If I'm not mistaken, both S110 and S130 support OTA DFU right?
I understand that nordic semi most likely recommend S130 over S110, but please understand that
my current project works on S110, migrating to S130 could be a bit of a drag. Is there any more compelling reason
that I should use S130 over S110 for OTA? I've successfully tested the OTA on S130, but got cold feet when
thinking about the potention trouble of migration.
Hi,
In the top of the tutorial you linked there is a statment which sums up the situation a bit: "The Secure DFU is the new DFU bootloader provided from nRF5 SDK v12. The old bootloader in SDKv11 and earlier is now called Legacy DFU. Secure DFU is not backward compatible with Legacy DFU." This means that this tutorial and many of the concepts discussed in it does not apply to your implementation. With SDK12 we introduced the rewritten Secure DFU, but the legacy DFU is still the correct choice for projects running on older SDKs and/or SoftDevices. As long as an attacker is not able to connect to the device, there is no security risk. If the device uses a unique passkey, a connect button, or some similar scheme which requires physical access the security offered by BLE holds up.
The combination you are describing is not a problem. I did a quick test and took some screenshots showing me adding a SoftDevice and bootloader to the device and the adding an application though DFU and connecting to it:
Step 1: Flash the S110 SoftDevice to a blank device.
Step 2: Compile and flash the bootloader
Step 3: Add an application over the air using the most recent nRF Toolbox for Android.
Our Android application support both the legacy DFU and the Secure DFU. The two implementations use different UUIDs, so the Android application can determine which protocol to use.
Hi,
In the top of the tutorial you linked there is a statment which sums up the situation a bit: "The Secure DFU is the new DFU bootloader provided from nRF5 SDK v12. The old bootloader in SDKv11 and earlier is now called Legacy DFU. Secure DFU is not backward compatible with Legacy DFU." This means that this tutorial and many of the concepts discussed in it does not apply to your implementation. With SDK12 we introduced the rewritten Secure DFU, but the legacy DFU is still the correct choice for projects running on older SDKs and/or SoftDevices. As long as an attacker is not able to connect to the device, there is no security risk. If the device uses a unique passkey, a connect button, or some similar scheme which requires physical access the security offered by BLE holds up.
The combination you are describing is not a problem. I did a quick test and took some screenshots showing me adding a SoftDevice and bootloader to the device and the adding an application though DFU and connecting to it:
Step 1: Flash the S110 SoftDevice to a blank device.
Step 2: Compile and flash the bootloader
Step 3: Add an application over the air using the most recent nRF Toolbox for Android.
Our Android application support both the legacy DFU and the Secure DFU. The two implementations use different UUIDs, so the Android application can determine which protocol to use.
