Re: [lwip-users] RE: How to send a large (over 1500 bytes) data one time ?

[Mark Phillips]

Each UDP packet is a complete message, and is sent without
fragmentation, reassembly, confirmation, or re-transmission.

Therefore, a UDP packet must be smaller (or the same size) as the
smallest MTU on the path it's transferred on.

This isn't a property of lwIP, it's a fundamental property of UDP.

You could try increasing lwIP's MTU size, but there's no guarantee that
the recipient (or the routers in between) will handle it.  In general,
if you're going larger than 1500 bytes, you do so at great peril, AFAIK.



PAUL.YU 喻浦軒 wrote:
> Hi Bill,
> 
> Why UDP cannot send large packet ?
> Lwip should do fragmentation/reassembly packet in IP layer, is that right?
> 
> Thank you
> 
> *************************************************************************************************************************
> This email message, including any attachments, is for the sole use of the 
> intended recipient(s) and may contain confidential and privileged 
> information. Any unauthorized review, use, disclosure or distribution is 
> prohibited. If you are not the intended recipient, please contact the sender 
> by reply e-mail and destroy all copies of the original message. [Delta 
> Electronic, INC. Taiwan]
> *************************************************************************************************************************
> 
> 
> _______________________________________________
> lwip-users mailing list
> address@hidden
> http://lists.nongnu.org/mailman/listinfo/lwip-users
>