78                          __ ____________________ Internet

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Payload Length (16 ).  .     ( ),
   .      0,  
   65535     Jumbo Payload (-
)  Hop-by-Hop Options (. ).

  IPv4 Total Length     IPv6 
 Payload Length.      ,   -
,   Payload Length     ,
     Total Length   .

Next Header (8 ).   .    -
  ,     IPv6.

      IPv4    Protocol.
    Next Header  IPv6.  IPv4   Protocol,
   TCP  17  UDP, ,   -
    IP-.  IPv6  Next Header -
      IP  TCP 
UDP.      ,   -
   IP-.  ,    Next
Header      ,
  ,      -
 Internet Header Length,  IHL.

Hop Limit (8 ).   .   
  1      . 
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    Time to Live  IPv4  .   -
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   ,       1 -