Open and Disaggregated FTTx

FTTx ie Fibre to the x is a collective term used for various optical fibre delivery topologies categorized by the infrastructure deployed for last-mile/access connectivity (The variable x is here represents the deployed infrastructure ie B for buildings, H for Homes, P for Premise, N for Node, O for Offices etc.). On the other hand, pFTTx ie Programable FTTx adds a layer of software intelligence to the existing monolithic white-box-based FTTx infrastructure. It can be simply referred to as an SDN-NFV, micro-services-oriented, cloud-based network solution that brings more flexibility, cost efficiency and service excellence to digital networks. It drastically reduces time to market for new digital services, sets the ball rolling for edge computing by disaggregating broadband networks and re-architecting central offices. This technology will shape the future of broadband while connecting millions of people and devices seamlessly.

Some of the key features of pFTTx include: Programmability - across hardware and software empowers operators to have better control; Open ecosystem - through API interfaces defined by the community allows true vendor-neutrality; Disaggregation - of hardware and software allows launching new services up to 8-10 times faster, using cloud delivery models and technologies; COTS deployment – COTS brings flexibility to the procurement and integration of network equipment; Zero-touch provisioning - automates regular functions keeping human intervention to a minimum.

Business benefits of pFTTx include:
a) Reduction in hardware and software costs with white boxes at the edge for RAN, GPON/XGSPON/NG-PON2
b) Service providers can have complete control over their own network and can solve their business problems and innovate as required
c) With last-mile network becoming programmable and agile, and with the control over translating business requirements to technical features, the infrastructure of the service providers will become lock-in free
d) Open infrastructure at the last mile significantly reduces the time-to-market and leads to revenue growth
e) Faster roll-out of premium and innovative services lead to an increase in average revenue per user
f) Programmable and agile network ensure a better quality of experience, reducing subscriber churn

SDN or commonly know as Software Defined Networking is a unique network architecture approach that helps to virtualize the network by separating the control plane (that manages the network) from the data plane (where the traffic flows). In contrast to traditional networking where integrated hardware and software is used to direct traffic across the network, SDN uses a smart controller running specialised software to centrally manage all network traffic in the datacentre and a series of routers & switches that forward packets of traffic.

SDN comprises of three basic networking layers namely infrastructure layer/data plane which contains the network forwarding equipment/device comprising of the networking equipment. The second layer is known as the control layer/control plane which provides forwarding instructions and a set of configurations to the infrastructure layer. The layer is responsible for configuring the infrastructure layer by receiving a service request from the third layer called the application layer/management plane. The control layer maps the service request onto the infrastructure layer in the most optimum way possible, thus dynamically configuring it. Coming to the application layer, this is where cloud, business, and management applications place their demands for the network onto the control layer. Each of these layers and their application side are programmable interfaces designed to be OPEN. OPEN means they can have multiple vendor's equipment on the infrastructure layer, multiple vendor's components of control on the control layer, and multiple vendor's applications on the application layer.

The key advantages of Software Defined Networking (SDN) are:- Centralized network control, Network Programmability, Dynamic upscaling and downscaling of network resources, Openness, Dedicated support for specialised applications & use cases, and Individual security policy support at each node. Over the years SDN (Software Defined Networking) has evolved from just being deployed in datacentre networks to now, SD-WAN (Software-Defined Wide Area Network), Microsegmentation, and NFV (Network Function Virtualisation).

NFV or Network Function Virtualisation basically refers to virtualising proprietary hardware like routers, switches, load balancers, WAN accelerators, and firewalls, etc. into software-driven functions that run in a virtual machine (VM). In comparison to traditional data centres that are vendor-specific, purpose-built, expensive, tedious to build, difficult to upgrade, and slow in deployment, NFV resolves the issue by decoupling the hardware from the software.

Network Function Virtualisation (NFV) typically requires Commercial off-the-shelf (COTS) hardware like x86 servers with storage and switching to virtualise all the networking functions to form a cloud data centre.

The NFV architecture has four major components:

a) NFVI - Network Function Architecture Infrastructure (NFVI) is a resource pool of storage, computes and network function resources in the NFV environment. It divides into three components hardware resources (RAM, Servers, and NAS, etc.), virtualisation layer that enables the software to progress independently from the software using specialised tools (KVM, QEMU, VMware, Open Stack etc.), and virtual resources (virtual Compute, virtual storage & virtual network).

b) VNF - Virtualised network function (VNF) are software implementations of network functions. VNFs can be combined together to establish a full-scale telecommunications service, also referred to as service chaining. Examples of VNF includes vIMS, vRouter, vFirewall etc.

c) MANO- Management and Network Orchestration unit (MANO) comprises of three parts, virtualised infrastructure manager (controls and manages the interaction of VNFs with NFVI network, compute and storage resources. It also has necessary deployment and monitoring tools for the virtualisation layer), VNF Manager(Manages the lifecycle of VNF instances. It is responsible to initialise, update, query, scale and terminate VNF instances), Orchestrator (Manages the lifecycle of network services like instantiation, policy management, performance measurement and KPI monitoring).

d) OSS/BSS - OSS deals with network management, fault management, configuration management, service management and element management. BSS deals with Customer Management, Operations Management, Order Management, Billing and Revenue Management.