CODEWITHSUNDEEP
linuxusbcoaplibcoap
add
add

Reputation: 21

How to communicate using libcoap over USB in linux?

I would like to communicate over USB using COAP protocol.

I am currently planning to use libcoap, it has examples but it is based on UDP server-client.

If I want to use USB, what must be done?

Thanks

Upvotes: 1

Views: 363

Answers (1)

chrysn
chrysn

Reputation: 938

Depends a bit on the deployment scenario, but in general I'd recommend using USB Ethernet inbetween (CDC-ECM). Then you can use CoAP over USB like you use it over any other network connection. (If you use RIOT for your embedded device and build the gcoap example on a board with native USB and enable the usbus_cdc_ecm module, you get that almost out of the box).

The large downside of this approach is that you are subject to the whims of the host OS's network setup. Probably it'll take up at least the IPv6 link-local interface so you can go ahead with requests to fe80::addr:ess (or even use link-local multicast to find your device), but there may be pitfalls.

There is the slipmux proposal which would do CoAP over serial, but a) I don't know implementations thereof, and b) it leaves you with similar issues of how to make sure your application can really find the right serial port.

It wouldn't be impossible to specify CoAP over custom USB commands (which would then be taken up by an application), but there'd need to be really good reasons not to just go through USB networking to justify them, and I'm not sure that the complexity of ensuring that your NetworkManager is set up correctly counts.

Upvotes: 1

Related Questions