Say I have a data of 5000 bytes. Once it reaches layer 4 the TCP header will be added. as the data is large there will be 4 pieces of the data; so there will be 4 TCP headers one for each piece. Now the 4 pieces go to the layer 3 one by one. Will there be any function of Fragment Offset and Fragment Bit. Why or Why not?
Now the packets after going through the remaining layers leave the computer and reach the default Gateway. Here both the LAN and the wan interface will have option to set the no of bytes which it could handle which could be same or different from each other.
Now the WAN interface of the gateway supports only 1000 bytes. So there will be further division on the four pieces.
Lets take only the first piece. Currently it has data + TCP header + IP header + IP header + ethernet header. Say if we break it then how are the headers realigned. The gateway might add new ethernet headers and multiple IP headers but there is only one TCP header. So if we have divided the first piece then with which smaller part does the TCP header go.
Please let me know if there is any basic fault in this question. If the question is alright then please let me know the answer or else some links where I can get the answer.