Notizen:
IPsec Security Associations can be used in one of two different modes: Transport and Tunnel Mode.
TheTransport Mode is used when two single parties want to exchange their traffic encrypted.
Tunnel mode is used when both parties using the IPsec Security Association are gateways which encrypt the traffic of networks connected to them.
To achieve Tunnel mode the packets passed between the networks are encapsulated using IPsec between the gateways.