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Electrical Engineering/TCP/IP and UDP Port Numbers Nomenclature.


Dear Prof Cleggsan

1. As we see port numbers 4, 6, 8, 10, 12, 14, 16, 26, 40 ....
were kept as Unassigned, would like to know the reason for the same i.e. why those numbers were skipped ?.

2. If a new TCP/IP OR UDP Application or Service or protocol is designed and developed, Can we use these above Unassigned ports ?.

3. As we see the Maximum port number value is 61000, so If a new TCP/IP OR UDP Application or Service or protocol is designed and developed, Should we use 61001 as the port number ?.   

Thanks & Regards,
Prashant S Akerkar

Don't know the answer to this question.

But, I believe the answer lies in this web page:

It says these unassigned numbers are due to potential threats but are being used in some cases by special users.  Please refer to the explanations outlined in the portfinder above.

That's all I can offer. If you need more, please refer your question to allexperts in computer software systems.  

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