Nex Gen PON
TC3 Update on CORD (Central Office Re-architected as a Data center)
Timon Sloane of the Open Networking Foundation (ONF) provided an update on project CORD on November 1st at the Telecom Council’s Carrier Connections (TC3) summit in Mt View, CA. The session was titled:
Spotlight on CORD: Transforming Operator Networks and Business Models
After the presentation, Sandhya Narayan of Verizon and Tom Tofigh of AT&T came up to the stage to answer a few audience member questions (there was no real panel session).
The basic premise of CORD is to re-architect a telco/MSO central office to have the same or similar architecture of a cloud resident data center. Not only the central office, but also remote networking equipment in the field (like an Optical Line Termination unit or OLT) are decomposed and disaggregated such that all but the most primitive functions are executed by open source software running on a compute server. The only hardware is the Physical layer transmission system which could be optical fiber, copper, or cellular/mobile.
Author’s Note: Mr. Sloane didn’t mention that ONF became involved in project CORD when it merged with ON.Labs earlier this year. At that time, the ONOS and CORD open source projects became ONF priorities. The Linux Foundation still lists CORD as one of their open source projects, but it appears the heavy lifting is being done by the new ONF as per this press release.
A reference implementation of CORD combines commodity servers, white-box switches, and disaggregated access technologies with open source software to provide an extensible service delivery platform. This gives network operators (telcos and MSOs) the means to configure, control, and extend CORD to meet their operational and business objectives. The reference implementation is sufficiently complete to support field trials.
Illustration above is from the OpenCord website
Highlights of Timon Sloane’s CORD Presentation at TC3:
- ONF has transformed over the last year to be a network operator led consortium.
- SDN, Open Flow, ONOS, and CORD are all important ONF projects.
- “70% of world wide network operators are planning to deploy CORD,” according to IHS-Markit senior analyst Michael Howard (who was in the audience- see his question to Verizon below).
- 80% of carrier spending is in the network edge (which includes the line terminating equipment and central office accessed).
- The central office (CO) is the most important network infrastructure for service providers (AKA telcos, carriers and network operators, MSO or cablecos, etc).
- The CO is the service provider’s gateway to customers.
- End to end user experience is controlled by the ingress and egress COs (local and remote) accessed.
- Transforming the outdated CO is a great opportunity for service providers. The challenge is to turn the CO into a cloud like data center.
- CORD mission is the enable the “edge cloud.” –>Note that mission differs from the OpenCord website which states:
“Our mission is to bring datacenter economies and cloud agility to service providers for their residential, enterprise, and mobile customers using an open reference implementation of CORD with an active participation of the community. The reference implementation of CORD will be built from commodity servers, white-box switches, disaggregated access technologies (e.g., vOLT, vBBU, vDOCSIS), and open source software (e.g., OpenStack, ONOS, XOS).”
- A CORD like CO infrastructure is built using commodity hardware, open source software, and white boxes (e.g. switch/routers and compute servers).
- The agility of a cloud service provider depends on software platforms that enable rapid creation of new services- in a “cloud-like” way. Network service providers need to adopt this same model.
- White boxes provide subscriber connections with control functions virtualized in cloud resident compute servers.
- A PON Optical Line Termination Unit (OLT) was the first candidate chosen for CORD. It’s at the “leaf of the cloud,” according to Timon.
- 3 markets for CORD are: Mobile (M-), Enterprise (E-), and Residential (R-). There is also the Multi-Service edge which is a new concept.
- CORD is projected to be a $300B market (source not stated).
- CORD provides opportunities for: application vendors (VNFs, network services, edge services, mobile edge computing, etc), white box suppliers (compute servers, switches, and storage), systems integrators (educate, design, deploy, support customers, etc).
- CORD Build Event was held November 7-9, 2017 in San Jose, CA. It explored CORD’s mission, market traction, use cases, and technical overview as per this schedule.
Service Providers active in CORD project:
- AT&T: R-Cord (PON and g.fast), Multi-service edge-CORD, vOLTHA (Virtual OLT Hardware Abstraction)
- Verizon: M-Cord
- Sprint: M-Cord
- Comcast: R-Cord
- Century Link: R-Cord
- Google: Multi-access CORD
Author’s Note: NTT (Japan) and Telefonica (Spain) have deployed CORD and presented their use cases at the CORD Build event. Deutsche Telekom, China Unicom, and Turk Telecom are active in the ONF and may have plans to deploy CORD?
- This author questioned the partitioning of CORD tasks and responsibility between ONF and Linux Foundation. No clear answer was given. Perhaps in a follow up comment?
- AT&T is bringing use cases into ONF for reference platform deployments.
- CORD is a reference architecture with systems integrators needed to put the pieces together (commodity hardware, white boxes, open source software modules).
- Michael Howard asked Verizon to provide commercial deployment status- number, location, use cases, etc. Verizon said they can’t talk about commercial deployments at this time.
- Biggest challenge for CORD: Dis-aggregating purpose built, vendor specific hardware that exist in COs today. Many COs are router/switch centric, but they have to be opened up if CORD is to gain market traction.
- Future tasks for project CORD include: virtualized Radio Access Network (RAN), open radio (perhaps “new radio” from 3GPP release 15?), systems integration, and inclusion of micro-services (which were discussed at the very next TC3 session).
Addendum from Marc Cohn, formerly with the Linux Foundation:Here’s an attempt to clarify the CORD project responsibilities:
- CORD is an open reference architecture. In that sense, CORD is similar to the ETSI NFV Architectural Framework, ONF SDN Architecture, and MEF LifeCycle Services Orchestration (LSO) reference architectures.
- As it is a reference architecture, it is not an implementation, and is maintained by the Open Networking Foundation (ONF), which merged with ON.LAB towards the end of 2016.
- OpenCORD is a Linux Foundation project announced in the summer of 2016. It is focused on an open source implementation of the CORD architecture. OpenCord was derived from the work undertaken by ON.LAB, prior to the merger with ONF in 2016.
- For technical details, visit the OpenCORD Wiki
- Part of the confusion is that if one visits the Linux Foundation projects page, CORD is listed, but the link is to the OpenCord website.
Verizon trial validates NG-PON2 interoperability via its OpenOMCI specification; 5G backhaul spending
Verizon reported a successful trial of next-generation passive optical networking NG-PON2 technology using the carrier’s OpenOMCI specification. The OpenOMCI specification is aligned with ITU-T Recommendation G.989.3, but there are different versions from several carriers.
It’s important to note that this is Verizon’s own version of the OpenOMCI spec. Verizon, along with ADTRAN, Broadcom, Cortina Access, Ericsson/Calix and Intel, worked together to develop the OpenOMCI specification that led to the successful trial. The specification defines the OLT-to-ONT interface and is aligned with the ITU-T Recommendation G.989.3. Since the initial NG-PON2 trial by Verizon in December 2016 , these companies intend to make their hardware and software compliant and are actively contributing to the OpenOMCI specification.
AT&T also published an OpenOMCI specification just a few weeks ago, based on ITU-T G.988 Managed Entities. AT&T intends to deploy an XGS-PON architecture as part of the overall FTTP solution for its Lightspeed service, hence its OpenOMCI spec differs from Verizon’s FiOS-based one. XGS-PON is championed by Nokia (who is not part of Verizon’s vendor group) and also delivers 10Gbit/s to customers.
The trial at Verizon’s technology center in Waltham, MA involved optical network terminal management and provisioning.
By outlining the tools necessary to model a multi-wavelength PON, Verizon says the OpenOMCI specification optimises the number of managed entities and methods that can be used to implement a particular service function while disallowing vendor-proprietary objects and features that have provided a major obstacle for interoperability efforts until now. The OpenOMCI also includes specific managed entities that, in Verizon’s opinion, improve the stability of PON systems. With today’s PON deployments, telcos are obliged to use the same vendor for both optical line terminals (OLT) and optical network terminals (ONT) which prevents multi-vendor interoperability.
“The NG-PON2 interoperability effort is important, not only for Verizon but for NG-PON2 technology, and is based on lessons learned over the last 13 years of PON deployment and great partnerships,” said Vincent O’Byrne, PhD and director of technology at Verizon. “We see this work as removing a major roadblock and helping accelerate NG-PON2 deployment.”
O’Byrne told FierceTelecom that the OpenOMCI specification will help to ensure the company can deploy an array of OLTs and ONTs in its network. He said:
“Since October 2016 we have been working with the vendors on enabling interoperability to mix and match one vendor’s OLT with another vendor’s ONTs, which is an object we have had since we started deploying BPON in 2004. “We have been working with these vendors and have developed OpenOMCI communications between the OLT and the ONT and how that issue is handled for NG-PON2.”
Along with ONT management and provisioning, the trial investigated transmission convergence layer features that allow support of not only business and residential traffic but wireless transport services. These features are a unique addition to NG-PON2 compared to other PON systems.
“We continuously sought the various contributors’ feedback and constructive input,” said Denis Khotimsky , Distinguished Member of the Technical Staff and Verizon’s lead engineer for the trial. “NG-PON2 technology creates specific challenges for the management layer to handle, such as multi-wavelength operations, pluggable optics and multiple interface enhancements. The Verizon OpenOMCI specification meets those challenges.”
Representatives of several telcos interested in the NG-PON2 technology – including Deutsche Telekom, SK Telecom and Vodafone – participated in the trial as virtual observers, which gave them access to the specification, test plans and readouts.
Following the successful completion of the trial, Verizon shared its OpenOMCI specification with the industry for possible inclusion within the appropriate standards. A copy of Verizon OpenOMCI specification can be found here.
Addendum: On July 18th, Fierce Telecom reported: 5G backhaul spending to reach $2B by 2022, NG-PON2 to dominate
“The technology that will dominate 5G backhaul will be NG-PON2,” CIR stated. “By 2022, more than $890 million will be spent on this technology for 5G backhaul.”
The analyst firm noted that Verizon has selected NG-PON2 for 5G backhaul. Top vendors, including Cisco, Nokia, Huawei, Calix, Adtran, Ericsson and Alcatel-Lucent all have PON solutions for 5G backhaul.
NG-PON2 should remain the most popular technological choice, provided prices come down as expected, based on the development of less costly tunable components, CIR said. Most of the suppliers of those components will be based in China, the firm expects.
CIR also calculated that more than 170,000 fiber miles (280,000 kilometers) of cable is expected to be shipped for 5G backhaul applications in 2022, with major fiber and cable suppliers such as Corning already showing signs of specifically targeting 5G infrastructure with their products.
The firm also noted that the introduction of high-speed wireless may have the side effect of reducing the need for fiber to the premise/home (FTTP/FTTH).
There will be some short-term uncertainty until 5G standards are finally ratified, but CIR concluded that “5G is potentially a massive opportunity for the fiber optics industry, with this taken to include opportunities for the makers of modules and components as well as the fiber/cable manufacturers themselves.”