It has been a long time since the DCC protocol was last discussed, so if you were there during those discussions, please correct me if I am wrong. As I remember it, the issue linked to above is actually possible with DCC Send. DCC Send simply allocates a port number to which a receiver can connect to receive a transfer. This means that if a send fails/times out/is cancelled and its port is allocated to another send, the receiver can connect to that port thinking that it is related to a different send request. If the DCC Send protocol allowed for the first few bytes of the transfer to include identifying information, that would prevent an issue like this but it was not so designed.
