IPsec, Internet Protocol Security

IPsec is more reliable than older protocols that only placed security at the application layer of network communication. IPsec is very useful when implementing virtual private networks. It also comes in handy for remote user access via dial-up connection to specific networks. One of it’s biggest advantages is the fact that security configurations can be made without required changes to the computer of an individual user. IPsec gives two options of security service: AH (Authentication Header) and ESP (Encapsulating Security Payload). AH allows authentication to the party sending data - ESP supports the authentication of the sender along with the encryption of the data. The data associated with these services is inserted into a packet header that trails the IP packet header. Different key protocols can be used with IPsec such as ISAKMP or Oakley protocol. Cisco has been pushing hard for the standardization of IPsec. Cisco has since included support for IPsec in it’s network routers.