Wireless Peer to Peer communication w/o user intervention pairing

RE: Wireless Peer to Peer communication w/o user intervention pairing

ovrebekk — Wed, 29 May 2024 13:42:13 GMT

You welcome Gaurav, the best of luck with your project 🙂

RE: Wireless Peer to Peer communication w/o user intervention pairing

gaurav13r — Tue, 28 May 2024 10:39:47 GMT

[quote userid="2116" url="~/f/nordic-q-a/111267/wireless-peer-to-peer-communication-w-o-user-intervention-pairing/485361"]Why is using OOB a problem? You will need to add an NFC reader on one side, since the nRF device can be NFC tag only, but then you should be able to do secure OOB pairing over BLE without requiring any user interaction. [/quote]

It's an over head, one additional technology to take care.

[quote userid="2116" url="~/f/nordic-q-a/111267/wireless-peer-to-peer-communication-w-o-user-intervention-pairing/485361"]The bitrate of the NFC solution supported by the nRF devices is 106kbps, but I expect there is some overhead as well, meaning the actual data throughput would be lower. In other words you should get significantly better throughput when using the radio. [/quote]

Thanks for sharing that. It helps!

RE: Wireless Peer to Peer communication w/o user intervention pairing

ovrebekk — Wed, 22 May 2024 10:43:55 GMT

Why is using OOB a problem? You will need to add an NFC reader on one side, since the nRF device can be NFC tag only, but then you should be able to do secure OOB pairing over BLE without requiring any user interaction.

You could also do a proprietary RF implementation using a protocol such as ESB, but then you will need to do more work on the firmware side in order to implement the higher layers of the RF protocol.

[quote user="gaurav13r"]I'm wondering if you would suggest using UWB for just P2P communication. If yes, how bad will be the packet loss? Do I need to have my own retransmission protocol on top of UWB link?[/quote]

Not sure what you mean by UWB in this context?
Nordic doesn't provide any UWB solutions, so if you want to explore this you would have to look elsewhere.

[quote user="gaurav13r"]Another thought is NFC, what would be the maximum throughput that can be achieved NFC considering that devices are in direct contact with each other? [/quote]

The bitrate of the NFC solution supported by the nRF devices is 106kbps, but I expect there is some overhead as well, meaning the actual data throughput would be lower. In other words you should get significantly better throughput when using the radio.

Best regards
Torbjørn

RE: Wireless Peer to Peer communication w/o user intervention pairing

gaurav13r — Tue, 21 May 2024 11:32:40 GMT

Hello Torbjørn

[quote userid="2116" url="~/f/nordic-q-a/111267/wireless-peer-to-peer-communication-w-o-user-intervention-pairing/485045"]Will both devices be under your control? Put another way, would you use nRF devices on both sides? [/quote]

Yes, both the devices will be developed in-house and they can be nRF chips as well.

[quote userid="2116" url="~/f/nordic-q-a/111267/wireless-peer-to-peer-communication-w-o-user-intervention-pairing/485045"]What kind of security do you require? Will the communication have to be encrypted, and will an authenticated link be necessary?[/quote]

Since these devices are medical equipment, so security will be required and the data should be encrypted.

The issue with BLE is I need to have OOB implemented as pairing based on UUID or advertised name won't work as there can be multiple peripherals in vicinity and I should be connected to the one that is physically mated with central device. RSSI may help but these devices can be in very close proximity.

I'm wondering if you would suggest using UWB for just P2P communication. If yes, how bad will be the packet loss? Do I need to have my own retransmission protocol on top of UWB link?

Another thought is NFC, what would be the maximum throughput that can be achieved NFC considering that devices are in direct contact with each other?

RE: Wireless Peer to Peer communication w/o user intervention pairing

ovrebekk — Tue, 21 May 2024 10:47:57 GMT

Hi Gaurav

Will both devices be under your control? Put another way, would you use nRF devices on both sides?

What kind of security do you require? Will the communication have to be encrypted, and will an authenticated link be necessary?
In general it is hard to combine little user interaction with a high level of security.

BLE seems to be the best fit based on your requirements. Assuming you control both sides you can set up the central and peripheral to connect and pair automatically, based on whichever criteria you want (such as the advertised name or UUID of the peripheral, RSSI strength, and more).

Best regards
Torbjørn