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Does an EIM-NAT work across both UDP and TCP?

Last updated on December 27, 2018

        I've read RFC 4787, 5382 and 5128 and I just need a bit of clarification.
Assume a NAT has Endpoint Independent Mapping behavior for both UDP and TCP. Although I understand that if a machine would send a UDP datagram to one destination and port and then send another UDP datagram to a different destination and port, it would get the same mapping for both (assuming it sent those UDP packets from the same port number), I am unsure of how the NAT would behave if the protocols being used are different for these two different destinations. In other words, if a machine assigned the source port number 7000 to any layer-4 datagram it sends out, and it starts off by sending a UDP datagram to some destination Y1:y1 (IP:port) and then sends a TCP segment to some destination Y2:y2, where Y1:y1 != Y2:y2, would the NAT mapped port number for the UDP datagram end up being the same actual number as the NAT mapped number for the TCP segment?

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