QUIC network layer: Automatic update and sleep mode

Our development of the QUIC network layer continues, and with 4D 20 R4, we now have the sleep mode and the automatic update. Let’s take a closer look at these enhancements and see how they compare to the way they work with other network layers.

Sleep Mode

Let me start with the sleep mode.

When you put your machine to sleep, 4D enters a state called “sleep mode.” It cuts the connection to the server and instantiates it when you wake your machine up. In the meantime, 4D Server keeps your session open for a specific time (2 days by default), after which it disconnects you. Sleep mode is essential to prevent losing your work when you leave your computer for a short time, for example during the lunch break, and that’s why it is now available with the QUIC network layer.
As a side note, the postpone mechanism (and idle connection timeout) of the ServerNet layer hasn’t been reported to the QUIC network layer as it is not helpful.

Automatic update

I expect many of you to wonder how they will transition their applications to the QUIC network layer. Don’t worry; the automatic update works perfectly with the QUIC network layer. Still, its functioning is a bit tricky, and as such, I want to explain to you exactly how it happens.

QUIC is unique among 4D network layers as it is based on UDP, not TCP. As a result, the interaction between an old 4D client built with a version of 4D that didn’t know about QUIC and a 4D Server running on the QUIC network layer is technically impossible. But fortunately, we have thought about it and made sure it works.

What happens is that even when you run on the QUIC network layer, the 4D Server still accepts TCP connections from 4D clients using the ServerNet layer. These connections can be utilized for update purposes. Actually, they can only be used for update purposes. Once the old 4D client has been updated to the latest version, it will have no issue connecting to the 4D Server using the QUIC network layer.

Stay in touch

I can already tell you that 4D 20 R5 will also bring many new QUIC features. Stay tuned!