Nortel BSG12aw 1.0, Руководство по настройке

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VPN advanced configuration 175
Configuration Guide
Encryption Select the IPSec Encryption. Select one of the following options:
• null - traffic is not encrypted.
• Data Encryption Standard (DES) – a standard for encrypting data that
uses a 64 bit key to encrypt data, but only 56 bits are used. This
standard is considered inadequate for data protection.
• Triple Data Encryption Standard (3DES) – processes each block of
data using a different key each time, resulting in a significantly more
secure message.
• Advanced Encryption Standard (AES128, AES192, AES256) – has a
fixed block size of 128 bits and a key size of 128, 192 or 256 bits. Due
to the fixed block size of 128 bits, AES operates on a 4x4 array of
bytes.
Select DES if you require network speed.
Select 3-DES if you require network security.
Authentication Select the preferred authentication method. Select one of the following:
• None - indicates that no authentication method is required.
• HMAC-MAC5 - the message authentication code is calculated using
the MD5 cryptographic hash function. This cryptographic hash function
has some additional security properties with a 128-bit hash value,
which is commonly used to check the integrity of files.
• HMAC-SHA1 - the message authentication code is calculated using
the SHA1 algorithm. This cryptographic hash function computes a
condensed digital representation to a high degree of probability.
Preferred Forward Secrecy Select the Preferred Forward Secrecy (PFS). Select one of the following
options:
• None - IKE does not use any PFS.
• PFS Group 1 - IKE uses a 768-bit Diffie-Hellman Prime modules group
for performing the new Diffie-Hellman exchange.
• PFS Group 2 - IKE uses a 1024-bit Diffie-Hellman Prime modules
group for performing the new Diffie-Hellman exchange.
• PFS Group 5 - IKE uses a 1536-bit Diffie-Hellman Prime modules
group for performing the new Diffie-Hellman exchange.
Life Time Select the life time unit. Select one of seconds, minutes, or hours.
Life Time Value Type the life time value.
The range is 5 minutes to 8 hours.
Variable Value