DFU over Mesh time requirements

[PM Bubblynet]

Just to clarify a bit, I get that the DFU will take ages to propagate though a large network, but the first insertion of the new DFU from, lets say a cellphone, to the "proxy" node might take 1 - 2 hours max then the origin cellphone can disconnect and the DFU will keep spreading through the Mesh?

I don't see a big issue that a DFU of a large network might take few hours, but I hope that the origin node can disappear and its not required to deploy completely the DFU to all the nodes on the Mesh.

[Sigurd]

Hi,

PM Bubblynet said:

lets say a cellphone

I don't think Mesh DFU from phone is supported. 

PM Bubblynet said:

can disconnect and the DFU will keep spreading through the Mesh?

PM Bubblynet said:

but I hope that the origin node can disappear and its not required to deploy completely the DFU to all the nodes on the Mesh.

No, that is unfortunately not supported. The DFU master has to be connected the whole time.

[PM Bubblynet]

Hi Signud,

Thanks for the answer, the question was not so much to whats supported at the moment, rather of how the DFU is supposed to work, for example:https://devzone.nordicsemi.com/f/nordic-q-a/36316/bluetooth-mesh-dfu-by-nordic-mobile-app-libraries its mentioned that: 

"the idea is the DFU gateway node (the node that " stores these packets, and also forwards .." ) should be able to talk to a phone as a gatt proxy. Then the phone send the image to the gateway node and the image be distributed to the mesh network."

[Sigurd]

Hi,

PM Bubblynet said:

rather of how the DFU is supposed to work, for example

The idea described in that post is in theory possible. And implementing a DFU master for the proxy node, the phone could in theory disconnect after it has sent the fw image, and the proxy node/DFU master would be responsible for the deployment. But it's not implemented or supported today, so this is all just hypotheticals at the moment.

[PM Bubblynet]

Hi! I see, is there any technical specification / requirements from SIG regarding this? I am rather looking at this from a system design / roadmap point of view... rather than being limited by what's implemented / supported at the moment, it would be nice to know how supposed will be implemented in the future according to specifications or requirements either from SIG or nRF connect or Mesh SDK etc...

[Sigurd]

PM Bubblynet said:

is there any technical specification / requirements from SIG regarding this?

 No. The current Mesh spec does not include anything about Mesh DFU, or how it should be implemented. The DFU solution in the Mesh SDK is therefore Nordic proprietary. You can read more about the current Nordic Semiconductor Mesh DFU protocol here and here.