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Overhead with PPP and Ethernet

What is the overhead of transmitting PPP and Ethernet 5000 bytes?

Frame Size for Point-to-Point Protocol : 8 bytes MTU: 500 bytes

Frame size for Ethernet: 18 bytes MTU: 1500 bytes

Both send 5,000 bytes.

I know that this is just a calculation, but I'm not sure how to do it. I can not find it anywhere. I think that since the PPP frame occupies 8 bytes and the maximum transmission unit is 500, then it can send (500 - 8) bytes of information at a time. It sends 10 frames, resulting in 4920 bytes being sent. Then it sends the final (80 + 8) byte with the last frame.

Similarly for Ethernet. (1500 - 18) bytes with each frame. 3 frames sent - 4446 bytes sent. Sending (554 + 18) bytes in the last frame.

This, obviously, does not answer the "overhead" questions. Does anyone have any idea?

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It depends on how you determine the overhead. This answer will involve overhead - this is the number of bytes that must be transmitted in addition to the data itself.

Ethernet, , 5000 IP + TCP/UDP, 18 . , MTU 1500 1482 . 5000 , 4 , 72 (18 * 4). , , , IP-, TCP.

PPP, , 492 . 88 (11 * 8) - , .

, , . , Ethernet, IPv4, UDP, 28 , , (20 IPv4 8 UDP, IP-). Ethernet, , 1454 , , , 4 ( 4- ) 144 .

( , ).

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Source: https://habr.com/ru/post/1716157/

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