Wi-Fi Cellular Convergence

Seamlessly transition between 4G/5G and Wi-Fi for a better user experience.

A smartphone’s user experience is impacted by:

  • Edge-of-network problems →  the phone can stick to a poor wi-fi network
  • Handovers between cellular and Wi-Fi →  app sessions can stall

→ The user disables Wi-Fi, and then remains on cellular sometimes for hours.

Seamless Overlapping Handover enables 4G/5G traffic to transition to/from Wi-Fi without disturbing the user experience.

To achieve this, in 2020 the 3GPP defined the ATSSS feature (Access Traffic Steering Switching & Splitting), based on MPTCP technology, comprising software on the handset and in the network.

MPTCP has been used in Apple handsets since 2013 and Samsung handsets since 2015.

Tessares Enables Seamless Overlapping Handover

Tessares 'Overlay' ATSSS enables the deployment of Seamless Overlapping Handover today.

Tessares Overlay ATSSS combines Wi-Fi with 4G / 5G



A smartphone handset is one component of our solution.

ATSSS is implemented in the OS of the smartphone by the smartphone manufacturer. 

ATSSS Network Node

Hybrid Access Gateway

ATSSS is deployed via a Hybrid Access Gateway.

ATSSS Network Node

Important notes

Smartphones will soon support ATSSS in the OS (ie. without the need for a 3rd party app). The smartphone ATSSS component is responsible for deciding which network paths to open and when.

The Tessares Overlay ATSSS HAG component is based on our field proven hybrid access gateway. The advantage of Overlay ATSSS is that, whereas 3GPP Rel 16 envisages ATSSS in the UPF of the 5G Core, service providers can deploy Tessares’ Overlay ATSSS today for 4G & 5G while waiting for ATSSS/5GC to be delivered.

Seamless Overlapping Handover Benefits

Leverages existing automatic connection to Wi-Fi APs

Improves the UX when stuck to poor Wi-Fi by temporarily compensating with cellular

Avoids app session stalling via seamless overlapping handover between cellular and Wi-Fi

Discourages Wi-Fi switch off

No need for 3rd party apps

Supports 4G, 5G, and CBRS

Prioritises the cheapest network (Wi-Fi)

Ensures the best use of cellular and Wi-Fi networks