Network User's Guide

Security Features
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Internet Key Exchange (IKE)
IKE is a communication protocol used to exchange encryption keys to carry out encrypted communication
using IPsec. To carry out encrypted communication this time only, the encryption algorithm necessary for
IPsec is determined and the encryption keys are shared. For IKE, the encryption keys are exchanged using
the Diffie-Hellman key exchange method, and the encrypted communication that is limited to IKE is carried
out.
If you selected Custom in Use Prefixed Template, select IKEv1, IKEv2, or Manual.
If you selected a setting other than Custom, the IKE, authentication type and Encapsulating Security selected
in Use Prefixed Template are displayed.
Authentication Type
Configure the IKE authentication and encryption.
 Diffie-Hellman Group
This key exchange method allows secret keys to be securely exchanged over an unprotected network.
The Diffie-Hellman key exchange method uses a discrete logarithm problem, not the secret key, to send
and receive the open information generated using a random number and the secret key.
Select Group1, Group2, Group5, or Group14.
 Encryption
Select DES, 3DES, AES-CBC 128, or AES-CBC 256.
 Hash
Select MD5, SHA1, SHA256, SHA384 or SHA512.
 SA Lifetime
Specify the IKE SA lifetime.
Type the time (seconds) and number of kilobytes (KByte).
Encapsulating Security
 Protocol
Select ESP.
NOTE
ESP is a protocol for carrying out encrypted communication using IPsec. ESP encrypts the payload
(communicated contents) and adds additional information. The IP packet consists of the header and the
encrypted payload, which follows the header. In addition to the encrypted data, the IP packet also includes
information regarding the encryption method and encryption key, the authentication data, and so on.
 Encryption
Select DES, 3DES, AES-CBC 128, or AES-CBC 256.
 Hash
Select MD5, SHA1, SHA256, SHA384, or SHA512.
 SA Lifetime
Specify the IPsec SA lifetime.
Type the time (seconds) and number of kilobytes (KByte).