David,
1)Increased capacity, 2) increased coverage and 3) increased
reliability.
Let’s assume for simplicity an user which would be charged for the
amount of data he/she would use over a cellular network using
licensed spectrum while for all the data exchanged over the WiFi.
While the user is under a good WiFi coverage all his traffic is
going to be routed over the WiFi, no data traffic is going over the
cellular. However, when the user is in an area of limited coverage
or the level of interference reaches a certain threshold the quality
of the communication over the WiFi access degrades. As a result the
achievable throughput over the WiFi may get below a certain
threshold. At this moment the WiFi access may not be able to sustain
the throughput the user may require. The user may either switch over
to the cellular (paying a higher penalty) or use both accesses, WiFi
and cellular. When both accesses are used, all the traffic below a
maximum threshold will go over the WiFi access, while all the
leftover traffic will go over the cellular access.
Thank you - this is exactly the kind of user benefit I was asking for.
In other words: the user can save on monetary costs when watching a high
quality video in this very precise scenario of functional but slow Wi-Fi
while in range of high speed but expensive cellular. We can debate how
common this scenario is and how impactful the solution would be, but I
agree that this is an actual end-user benefit.
Today, most of the WiFi networks that the user can access are:
- home Wi-Fi where he/she has manually added a WPA/WEP key
- enterprise/school WiFi that rely on 802.1x or similar technologies
In addition to these two isolated WiFi networks, there ongoing
deployments of roaming solutions that will allow the users to
automatically access millions of WiFi access points.
Those who are part of the academic community know eduroam (see RFC7593)
that basically enables any student to use with his/her credentials the
WiFi network of any university network throughout the world.
Several network operators have deployed authentication techniques that
enable their customers to be authenticated in any of the WiFi access
points that they have deployed in homes and in various locations like
shopping malls, train stations, ...
In parallel, there are efforts to enable users to roam from one of these
managed WiFi network to another. The openroaming initiative (
https://wballiance.com/openroaming/ ) is one example of these solutions.
With WiFi roaming, each user will be able to potentially access millions
of WiFi access points. These WiFi access points will provide very
different an unpredictable performance compared to a fully managed
cellular network. With ATSSS, users will be able to use the roaming WiFi
networks when they work well and automatically offload/switch to
cellular when their performance is not sufficient.
We've all experienced the situation of been connected to a WiFi network
in a pub and then need to manually disable WiFi to force the utilisation
of the cellular network between the pub's DSL link is currently
overloaded. ATSSS would make this seamless for the enduser for all
applications and will also allow to use the WiFi network for part of the
traffic which will be beneficial for the user's bill.
I expect that this scenario will be very common
Olivier
