Extension_IP_Header

擴充的 IP 標頭

Preface for Basic Network

see https://github.com/QueenieCplusplus/Networking

IPv6 Header

Header looks like

      IPv6 Header            |
      Next Header = TCP      |     TCP Header & Data
      Value 6                |

Header Fields & holding space

    Version 6

    Traffic Class (Procendence)

    Flow Label (to make flag on sequence)

    Payload Length

    Next Header (the extension header, the topic we discuss hereby)

    Hop Limit, 中繼

    Src Addr

    Des Addr

Drop Header, return

    A Msg shows ICMPv6 Param Problem

Extension Header

• Encapsulation Sec Payload Header

• Auth Header

• Routing Header

    有欄位稱為 Segemt Left, 能顯示還有多少節點需要拜訪
  

• Hop-by-Hop Options Header

AH, Auth Header

AH Fileds

• Next Header = Auth Header

• Reserverd

• SPI, Security Param Index

• Payload Data

• Seq num

• Checksum

ESP, Encapsulation Security Payload Header

Features:

(1) anti-replay

(2) auth

(3) confidence

(4) integrity

ESP Fields

• SPI

• Payload Data (Encypted Data)

• Seq num

• Next Header = Auth Header

• Auth Data

Combination of Auth & ESP

(talk later)

Tech for Trans/Rcv

• 4 & 6 Dual Stack

• Tunneling

  https://www.wikiwand.com/en/Layer_2_Tunneling_Protocol

• 4To6

(to be continued...)

Tunneling