Re: Standard CAN over IP

[Oliver Hartkopp <socketcan@hartkopp.net>]

On 18.02.2015 18:57, Maximilian Güntner wrote:

> Some features are still missing, like packet loss detection and the
> re-transmission of lost UDP packets. CAN_FD is also not implemented.

Hi Maximilian,

I would suggest to implement CAN FD from the beginning.

When creating the CAN RAW socket just try to switch it into CAN FD mode:

const int canfd_on = 1;

/* try to switch the socket into CAN FD mode */
setsockopt(s, SOL_CAN_RAW, CAN_RAW_FD_FRAMES, &canfd_on, sizeof(canfd_on));

No need to check for the return value here if you are able to handle CAN FD in 
your application.

And do this CAN FD sockopt on the target socket too.
When you are getting CAN FD frames and the target CAN interface only supports 
CAN2.0 the FD frames have to be dropped - people will surely detect this :-)

The only problem will remain how to encapsulate two different frame lengths 
and parse them correctly at the target node.

I wasn't able to get behind your UDP CAN frame encapsulation concept (missing 
C++ knowledge) so you definitely know better than me :-)

Regards,
Oliver