Here is what happened to my phone a week ago. It's a Samsung Galaxy A52 5G that is less than 3 years old. It's had its problems in the past (screen and battery replacements). Last week, it suddenly froze on me and then kept trying to reboot itself. The reboot attempt kept going through a loop (freeze > reboot attempt > freeze > reboot attempt and so on....). For nearly 2 days, I had no control. Couldn't even turn it off.

Then, all of a sudden, it finally came back on. But, all my contacts and pictures were wiped out. And most apps were gone. To top it off, I can no longer turn on Wi-Fi or my hot spot, but I have no problem accessing the internet. At work, where previously internet access via employer's Wi-Fi was blocked, and I had to use my hot spot to get on, but now I'm on without Wi-Fi or my hot spot being on. So, I'm confused.

Cell data?

I regularly turn my wifi off before leaving for the day so I don't have to deal with the weak wifi signal when running Waze before I set off.

A phone can access internet either via cellular data or WiFi.

“Hotspot” refers to using your phone as a WiFi router of sorts to connect another device to the internet using your cellular data.

Think of it this way:

1. Cellular data goes to/from your phone
2. A computer or tablet without cellular data is linked to your phone via a WiFi connection between your phone and tablet/computer
3. Internet downloads/uploads from the tablet/computer go to your phone via the WiFi connection
4. Your phone forwards those downloads/uploads to the internet via its cellular connection.

The phone’s WiFi needs to be “On” for the hotspot to work.

Cellular data via your phone’s cell plan.

A hot spot is a Wi-Fi signal that your phone generates so you can connect other non cellular devices to, for internet access via your phone's cellular data. The hot spot doesn’t do anything for your phone’s connectivity.

Yes, cellular data. The cellular infrastructure supports multiple styles of data transfer, some of which are digital, maybe even IP (Internet Protocol), and thus able to carry web, e-mail, etc. traffic on TCP. Not that that necessarily needs to be the case, there are other WAN protocols that they could be using, but the wealth of available TCP/IP applications and software base argues for its use in pretty much all cases.

In most cases these days, I suspect TCP/IP is used to carry voice as well via SIP or some other VoIP technology. This is also used for so-called "WiFi calling."

A "hot spot" on a cell phone simply provides a WiFi access point the uses another "channel" for its upstream, perhaps a 4G LTE or 5G cellular signal.

Or maybe they're bouncing lasers off the moon, who knows? :-)

One thing one must keep in mind when trying to understand this stuff is that the mobile providers do their very best to mislead and confuse terminologies to their consumer base. Enough so that, at times, it could be considered lying. Researchers and developers mostly try to use definite and precise language as well as standardization where possible to reduce confusion and misunderstanding. So it is important not to mix and obfuscate terminologies.

An example is when a provider conflates 5G (fifth generation, a mobile telecommunications standard) and 5G Internet (a data transmission speed with no formal definition, but which usually describes a 2x "bonded" 2.5G Ethernet).

And, oh yeah, just because your control screen says that your WiFi is "off," it may not necessarily be so. After all, the phone provider lies about your microphone not always being on, what keeps them from lying about this too?

I'm sure Claude Shannon will be rolling over in his grave for some time!

quote:

Originally posted by architect:

I'm sure Claude Shannon will be rolling over in his grave for some time!

Wow! I haven't heard that name for a long time.

I worked at Bell Labs during part of his tenure there. His Master’s thesis, A Symbolic Analysis of Relay and Switching Circuits, which used Boolean algebra to establish the theoretical underpinnings of digital circuits, was one of our "text books."