how to connect to the mesh quickly with NFC

[zhengrui]

i created a mesh network using light_demo in NRF52832SDK and  i need to scan a new device to make it join my mesh network .when there are a number of devices and i have to reduce the time to scan these new devices ,so i want to use NFC to complete it. can you give me some help and tell me how to change the codes in provisioner  and server/client?

thanks for any help.

[Edvin]

Hello,

In order to provision using NFC, you would need to have one active NFC scanner. The NFC tags on the nRFs are only the passive NFC part, so two nRFs can't communicate with one another via the NFC. You would need a phone or something to do that.

 

If you are interested, there is a prototype library for iOS for Mesh provisioning, which you can find here. Unfortunately, iOS is very uncomplicated when it comes to accessing the NFC, and we don't have anything on Android and mesh provisioning at the moment, as far as I am aware of.

 

Best regards,

Edvin

[Edvin]

I found this post from Apple. I am not sure where they stand on the NFC part at the moment. Maybe they have opened it up for app-developers. At least it seems like it from that link.

 

However, you need an active NFC scanner to use the NFC tag on the nRF. Either a phone, or an external device that you can connect to the provisioning nRF via some peripheral.

 

BR,

Edvin

[Edvin]

You can use the phone as an NFC provisioner, but you can not scan another NFC tag with the nRF's NFC antenna. 

BR,

Edvin

[zhengrui]

thanks for your reply ,Edvin.

[zhengrui]

Hello,

I think  I have a incomplete expresssion that make you confusion, there is another board with the additional  NFC aerial (not in the nRF) just like RUUVI,and I want to use it to connect to the provisioner(the same board).

[zhengrui]

and if the nRF don't use NFC to connect with provisioner ,what't the method of Static OOB  is used in the light switch demo?maybe this is the confusion that i can't understand.

[Edvin]

What is NFC areial? Is it NFC antenna? (see this).

 

The RUUVI is a device using an nRF52832. It has the passive NFC, just like the nRF52 DK. 

 

It may be that we don't completely understand each other, but what I am trying to say is that the NFC on the nRF is a passive NFC tag. (See this link). Sort of like when you have any sort of cable that has a male and a female contact, you can't connect the male contact to another male contact. 

Equally, NFC has active and passive NFC devices. A connection via NFC requires at least one of the parts to be active, as described in the link above. Two passive NFC antennas can't communicate, because none of them will generate the magnetic field which the antenna uses. Only active NFC devices generate this field.

 

Read the article in the last link.

 

Best regards,

Edvin

[zhengrui]

yes it is NFC-A tag antenna,and can I use it to complete the OOB authentication on RUUVI?

[Edvin]

Both the RUUVI and the nRF has NFC -A tag.

Please see this case.

 

BR,

Edvin

[zhengrui]

Thanks,I have read the case and the NFC can't  communicate with each other as it said even I  add a NFC antenna. It just can be a tag to be scanned and can't be a source scanner.Is that right?Maybe I have a misunderstanding for NFC.

And as I asked before ,the static OOB doesn't real use the OOB method in authentication and it still use the frequency of bluetooth about 2.4G. 

And what's  the other methods to connect to mesh/provisioner except using NFC?

Will you reply me for these questions?

BR,

Zhengrui  

[Edvin]

In the lightswitch example, the key is static, and it is found in provisioner_helper.c in the light_switch_provisioner_nrfXXXX_xxAA example.

It is possible to do this static, but that is an optional step. Static keys are typically programmed during production, but it is possible to do this dynamically. That step is called Authentication, and is optional during the provisioning process.

 

Best regards,

Edvin

[zhengrui]

yes,I get it and I found the definition/value of the key ,the Static "OOB" make me misunderstand.

Thanks.

Zhengrui.