88                                                                 Internet

               8                 16                                   31
Next Header         Length      |               Reserved

Security Parameters Index

i                               Authentication Data                                i
i                                                                                  i

. 2.26.  -

Next Header (8 ).    .

Length (8 ).  .      -
  32- .      ,
     ( ).

Reserved (16 ).   .

Security Parameters Index (SPI) (32 ).   . -
 ,     SA (
 ,    . .).   0 -
   ,  1255 .

Authentication Data.       -
       (-
    ).    
 (  )    (SPI   ).

    IP,  , 
         
 .  ,    
 ,        -
  IP    .     
   ,      -
 .

    ,    ,  
     "" IP
Encapsulating Security Payload (ESP).      
,   IP .      
 .

 ICMPv6

 ICMPv6   ICMPv4   , 
    IP-:  
ICMPv6,     (Next Header),  
  ICMPv6,     ,
      . .