Heard of F5G?

Min He
14 min readAug 6, 2020

Let’s play a game of guessing your age. First, click the youtube video below.

If the sound is familiar to you and brings a smile on your face, I have 80% confidence that you are over 40 years old. But if you find the sound annoying, and it feels like an old screaming machine about to break, your age is likely under 35.

The sound is the dial-up internet access tone in the 90s and indicates your computer has successfully connected to your internet service provider (ISP), ready for you to surf. The different tunes show the different handshaking stages between your and ISP’s Modem.

Now you get the cue, we will talk about the evolution of the fixed network, aka the wireline network, for broadband access.

You heard about the wireless 5G network and its enormous potential impact on our lives. But F5G? I bet the term is pretty new to you.

The acronym F5G is pretty new in the networking industry, and it stands for the Five Generation Fixed Network (F5G). In February 2020, the European Telecommunications Standards Institute (ETSI) officially launched the F5G Industry Specification Group (F5G ISG) to push for the standardization of works on F5G. Initially, the group will be focusing on:(ETSI, 2020)

  • F5G use cases
  • The landscape of F5G technology and standards
  • Definition of fixed network generations
  • The architecture of F5G
  • F5G quality of experience

The mobile network has an apparent boundary of generations of technologies; it has passed the 1G (AMPS), 2G (GSM/CDMA), 3G (WCDMA/CDMA2000/TD-SCDMA), 4G (LTE TDD/LTE FDD) era, and now getting into 5G represented by 5G NR technology. Compare with the previous generation, each new generation utilizes a different spectrum, offers higher bandwidth throughput, lower latency, and drive different business scenarios. The arrival of 5G global deployment has promoted a new round of prosperity in the mobile communications industry, providing critical enablers for the digital transformation of our lives.

Although the 5G mobile communication is in the spotlight right now, the fixed network technology is under rapid development and getting into a new era that equivalently enables the digital transformation of all walks of life.

In this article, we will explore what drives F5G, its motivation, and the exciting new business scenarios that F5G can potentially bring to us.

Fix Network Broadband Development Generations

The sound you heard earlier is the sound of F1G. The 1st Generation Fixed Network for broadband access, which is popular in the late ’80s till the end of the ’90s. Take a moment to recall how your home internet access is developing; you can feel the beats of fixed network technology evolution. Started with dial-up Access via phone line, then ADSL, then cable, then fiber. On the killer application in each era, start with AOL, then Google, then Youtube, then Netflix.

Fix broadband network development stages (Ao Li, 2020)

We are now getting into the early stage of mass deployment of F5G systems, which promises Gigabit ultra-fast broadband symmetric access with low latency. The technologies are getting mature, more business drivers are present, and the demands are picking up.

Business Drivers for F5G

It is comm knowledge that the optical network delivers the highest throughput, lowest latency, and the fastest service restoration. However, the cost of building an optical network infrastructure is high, laying fibers underground is expensive. In 2016, Google halted the expansion plans of its FTTH (Fiber To The Home) project after serving seven cities in 3 states for about 200k households due to the cost factors combine with a lack of demands. Because of a lack of killer apps to take advantage of the Gigabit bandwidth to justify the higher cost for homeowners.

The mass deployment of F5G needs other business drivers. For the last two years, we see the emerging of new business drivers that propel the rapid deployment of F5G.

Wireless 5G propels F5G development.

Wireless 5G global deployment demands higher bandwidth and lower latency for its backhaul network, which provides the all-important connection from the Radio Access Network (RAN) to the packet core, which subsequently makes the connection to the public Internet.

Future cross-hauling of 5G network (Hassim Haddaji et. cl 2018)

The 5G base station site estimated that by 2025, the total number of global 5G base stations will reach 6.5 million (WiseGuys Reports, 2020). China carriers will deploy a total of 500,000 5G base stations along this year, according to the country’s Ministry of Industry and Information Technology (MIIT). Each 5G base station, especially the macro base station, to meet the throughput and latency requirement, is commonly using fiber as the backhaul mechanism. The emerging cross haul architecture utilizes even more fiber connectivities to serve both front haul and backhaul to deliver even better cost-effectiveness.

5G is introducing several new features such as enhanced coordinated multipoint (CoMP), dual connectivity (X2 and eX2 interfaces), and carrier aggregation that will make radio access networks (RAN) more complex to construct.

Together these changes will put greater demands on the transport network and have a disruptive impact on the optical network architecture to accommodate these requirements better.

5G is different from previous mobile generations in three ways:

  • Densification or an increase in the number of cell sites per unit area along with greater fiberization of cell towers
  • Cloudification or greater centralization of baseband resources that connect to “street level” radio nodes over optical fiber
  • Disaggregation or flexible and “software-centric” separation of control and data plane for higher scalability and dynamic resource allocation.

As a result, with the advent of 5G, optical networks are expected to display three significant changes.

  1. Mobile Backhaul is evolving to Crosshaul (X-haul): Mobile backhaul refers to the section of the telecom network that transports cellular traffic from base stations at cell towers to the nearest traffic switching center. While multiple backhaul options are available today (optical fiber, microwave or copper) with the arrival of pre-5G/5G mobile operators are fast gravitating towards optical fiber as the physical medium of choice. 5G is introducing new radio access architectures such as C-RAN (centralized RAN) using new protocols such as CPRI/eCPRI to connect multiple remote radio heads at street level to a centralized cloud-resident baseband unit at the macro base station. While optical fiber is the popular choice for this “front-haul” network, 5G also imposes additional demands in terms of latency, jitter, scalability, and connection bandwidth on the backhaul. These requirements are expected to be met through a new “cross-haul” architecture that integrates front-haul and backhaul in a single transport network to achieve an overall reduction in CAPEX and OPEX. The 5G Cross-haul transport will use intelligent multiservice edge devices that combine heterogenous broadband access media (wireless or wired), flexible service delivery (enterprise or residential), and packet transmission services over optical fiber.
  2. Hyperscale Metro and Core Networks: High-capacity optical communications is a crucial technology driving network transformation in the Metro and Core networks. Thanks to advances in this area, a single optical fiber strand can carry tens of terabits of traffic today through modern techniques such as dense lightwave multiplexing (DWDM), optical amplification, reconfigurable optical add-drop multiplexing (ROADM), and coherent optical processing. 5G will capitalize on recent advances in coherent DWDM technology to build hyper-scale metro and core networks that transmit 100G/200G/400G bit rates per wavelength over thousands of kilometers at the lowest cost per bit. Coherent DWDM achieves these gains primarily through superior modulation formats that make use of amplitude, phase, and polarization of light waves and better compensation for chromatic dispersion and polarization mode dispersion (CD, PMD) through sophisticated digital signal processors. Advanced network functions such as multi-degree colorless/directionless/contentionless optical switching (CDC ROADM), universal terabit-scale OTN/PTN cross-connects (DXC), and generalized MPLS protocols (GMPLS) for efficient automated switching at the wavelength layer enable the system to optimally pack service traffic over fewer wavelengths and engineer a highly cost-effective solution in high-bandwidth DWDM networks.

5G represents a significant advance over previous mobile technology generations due to an explosion in the number of network-enabled IoT devices, greater fiberization and densification of cell sites, and a “cloudified” RAN architecture. The magnitude of these changes is such that it is likely to have a transformational impact on the 5G optical network architecture extending right from the Access to the Metro and Core segments. The emerging cloud architecture with its software-centric network paradigm also presents opportunities for telecom vendors and service providers to evolve innovative products and services that can contribute to the overall growth of the global telecom industry. (Tejas Networks, 2019)

The synergy between F5G and 5G will accelerate the opening of a smart world of the Internet of Everything. It is predicted that by 2025, the number of global connections will reach 100 billion, the penetration rate of Gigabit home broadband will reach 30%, the coverage of 5G networks will reach 58%; the number of VR/AR personal users will reach 337 million, enterprise VR /AR’s penetration rate will reach 10%; 100% of enterprises will adopt cloud services, 85% of enterprise applications will be deployed in the cloud, and the annual global new data volume will reach 180ZB. Network connectivity is becoming a ubiquitous natural presence, injecting momentum into the digital economy, and enabling the ultimate business experience for everyone, every family, and every organization. (HHT Group, 2020)

Fog networking cries loud for F5G

Fog computing extends the concept of cloud computing to the network edge, making it ideal for the Internet of things (IoT) and other applications that require real-time interactions. Fog computing is one kind of edge computing where the computing resources reside on LAN endpoint, not necessary on the device with sensors. It processes the information from multiple sensor devices, thus has more powerful data processing capability than sensor IoT devices.

Credit: www.thinkebiz.net

The network connectivities to the Fog node varies from wireless to wireline. It makes a lot of business sense for those Fog nodes that serve large number of IoT devices and have high bandwidth and ultra-low latency requirements.

Optical Fog Node (Kiran Deep Singh, 2019)

A large number of required optical fog nodes further increases the optical network’s reaches and accelerates the deployment of F5G technology.

Bandwidth hunger from the home broadband user

By 2019, global 4K TV unit sales passed 100million. 8K Ultra HD TV, a technology that is just beginning to experience widespread use, is expected to grow significantly between 2019 and 2025, with unit sales increasing from half a million to around 31 million during that period.

Even though the killer apps for Gigabit network access is not yet very prominent, but 8K TV and CloudVR, Gaming is gradually showing up.

The black swan event of the Covid-19 pandemic fundamentally changes how we live out life. People spent an insane amount of time online: remote working, online meetings, online education, online fitness, and people spending more time on social video platforms like Youtube and TikTop demanded more bandwidth to meet the needs of everybody stuck at home. People are willing to pay more to get a better online experience because it becomes so essential to their daily lives.

In April 2020, New York Times article The Virus Changed the Way We Internet. It describes the traffic surge of online platforms since locked-down.

Work and study using online collaboration platforms
Communication with video chat platforms
Entertain via streaming platforms

Many experts think this kind of pattern will stay for a long time until the vaccine available.

This fact drives the demand for Gigabit home broadband access to another level that will propel the rapid deployment of F5G.

Technology Drivers of F5G

New ODN Technologies

XG(S)-PON Access

ONT/ONU 10G GPON, EPON ports growth forecast

10G PON (Passive Optical Network) is coming. The biggest reason is that 10G PON provides more benefits than GPON.

(1) Higher bandwidth: Compared with GPON, the downstream bandwidth of 10G PON increased by four times, and the upstream bandwidth increased by two times. For 2B scenarios that require symmetric broadband, symmetrical 10G PON can be deployed to support up to 4 times the relative GPON bandwidth.

(2) Lower latency: There are already some innovative technologies in the industry that can further reduce the latency of OLT / ONU to the microsecond level, meet the demanding requirements of special enterprise leased lines, and guarantee SLA.

(3) Higher cost performance: There is no need to modify the ODN network, the 10G PON upgrade only needs to replace the central office OLT equipment and the terminal ONT equipment. At the same time, after the bandwidth is increased, especially supporting symmetrical bandwidth can expand more application scenarios and increase revenue.

Compared with previous generations of fixed access technologies, 10G PON Gigabit networks have leapfrogged in terms of connection capacity, bandwidth, and user experience. For example, the uplink and downlink rates are as high as 10Gbps and the delay is reduced to less than 100μs.

Specifically, the first is all-optical connection, using vertical coverage of fiber-optic infrastructure to expand vertical industry applications, supporting business scenarios to expand more than 10 times, and the number of connections has increased by more than 100 times, enabling the era of fiber-optic connections.

Secondly, ultra-high bandwidth, network bandwidth capacity increased by more than ten times, and uplink and downlink symmetric broadband capabilities bring a little connection experience in the cloud era; Wi-Fi6 technology breaks through the last ten meters bottleneck of Gigabit home broadband.

Finally, it is the ultimate experience, supporting 0 packet loss, microsecond delay, and AI intelligent operation and maintenance to meet the extreme business experience requirements of home/enterprise users; the industry-leading OLT platform can support distributed cache and anti-video burst. 4K/8K video quick start and channel switching, and effectively support the video experience IntelliSense and troubleshooting.

WiFi 6 for the last 10 meters

The below graph shows the evolution of Wi-Fi standards from 1999 to 2019 and the improvements in performance, throughput, and network efficiency available with Wi-Fi 6 (802.11ax).

wifi evolution path (Intel)

The theoretical speed of WiFi 6 is 10Gbps. It achieves this speed increase by combining the 2.4GHx and 5GHz spectrum bands and employing MU-MIMO technology for both uplink and downlink data transfers.

Orthogonal Frequency Division Multiple Access (OFDMA) used in the Wifi 6 device allows a wireless channel to be divided into several sub-channels that can be used to carry data for a different device. This allows a single access point to communicate with more devices simultaneously.

The development of Wifi 6 is one of the key enablers for F5G. So end devices can take full advantage of the Gigabit broadband bandwidth offer by F5G. Wifi 6 router already commercially available for around $100.

Hyperscale Metro and Core Networks:

High-capacity optical communications are the fundamental technology driving network transformation in the Metro and Core networks. Thanks to advances in this area, a single optical fiber strand can carry tens of terabits of traffic today through modern techniques such as dense lightwave multiplexing (DWDM), optical amplification, reconfigurable optical add-drop multiplexing (ROADM), and coherent optical processing. F5G will capitalize on recent advances in coherent DWDM technology to build hyper-scale metro and core networks that transmit 100G/200G/400G bit rates per wavelength over thousands of kilometers at the lowest cost per bit. Advanced network functions such as multi-degree colorless/directionless/contentionless optical switching (CDC ROADM), universal terabit-scale OTN/PTN cross-connects (DXC), and generalized MPLS protocols (GMPLS) for efficient automated switching at the wavelength layer enable the system to optimally pack service traffic over fewer wavelengths and engineer a highly cost-effective solution in high-bandwidth DWDM networks.

F5G Demands Autonomous O&M

To dramatically improve the quality of user experience is one of the key characteristics of F5G for both the end-user experience and operator experience.

Like Wireless 5G, F5G will bring significant challenges to operate the network with more CPEs, more complex configuration scenarios, and the introduction of end to end network slicing functions. In the past 10 years, the networking industry has made significant progress with SDN, NFV, Cloud, and simplified network protocols. But, up coming intelligent era demands a lot more from the network service provider. Global CSPs fully realize that the current model of operation won’t be able to meet the challenge, and are in the process of transforming their networks, OSS/BSS systems, organization, and skillsets of people.

The networking industry has started to march on to the Autonomous Networks grand vision. The vision is to build cross domains, multi-layers, multi-vendors autonomous networks with self-fulfill, self-assured, self-defense capabilities, and ultimately delivers zero-touch, zero-wait, and zero-fault user experience for both end-users and operators. The standards bodies (TMF, ETST, 3GPP, GSMA, ITU) begin to define the necessary foundations for achieving Autonomous Network.

F5G demands autonomous O&M. It is one of the driving forces and contributes critical user scenarios for Autonomous Network.

Exciting Business Scenarios Unlocked by F5G

Like mobile 5G, F5G unlocks many existing new business opportunities or dramatically improves the user experience of existing applications: Enterprise Cloudification, Smart Manufacturing, Online Gaming, Cloud Desktop, Cloud VR, Smart City, Social Networking, Smart Education, Smart Home, and Telemedicine.

New Business Opportunities Unlocked by F5G (Artwork Credit: various sources)

Quality of Experience

to specify the end-to-end quality of experience (QoE) factors for new broadband services. It will analyze the general factors that impact service performance and identify the relevant QoE dimensions for each service.

In 2017, Akamai Technologies released a whitepaper that looked into the effect that poor QoE has on the user’s emotional state using skin response, facial coding, and other objective test methods. The followings are the key findings:

Higher quality streams generatd 19. 8% more emotional engagement (test method: galvanic skin response).

Lower quality streams generated a 16% increase in negative emotions (test method: facial coding).

Positive keywords scored 20–22% lower under lower quality (test method: implicit association testing).

Repeated quality issues could cause three-quarters of viewers to churn (test method: traditional survey).

F5G and Beyond

Fiber to Anywhere, Fiber to Everything

Fiber connectivity across the network (Commscope, 2019)
The number of CSPs offer 1G and 10G residential services (Ovum, 2019)

Pay tribute to F1G

Now you know what F5G is about, but the sound of F1G still buzz in your head. I highly recommend you listen to the below 700% slower version. It is creepy and beautiful at the same time, and suitable for any horror movie, even better, playing in the sports car of Elon Musk’s Starman traveling in the space.


ETSI, 2020 ETSI launches new group on 5th generation fixed network shifting the paradigm from fiber to the home to fiber to everything everywhere

Ao Li, 2020 Stepping forward together: F5G fixed broadband and 5G

Wise Guy Report, 2020 Global 5G Base Station Industry Research Report, Growth Trends And Competitive Analysis 2020–2026

Tejas Networks, 2019 The disruptive impact of 5G on optical network architecture

Shirly Lim, 2020 The future of the network:5G, Fiber Optics & Edge Computing

Kiran Deep Singh, 2019 Role of Optical Network in Cloud/Fog Computing

HHT Group, 2020 Keeping Pace with 5G: F5G Opens a New Era of Gigabit Broadband Business Prosperity

Nassim Haddaji, et al., 2018 Backhauling-as-a-Service (BHaaS) for 5G Optical Sliced Networks: AnOptimized TCO Approach

Commscope, 2019 Addressing the FTTA/FTTN challenge

Ella K and Nathaniel P, New York Times, 2020 The Virus Changed the Way We Internet

ISTC,2018 A 2019 Prediction: 10G-PON for All

Ovum 2019 10G PON Empowers Operators

Akamai Bit Rate and Business Model