5G ATSSS Solution

Turning heterogeneous 5G & Wi-Fi networks into a converged network with ATSSS

1.8 Billion 5G smartphones will be sold in the next 5 years generating 12% of total data traffic¹.

As much of mobile activity is in users’ home, today’s traffic offload to Wi-Fi is more important than cellular traffic. According to Cisco, the gap will continue to widen due to 5G and should reach 71% of offload².

These figures demonstrate the growing importance of both networks (5G & WiFi) intended to coexist. In order to ensure seamless connectivity between these heterogeneous networks, 3GPP has defined in the forthcoming 5G Release 16 a function called ATSSS that manages the 5G & WiFi convergence. 

ATSSS stands for Access Traffic Steering, Switching & Splitting. It will work as a rules engine where operators’ policies can be specified based on business drivers, technical drivers or a combination of both. 

Figure 1: ATSSS capabilities and the benefits for the end-user

3GPP studied more than a dozen of different technical solutions to enable 5G and Wi-Fi to coexist efficiently. After one year of discussion, they have decided in December 2018 to leverage the unique capabilities of Multipath TCP combined with the 0-RTT-Convert protocol, defined by Tessares. Multipath TCP enables smartphones to simultaneously use their Wi-Fi and cellular interfaces. Apple uses it since 2013 to improve the experience of mobile users. Samsung, LG and Huawei also use it in some countries to combine Wi-Fi and 4G. The 0-RTT-Convert protocol enables a smartphone that supports Multipath TCP to use its cellular and Wi-Fi interfaces simultaneously through the ATSSS service without increasing latency.


Tessares’ 5G ATSSS solution

Tessares’ ATSSS solution leverages the experience gained by Tessares in deploying Multipath TCP proxies that support Hybrid Access Networks in different networks that use them to combine xDSL and LTE. Our 5G ATSSS solution is a software package that can be added in virtualised 5G cores. 

Figure 2: ATSSS implementation with Multipath TCP architecture

It is currently being tested in live 5G networks, contact us for additional information on its features.

Read our recent white paper describing the central role MPTCP is playing in 5G standardisation.

(1)– Ericsson Mobility Report (June 2019) – page 7
(2)Cisco VNI White paper – Forecast 2017-2022