588 CHAPTER 41: CONFIGURING IKE
Figure 176 Diagram of relationship between IKE and IPSec
IKE features Avoid specifying manually all IPSec security parameters in password mapping of
both communication ends.
Allow specifying the lifetime of IPSec SA
Allow exchanging ciphering key during IPSec session
Can provide anti-replay service by IPSec
Allow manageable and scalable IPSec to implement certificate authorization
support.
Allow dynamic end-to-end authentication.
Configuring IKE IKE configuration includes:
Creating an IKE Security Policy
Selecting an Encryption Algorithm
Selecting an Authentication Algorithm
Configuring Pre-shared Key
Selecting the Hashing Algorithm
Selecting DH Group ID
Setting the Lifetime of IKE Association SA
Configuring IKE Keepalive Timer
Creating an IKE Security
Policy IKE negotiation determines whether IKE policies at both ends are matched and
then reach a negotiation using an IKE policy. During the subsequent negotiation,
the security data provided by this IKE policy will be used to protect negotiation
data.
Multiple policies with priority must be created on each terminal to ensure that at
least one policy can match that of the remote terminal.
Encryption algorithm: At present, it includes 56-bit DES-CBC (DES-Cipher Block
Chaining) algorithm and 168-bit 3DES-CBC algorithm.
TCP/UD
P
IPSec
IKEIKE
IPSec
TCP/UDP SA SA
SA negotiation
Encrypted IP message
IP
Router B
Router A