Re: [lwip-users] Sending a large amount of data using UDP

[Patrick Klos]

On 7/19/2020 6:44 AM, Jon Bean wrote:
> Hi
>
> I have an application were I need to send around 4k of data using UDP. 
> What I would like to know is how I go about sending this using LWIP. I 
> can send small packets no problem. I first allocate a pbuf. Then copy 
> my data to the pbuf. Then send the data. But sending 4k of data doesnt 
> work. I realise that the Ethernet has a max payload of 1500 bytes. Is 
> there a different way to send large amounts of data? Do I need to 
> configure something and then do it the same way I have previously? I 
> am using a embedded TIVA micro controller.
>
> Thanks
>
> Jon

Have you enabled IP fragmentation? (IP_FRAG)

Or you could just break up the data yourself, add a little custom 
header, and essentially fragment the data yourself.  Depending on what's 
in this data, you could add sequence numbers and a way for the peer to 
report they missed a chunk?  How often are you sending these blocks of data?

Patrick