by Drazen Vitez

Yesterday, …seems so far away

Hybrid Internet Access bonding started around 2015 as a fixed broadband solution for boosting DSL lines in underserved areas with excess capacity available in mobile networks, mainly LTE(-A). Some converged operators realized that it makes no sense for them to offer pure fixed wireless access (FWA) service, since they have DSL connectivity to virtually every household. 

In the same period FWA got very popular, very fast, because as mobile subscriptions peaked in most countries, mobile network operators (MNO’s) turned to households as additional revenue generating units (RGUs). LTE networks had significant spare capacity and adding FWA customers, with no commitment on service quality, was very profitable for MNO’s. The problem is, FWA customers use roughly the same amount of data as fixed broadband customers, which is 50-100 times more than mobile broadband customers on their smartphones. This quickly leads to disappointment with FWA service as people tend to start their Netflix streaming all at the same time. Churn rates of 30% are not uncommon for FWA services. As soon as MNO’s need to upgrade their networks in order to support FWA customers, this becomes a much less attractive business for MNO’s, but reality is often skewed in the marketing hype and pressure for growth is tremendous.

In response to the problems associated with FWA, we have seen a lot of M&A activities. MNOs were looking for fixed assets to become converged operators as they became aware that the growth cycle of a mobile only business is over with mobile subscriptions penetration peaked at ~130%. This once so prominent KPI is now completely irrelevant. So far, only a few of an increasing number of converged operators have realized the full potential of Hybrid Internet Access bonding, as they are struggling to converge teams from their mobile and fixed operations, but this is slowly changing. 

Instead of new and innovative “converged offers”, that would take full advantage of fixed and mobile assets to create additional value, operators rushed to the misleading marketing KPI  – “FMC subscriptions” showing how many customers subscribed to their new 4-play bundles. But bundles create little new value, except in reducing churn and this approach is suffocating innovative opportunities lying in the convergence of fixed and mobile networks and services. 

Standardization bodies, once lagging behind, now rushing ahead.

Since then, Broadband Forum (BBF) has issued several technical reports in an attempt to standardize the approach to building such solutions.

In July 2016, the BBF documented the available and foreseeable solutions from a network deployment perspective starting with TR-348 Hybrid Access Broadband Network Architecture. It was followed by TR-378 Nodal Requirements for Hybrid Access Broadband Networks in May 2019 which has defined a number of HCPE (Hybrid CPE) and HAG (Hybrid Access Gateway) requirements but is still documenting all available L3 and L4 solutions. Those technical reports have been written from a fixed network operator perspective and although the solutions are using the mobile network as a resource, these technical reports were missing the convergence perspective because there were too many hybrid access deployments defined in initial technical reports, and not all were suitable for a converged architecture.

At the same time, 3GPP was working on their own “hybrid access”, using both the 5G and Wi-Fi interface on smartphones in order to be able to steer, switch and split traffic over both available network connections. 4G/5G, being within the 3GPP (mobile networks) standardized ecosystem and Wi-Fi being Wi-Fi alliance (fixed networks) do not have many convergence points and even though smartphones have had both interfaces for years, moving traffic seamlessly between them was always a challenge. 3GPP Rel16, released in July 2020 defined ATSSS (Access Traffic Steering, Switching, Splitting) functionality, which for the first time promises to solve this problem in an elegant way. BBF has now collaborated with 3GPP in working on joint requirements for converging all mobile and fixed traffic into a single 5G converged core. This resulted in a new BBF TR-470 – 5G Wireless Wireline Convergence Architecture, which adopts the 3GPP convergence architecture based on ATSSS and extends the specification to include requirements on the fixed broadband access network and Customer Premises Equipment (CPE).

Today – The future is defined, but how do we get there?

With 3GPP Rel 16, released in July 2020 and BBF TR-470, released in August 2020, future convergence architecture is somewhat defined, but the question remains: How to get from what we have in the network today to what is defined in those papers?

Existing standards do not offer an answer to this question. It will be some years before network operators have a clear situation in their networks: all required network functions developed, and integrated and legacy services marginalized to the extent that they will not be an obstacle. This waterfall planning model, assuming precisely defined years of development, is surely outdated.

Until that future, in which everything is ready for the converged 5G core network, a smaller industry group is leading the way with a more agile approach. The need for higher bandwidth and more reliable broadband is more important than ever. Last year our lives moved online overnight in an unprecedented transition of work, education, shopping, entertainment, and social life.

With service providers and devices ecosystem partners, Tessares is working on the “missing link” – Overlay ATSSS. Overlay ATSSS enables convergence of fixed and mobile access networks, based on the same underlying technology and concepts used in the above mentioned standardization documents, however its OTT deployment model enables deployment now, without dependency on other 5G core components. The same OTT decoupling from complex integration with other 5G core components, allows for agile development and deployment of features and functionalities.

Tessares “Overlay ATSSS” is currently undergoing initial trials with leading service providers and smartphone manufacturers and the results of those trials will pave the way for the first commercial deployments next year. 

In the fixed broadband domain, the same service architecture from Tessares is already improving the fixed broadband of hundreds of thousands of customers of leading converged service providers across Europe.

Tomorrow – There is no tomorrow chapter, we must write it together.

Those developments will finally unlock the full potential of Hybrid Internet Access bonding and convergence, providing best possible connectivity services using all available access network technologies. Of course, a lot of it is still unknown, but pioneers will pave the way to the converged network future and we will figure out how to get there – together. 

Read more about Tessares Overlay ATSSS solution here: https://www.tessares.net/whitepapers/