[Winpcap-users] TCP Retransmission

[Guy Harris]

On Oct 24, 2007, at 6:27 PM, Bryan Kadzban wrote:

> Because the sender thought the receiver didn't get it (because the
> sender never got an ACK for those bytes).  See the above-mentioned RFC
> subsection: "If the ACK is not received within a timeout interval, the
> data is retransmitted."

...and note that TCP is a byte stream protocol, not a packet-based  
protocol, so if the sending process has written more data to be sent,  
a retransmission might send not only the previously-transmitted data  
but also data queued after that.  That's probably why the  
retransmission "contains a few more bytes".