Addressing the Challenge of Cloud Scale Metro Networks
By Jon Baldry
Director of Metro Marketing
Today Infinera announced the XTM II, our next-generation metro platform aimed at bringing cloud scale capacity and performance to metro networks. This is a significant announcement as it helps operators address a key challenge that exists today – bringing the scale needed to metro access and aggregation networks, and especially those with significant space and power constraints.
The reason this challenge exists is that operators are migrating to fiber-deep network architectures to support continued expansion of current service offerings, and a wave of potential new services such as virtual/augmented reality and self-driving cars. These architectures include examples such as Remote PHY (physical layer) in cable networks, migration to Long-Term Evolution Advanced (LTE-A) and ultimately 5G in mobile, and deeper fiber penetration in residential and business networks with fiber to the curb or the premise. This migration pushes fiber closer to end customers to support higher capacity and performance and requires packet-optical-based backhaul networks to follow. In addition, it propels this supporting backhaul network to provide significantly more capacity, ultra-low latency and the flexibility to cope with the increasingly dynamic nature of the traffic.
Network deployments: balancing functionality and capacity with available space and power
A few years ago, I interviewed one of our customers while I was updating our low power messaging, and he said to me, “You know Jon, for all my years of deploying networks, I know that real deployment ultimately comes down to two questions – available space and power.” It was such a relevant quote that we used it in our low power material at the time. He was right then and is even more so now, as networks become more fiber-deep and use facilities that are often limited in available space and power, such as telecoms huts and even street cabinets that were never designed to house high-capacity transport equipment. Once a technology or architecture decision is made for functionality or capacity in a site, then space and/or power can become limiting factors that force a reevaluation and a compromise if these resources aren’t available. Site expansion or power upgrades to these sites would be highly uneconomical and sometimes are not possible at all. Even where space and power are available, they are at a premium in these facilities, and therefore both are treated as critical factors in the network design process.
Further compounding the challenge of space and power is the trend toward Mobile Edge Computing and fog computing, which bring cloud-based applications closer to the end user. This approach brings many advantages to the end user or application, such as higher performance and simpler, cheaper end user devices with lower power consumption. However, in these architectures these same limited footprint facilities are being equipped with compute and storage infrastructure, increasing the importance of low power and highly dense packet-optical networking equipment. It also adds the requirement of very low latency transport to support the new and highly latency-sensitive applications being serviced from these “new” edge data centers.

XTM II, uniquely addressing the challenges of cloud scale metro networks
To support network operators with this challenge, Infinera has introduced the XTM II, a new breed of cloud scale metro platform with low power, low latency and high density. The platform is engineered to use 16 quadrature amplitude modulation (QAM)-based 200 gigabits per second (200G) per wavelength technology to drive power consumption down to as low as 20 watts per 100G service within a plug-in card, a figure which we believe is the lowest in the industry. The platform also provides an eightfold density increase over the previous generation of technology, making it ideal for space-constrained high-capacity deployments.
The XTM II combines Layer 1 transponder and muxponder options to transport a broad range of services and, critically, also contains Layer 2 packet-optical technology to directly support many Layer 2-based access architectures. All these options use Infinera’s Instant Bandwidth to adjust bandwidth on the fly. The inclusion of Layer 2 also means that these platforms have flexibility at Layers 0, 1 and 2 to support bursty traffic flows created by the next wave of applications and services that networks will need to support.
The platform helps prepare our customers for the future with flexible grid-based open line system components that support advanced modulation formats and the higher baud rates that we’ll see as we move to 400G per wavelength and beyond, to possibly 600G or even 800G per wavelength. Finally, the XTM II is forward and backward compatible with the rest of the XTM Series, meaning that the new XTM II chassis support all other XTM Series cards, and the new high-capacity XTM II cards are supported in the more than 30,000 deployed XTM Series chassis. We’ve been preparing for this step change in capabilities for some time, and the new XTM II chassis are already shipping to customers, enabling them to fully capitalize on the new capabilities of XTM II.
Our industry faces a huge challenge in pushing high-capacity metro networks closer to the edge while maintaining or enhancing low latency to support ever more dynamic fiber-deep access architectures. The XTM II will play a key role in connecting users to data centers and transporting operators to the cloud-based future across metro access, metro aggregation and metro core networks.
For more information, contact us.
Related links:
- Collateral: XTM II Solution Brief
- Press Release: Infinera Unveils XTM II for Cloud Scale Metro Packet-Optical Applications