IP
security is a technology that operates the two modes: transport and tunnel
modes. Each of these modes has its own uses and care should be taken to ensure
that the correct one is selected for the solution.
·
Tunnel mode is most very often used between gateways, or at
an end-station to a gateway, the gateway temporarily doing the duties as a
proxy for the hosts in support of it.
·
Transport mode is used between
end-stations or between an end-station and a gateway, if the gateway is being
treated as a host—for example, an encrypted Telnet session from a workstation
to a router, in which the router is the actual destination.
