Broadband access networks form the essential last mile for today’s data connectivity. In recent years, advancements in access network technologies such as 25G-PON have revolutionized the broadband speeds delivered to homes and enterprises. Supporting these new capabilities are enhancements in network control and orchestration mechanisms, where the introduction of programmable networking enabled by the software-defined access network (SDAN) is rapidly redefining how access networks are provisioned, controlled and managed.
Shift to SDAN
Before the introduction of SDAN, broadband access networks deployed the Element Management System (EMS), a highly fragmented architecture that required a high number of separately managed vendor-specific EMS nodes across different access technologies such as Passive Optical Network (PON), Digital Subscriber Line Access Multiplexers and Multi-Services Access Networks. The EMS relies on a Graphical User Interface-based system and features limited functionalities, resulting in a black box approach to network management.
Consequently, a high degree of customization became necessary every time different vendors, access technologies and network functions were introduced, making end-to-end integration and provisioning inefficient and costly.
SDAN was built to overcome these challenges. It is based on open APIs, supporting multiple vendors with flexible device modelling. It offers automation, customization and is able to integrate disaggregated virtual and physical network functions. This enables the seamless introduction of new access technologies such as GPON and XGS-PON, drives virtualization and expedites the creation of new services. The transitioning from EMS to SDAN essentially drives operational efficiencies and flexibility across the access network.
Introducing the Altiplano Access Controller
In supporting operators’ transition to fully virtualized access network control, Nokia offers a suite of SDAN solutions that facilitate the evolution from legacy to hybrid to software-defined access networks.
As an integral component of Nokia’s SDAN solution offerings, Nokia’s Altiplano Access Controller was launched in 2019 to offer operators a unified network management and automation interface for their fixed networks, across multi-vendor and multi-technology environments. It combines the functionalities of OSS, orchestration, automation and analytics into a single interface that enables operators to manage and dynamically provision their fixed access network from the cloud. This includes the management and automation of copper and fiber access nodes, fiber aggregation points and fixed wireless gateways, provided by Nokia or any other third-party vendor.
Altiplano Access Controller Features
The Altiplano Access Controller is managed from the Altiplano Cloud Platform, a Linux-based modular and programmable platform that enables operators to easily deploy applications, devices and services onto their fixed networks. The cloud platform offers all the functionalities of a traditional Network Management System (NMS) with a host of advanced features including software-defined and virtualization capabilities. The platform comes with access to the Altiplano Developer Portal, with a fully-documented software development kit (SDK).
Altiplano Cloud Platform
Deciphering key principles for Altiplano microservices
The Altiplano Access Controller operates on a robust cloud-native architecture where isolated micro-services can be deployed to cater for different network management operations. Altiplano is an open modular platform centered around open and standardized interfaces to allow cloud control and multivendor interoperability. Apart from the overarching Cloud CO reference architecture in Broadband Forum (BBF)’s TR-384, these microservices conform to a number of other specifications, categorized by the following key principles:
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Always- On
Premised on the BBF TR-301 specification that theorizes a Persistent Management Agent Aggregation function enabled controller, Altiplano features not only uninterrupted cloud access to critical network information, but is also equipped with a host of ‘always-on’ features including 24/7 provisioning, constant data accessibility, always-on access nodes, continuous network versioning and integration. -
Virtualization
Through the virtualization of network functions, Altiplano facilitates operators with the flexibility to both elastically scale and distribute functions across the network as per demand and latency requirements. The Altiplano Access Controller can be deployed virtually anywhere - on VMs or containers, and in public or private clouds. The virtualized OMCI, specifically, confirms to BBF WT-451, which defines the interfaces for the management of ONUs. -
Intent-based Abstraction
The Altiplano Access Controller operates in an abstracted intent model, whereby the network continually self-adjusts to meet a set of service level policies, dynamically remedying any deviations. It provides open interfaces, creating an environment that is both technology- and vendor-agnostic, in line with BBF TR-411. -
Closed-loop Automation
Altiplano is compliant with the Automated Intelligent Management framework outlined in BBF TR-436, thus positioning it as a key enabler of AI/ML-driven intelligent decision making. With real-time network analytics, operators can establish closed-loop automation routines that continuously optimize and adjust network performance. -
Network Sharing and Slicing
The Altiplano Access Controller enables network slicing, as specified in BBF TR-370. It can share a virtual partition of the network and provide tenants control across physical components, such as a network port or card, or logical attributes, such as VLAN or bandwidth, allowing operators to offer new services such as Network-as-a-Service.
Altiplano Access Controller Interface
Enhancing operator monetization
The recent pandemic is a good case in point for SDAN. In a short span of time, broadband access networks, globally, experienced a dramatic surge in traffic as more people stayed at home and accessed a plethora of bandwidth-hungry applications including online video meetings and HD video streaming. During these times, the benefits from SDAN-driven programmability and flexibility became more evident, as bandwidth constraints necessitated intelligent, real-time provisioning of available network resources.
Orange Labs Networks, which was already trialling Nokia’s SDN programmable Lightspan FX fiber nodes and the Altiplano cloud platform, saw SDAN’s potential going beyond ensuring service quality to enabling innovative offerings such as slicing-enabled cloud gaming. Automation and network slicing in the access network, interestingly, map fixed network capabilities closer to that of 5G’s.
Christian Gacon, VP Wireline Networks at Orange Group said, “In the long run, we have to be consistent between the mobile network and the fixed network, in order to deliver end-to-end services and so we are to prepare ourselves for network slicing even in the fixed network.”
The SDAN Advantage
With more than 20 wins since its introduction, Altiplano is currently being trialled and deployed in various locations across the globe. While most deployments involve upgrading the underlying access technology, for example from GPON to XGS-PON or introducing G.fast or Fixed Wireless Access, operators are also targeting greenfield FTTH deployments as well as deployments over existing technologies, such as GPON.
Altiplano Access Controller GUI
In December, Metrotel, an Argentinian operator providing IP telecommunications, internet and data center services, deployed Altiplano to build a state-of-the-art shared fiber infrastructure based on PON technology. The platform is expected to enable Metrotel to optimize services for different markets namely financial services, media, hospitality and the government using network slicing, while at the same time, advancing its position as a broadband wholesaler and provider of 5G mobile backhaul services in the country.
Germán Garay, CTO at Metrotel, said “We chose Nokia for their comprehensive but also highly dynamic solution; new and scalable PON technologies; software oriented around shorter innovation cycles; and an architecture based on microservices, automation and virtualization. This makes the best use of both new and existing infrastructure and gives our customers the best possible value.”
Earlier this month, DELTA Fiber of Netherlands also inked a deal with Nokia to expand its broadband network using Nokia’s XGS.PON solution. The collaboration will see the operator adopting SDAN for its network leveraging Nokia’s Altiplano, which will be deployed in combination with Microsoft Azure cloud-based services. In his statement, John Wittekamp, CTO of DELTA Fiber, expects trends which emerged during the pandemic, for example, home working and immersive entertainment, to continue into the future. Already the fastest network in Netherlands, Nokia’s solutions will enable the operator to deliver, as needs evolve, up to 25Gb/s on its 25G-PON ready network.
Conclusion
SDAN introduces increased efficiency in how operators abstract and automate their network infrastructure to form new and exciting revenue streams, and to merge the capabilities of both fixed and mobile networks to form unified, yet customized offerings for various verticals. This will form a key competitive advantage for operators in linking up humans and machines in a complex web of high-speed data communications that will continue to fuel our economies and keep our societies connected.
