Insufficient Encryption Key Size

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Anonymous
Not applicable

So I'd REALLY like to keep my bonding information after an OTA update but invariably I get INSUFFICIENT_ENCRYPTION_KEY_SIZE when I try to pair after OTA.  I assume some key information or bonding data is getting lost. I'd happily save and restore whatever is getting lost but I'm not having any luck there.  I've tried saving and restoring all the key data but apparently I'm not doing this correctly or I'm missing something entirely.  I'd greatly appreciate any help, hints or suggestions.  Thanks in advance!!

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1 Solution
AnjanaM_61
Moderator
Moderator
Moderator
5 comments on KBA First comment on KBA 5 questions asked

Hi Lord master,

   

It is not possible to store bonding data for OTA applications. Because after firmware updgrade the entire flash will get over write, so bonding information will be lost.

   

Thanks,

   

Anjana

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4 Replies
AnjanaM_61
Moderator
Moderator
Moderator
5 comments on KBA First comment on KBA 5 questions asked

Hi Lord master,

   

It is not possible to store bonding data for OTA applications. Because after firmware updgrade the entire flash will get over write, so bonding information will be lost.

   

Thanks,

   

Anjana

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Anonymous
Not applicable

True, flash will be over-written but SFLASH is not affected by OTA. In theory, bonding information could be stored here and will not be affected by OTA.

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Anonymous
Not applicable

In theory perhaps 🙂

   

In practice, the bonding information is stored in the cypress stack (I think), which means that ota updates would affect the location and format possibly, leading to corruption on new/version updates. Plus, you would need to write it back to the same location upon bootup, and do all of the verification/checking that the data is valid, etc. A lot of "hacking" in practice I think.

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Anonymous
Not applicable

In theory, practice and theory are the same.  In practice, they are different.

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