more difficult and ultimately impossible, Collings said, especially as the industry moves to CFP4.
On the transport SDN side, presentations and discussions focused on the progress that is being made within Europe and globally. Huawei referenced two main progress proof points. First, in March 2015, Huawei and Telefónica Peru announced the completion of a joint field trial using IP and optical layer integration using ROADMs at the photonic layer and SDN technologies to tie the IP and optical layers together. SDN technologies used were IETF-based, including PCEP, Virtual Network Topology Manager (VNTM) and GMPLS control plane.
The second reference point was a bandwidth-on-demand application introduced by China Telecom Fujian and China Telecom Beijing Research Institute in November 2014. CTBRI headed the application development, while Huawei supplied the SDN controller for the application, which is commercial.
Despite early progress, there is still much to be done. At last year's Optical Innovation Forum, Telefónica (one of Europe's most bullish SDN proponents) highlighted one of the key hurdles to wide-scale SDN deployments: confusion and stagnation in the wake of the ever-expanding sea of SDN standards and protocols. At this year's forum, Heavy Reading added two more key challenges alongside standards proliferation: lack of clearly defined business cases for SDN deployment and addressing security in SDN environments. We expect a concerted industry focus on overcoming these hurdles over the next year and look forward to measuring the progress on these fronts when we reconvene in Nice for the 2016 Optical Innovation Forum.
— Sterling Perrin, Senior Analyst, Heavy Reading
This blog is sponsored by Huawei.