Size of empty UDP and TCP packet?

Question

What is the size of an empty UDP datagram? And that of an empty TCP packet?

I can only find info about the MTU, but I want to know what is the \"base\" size of these

Answer 1

If you intend to calculate the bandwidth consumption and relate them to the maximum rate of your network (like 1Gb/s or 10Gb/s), it is necessary, as pointed out by Useless, to add the Ethernet framing overhead at layer 1 to the numbers calculated by Felix and others, namely

• 7 bytes preamble
• 1 byte start-of-frame delimiter
• 12 bytes interpacket gap

i.e. a total of 20 more bytes consumed per packet.