BLE 4.2 reading Characteristic

RE: BLE 4.2 reading Characteristic

FormerMember — Fri, 31 Mar 2017 10:32:21 GMT

Could you do the sniffing again? I can only see advertising packets in the sniffer log..

RE: BLE 4.2 reading Characteristic

Moussa Aw — Thu, 30 Mar 2017 07:32:46 GMT

Actually, the attached trace is in fact without any filtering. This can be observed by the different devices present in the trace. What I meant was the above 2 filters mentioned can be applied to the trace so that you can detect the packets that correspond to the device the phone is connecting to.

RE: BLE 4.2 reading Characteristic

FormerMember — Mon, 27 Mar 2017 09:05:10 GMT

The sniffer trace does only show the advertising packets. In wireshark, could you do the sniffing without using any filters?

The stored bonding information is encryption information. When re-connecting to a bonded device, it is not necessary to share encryption keys to obtain a secure link, because the two devices in the link already have the necessary encryption information.

RE: BLE 4.2 reading Characteristic

Moussa Aw — Thu, 23 Mar 2017 15:01:25 GMT

Hi Kristin,

Finally found an nRF51-DK and installed the recommended sniffer along with its wireshark extension. This is the trace to what was transferred over the air trace.pcapng.

The nRF51422 address is: "ff:dc:75:a2:db:ac" and its public name is "Pay". I used these filters on wireshark:

btle.adv_addr==ff:dc:75:a2:db:ac
btle.128b_uuid==a6:5e:bb:2d:3d:30:49:81:9d:b2:19:96:d8:81:18:a0

Could not really observe what you suggested or the packets that correspond to whats happening the second time the Android phone connects to the nRF51422. Maybe you can better interpret and observe what's happening.

Regarding "bonding information", it seems that nRF51422 stores these info. But my question here is that what exactly these info correspond to? Is it a good practice that we delete the bonding information from the central (Available on Android not on IOS). Also if these info should be deleted from the peripheral side, should that be before connecting to the device?

Your answer is highly appreciated, Thank you.

RE: BLE 4.2 reading Characteristic

FormerMember — Thu, 16 Mar 2017 12:29:10 GMT

Does your nRF51422 device store the bonding information, or is the bonding information deleted upon a disconnect?

Do you have an extra nRF51-DK or a nRF51-Dongle? If so, could you use the sniffer to track what is being transferred over the air the second time the Android phone connects to the nRF51422? And upload the sniffer trace here?

The sniffer should be used with Wireshark, and it works best with version 1.10, not one of the newer versions. Wireshark can be downloaded here: