当UDP头校验和不正确时，UDP包是否被丢弃？

Question

如果我打开一个原始套接字，并发送带有错误校验和的udp数据包，那么数据包是否会被tcp / ip堆栈丢弃？

Answer 1

Yes they would be dropped. If you need more reliable communication you're much better off using TCP.

for more information, take a look at this: http://www.diffen.com/difference/TCP_vs_UDP

UDP there's no guarantee that the packets will even be sent, let alone received. If they are in fact received though, they are checked. If they fail checksum they are dropped.

EDIT: also to add to that, udp does not by default order the packets as they are sent, that has to be done at the application level. Bear this in mind if you still intend on using UDP.

Answer 2

If comes packet with wrong checksum, OS will drop it before passing it to the socket.

Destination application cannot determine if packet was lost or comes with wrong checksum. I think that it also cannot force else behavior.