When switching from one WiFi to another, how come it shuts off the internet while switching, and can’t pass it over without an interruption?

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When switching from one WiFi to another, how come it shuts off the internet while switching, and can’t pass it over without an interruption?

In: Technology

I’m guessing it’s because the device can only be connected to one network at a time. To have a seamless switch, it would have to be possible to be connected to 2 at a time.

That’s because your device has to “prep” a lot of configurations such as encryption keys, protocols etc.
Think of it as switching the battery in your car, you first gotta unplug it, check which wire goes well, reassure you did it correctly and then proceed to turn your car on. It took you time to do all that, you really can’t just instantly switch the power supply of your car.

Back in the days of dialup, I had a PPP client that could suspend and resume network traffic in that way.

But switching WiFi networks is like switching houses: everyone needs to know the new address, and you need a key to get in.

So any established sessions are going to drop; the truck is that it’s technically possible to buffer your side of the connection and re-send the last requests made through the new address, but no OS does that anymore, partly because it’s hard to do well, and partly because it’s hard to do securely.

It can, but your WiFi network has to support ‘roaming’.

Think of a small WiFi network with a single access point as a delivery person who delivers lots of small packages for you. Before they will deliver however, they insist you fill out and sign a form to make sure you are who you say you are and agree to some things such as how fast you are going to be sending packages and how you are going to wrap them. They insist that you go through this process every time you start talking to them and deliveries won’t start until they are happy.

You add another delivery person to extend the range of the deliveries, but they insist on going through their own form every time you talk to them. They might have extra questions if they work for a different company. If you constantly switch between delivery people there can be a lot of paperwork involved.

Corporate WiFi if correctly set up for ‘roaming’ will hire lots of delivery people from the same company who are prepared for you to keep switching and will only make you fill out one form at the start which they share with each other without bothering you.

Imagine it like this – you change your home address, what happens with the letters sent to you? Some are still sent to your old address and then returned because you’re no longer there. Meanwhile you wait for them at your new home, don’t get them, update address and ask the sender to send them again. That’s why there is an interruption