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IPv4 IPSec vs IPv6 IPSec

Currently i am studying IPv6 in depth and here i am confused with notion IPv6 IPSec. May i know what is the Difference between IPv4 IPSec and IPv6 IPSec in terms of functions, implementation and configuration, a brief review?  What is there that IPv4 IPSec dont support or provide comparing to IPv6? Will be grateful for some good reference material.


Hi , Here are the more

Hi ,


Here are the more important features of IPv6 to take in consideration from my perpective.


Two good reasons to move to IPv6 are as follows:


* IPv6 has more address space available.

* We are running out of public IPv4 addresses.


  • Has 128-bit
  • Does not support NAT
  • Use stateless address autoconfiguration to assign an IP add (instead ) DHCP , but also supports DHCP
  • IPsec is “supposed” to be required but not necessary.
  • Simplified but larger IPv6 header
  • Does not use broadcast
  • Does not use ARP, instead use  Neighbor Discovery Protocol (NDP or ND) using ICMPv6
  • Does not use NAT / PAT
  • Use a net mask
Community Member

Dear Ivarelac, Thanks for

Dear Ivarelac,


Thanks for your reply, I have noted down your points for IPv6 and the points you disucssed give reasons why we choose IPv6 over IPv4? I want to explore the difference betweeen IPsec feature between IPv4 version vs IPv6 version. As we know for IPv4 IPsec is add on, where as for IPv6 all details claim that it is built in feature, what confuses me is that both features required mutual agreement and pre-configuration and activation at point A and Point B? 


IPsec is a mandatory

IPsec is a mandatory component for IPv6, and therefore, the IPsec security model is required to be supported for all IPv6 implementations in near future. In IPv6, IPsec is implemented using the AH authentication header and the ESP extension header. Since at the present moment, IPv4 IPsec is available in nearly all client and server OS platforms, the IPSec IPv6 advanced security can be deployed by IT administrators immediately, without changing applications or networks.



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