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Comment by breppp

19 hours ago

I don't know how practical but I always thought of extending the Wifi protocol with a clock broadcast

That way all the microwaves of the world could listen in and update their clocks accordingly

Apparently at least Bluetooth has something called Current Time Service (CTS) (BLE GATT service 0x1805). If you pair a cheap "smartband" to a phone, it'll set itself, even without using any apps. Neat! I guess it uses CTS?

Nokia proposed using SIB9 5G time transmission as time syncing in clocks, the idea being that transmission is available openly even for non-subscriber. Softbank later proposed commercializing the service, which is unclear to me since surely the public transmission would be enough for casual users and anyone requiring more would already use full 5G to control the device anyway.

Why bloat Wi-Fi with a clock signal when we already have a perfectly cromulent network time protocol?

  • I assume you don't need to implement a full network stack just to read a discovery packet and it would be easy to add to future wifi routers

But how do you make it secure? Add a signature with a fixed key?

  • The issue is which time signature do you trust without selecting an SSID, maybe by power? But I agree this can be an issue albeit small one in my opinion