CCSP SECUR Exam Cram 2 (642-501)

The Router MC supports )only specific tunneling technologies. The tunneling technologies supported are IPSec, IPSec with GRE, and IPSec with GRE over Frame Relay.

• IPSec ” IPSec is the standard configuration you have seen in previous chapters using an IKE tunnel and an IPSec tunnel.

• IPSec with GRE ” IPSec handles only IP traffic. To support non-IP traffic with IPSec, the non-IP traffic must be encapsulated within an IP packet. The Router MC supports IPSec for non-IP traffic by using GRE tunnels with IPSec tunnels.

• IPSec with GRE over a Frame Relay ” IPSec with GRE over a Frame Relay is exactly like IPSec with GRE. However, the Router MC also supports this type of tunneling technology over Frame Relay hub and spoke networks.

Differences Between IPSec and IPSec with GRE

Besides only supporting IP traffic, there are some key differences between IPSec tunnels and IPSec with GRE tunnels. IPSec-only tunnels support dynamic tunneling in addition to providing finer traffic granularity through extended ACLs. However, IPSec with GRE tunnels support spoke-to-spoke connectivity and higher tunnel resilience through the use of routing protocols.