UDP socket buffer size

[neil]

Hi Mark
  Hope you are keeping well...

Where do I find max buffer size of a received UDP packet?  My application can transmit 1k of data and want to make sure the buffer is large enough to hold this

Best Regards
Neil

[mark]

Hi Neil

As long as the Ethernet Rx buffer can hold the UDP reception it will be adequate - your receive the UDP packet directly in that buffer:

#define LAN_BUFFER_SIZE        1518

is adequate for the largest Ethernet frame (excluding jumbo frames) and so UDP payload (over IPv4) is limited to 1492 bytes (I believe) - this assumes no fragmentation, which will be the case in modern local networks.

Regards

Mark