Border router using nrf5340 and Zephyr

[Hiihtaja]

Hello !

We need to have the border router functionality for 6loWPAN in our device using a nRF5340.

From one side of the device we have USB-NET connectivity to Host to other side - proprietary serialized radio on network core ( 6loWPAN  compatible, require fragments to send and will receive fragments).

It means Ethernet like interface should receive IP packets and if need to route those to serial network interface (6loWPAN fragments in and out).

Can this kind of typical Iot device scheme be assembled from existing Zephyr network components ?

If not, what kind of functionality are missing  or will be implemented in this year releases ?

Regards,

Eugene

[Charlie]

Hi Eugene,

Nordic does not provide general Zephyr project content support, actually, we do not have any resources working on 6lo-related stuff any more.

You can raise an inquiry here Issues · zephyrproject-rtos/zephyr (github.com) to get a reply from the maintainer of zephyr/subsys/net/ip at main · zephyrproject-rtos/zephyr (github.com).

Best regards,

Charlie

[Hiihtaja]

Hi Charlie !

I think 6loWPAN over BLE is out of this question.

In you echo server sample https://developer.nordicsemi.com/nRF_Connect_SDK/doc/latest/zephyr/samples/net/sockets/echo_server/README.html

you offer double network interface support but it is not so  clear what kind of support is given for routing between those 2 interfaces.

With CONFIG_NET_IF_MAX_IPV6_COUNT=2

and 

$ west build --pristine --board nrf5340dk_nrf5340_cpuapp -- -DOVERLAY_CONFIG="overlay-802154.conf;overlay-netusb.conf"

netconsole show

How in this sample IP packets from your IEEE 802.15.4 inteface can be routed to Linux Host via Ethernet interface ?

Regards,

Eugene

[Charlie]

Hi Hiihtaja,

Let me explain the relationship between Nordic nRF Connect SDK(NCS) and the open-source Zephyr project first. NCS use and contribute to the Zephyr project, but we do not own Zephyr. Only the libraries and samples in NCS are specifically maintained by the Nordic development team. The Zephyr and its common samples and libraries are developed under the Zephyr project organisation, they are not specifically adapted for nRF products usage. You should always refer to the content in ncs/nrf, especially samples, which clearly point out which nRF DK it is designed for, so nRF5340DK will not just work with the echo server sample as you expected.

Hiihtaja said:

How in this sample IP packets from your IEEE 802.15.4 inteface can be routed to Linux Host via Ethernet interface ?

This device sounds like OTBR. You can refer to how an OpenThread device communicates with the global network with OTBR. This will need effort on both device and Linux host side, we are not able to guide you on such a big project. Here is the stack of OTBR with RCP and openthread/src/posix at main · openthread/openthread (github.com) running on host mainted by google.

Best regards,

Charlie

[Hiihtaja]

Hi Charlie !

Zephyr's support said that routing is completely disabled in ip stack:

“

Routing functionality in Zephyr is currently "in suspension" I'd say, as it was hidden when RPL support was removed: zephyr/Kconfig at main · zephyrproject-rtos/zephyr Perhaps you could try to enable it and experiment, but you'll likely need to fill the routing table manually, you're on your own here.

“

Regards, Eugene