Billion BiGuard 30, Руководство пользователя

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degrees of security and speed of negotiation:
Main Mode: Uses the automated Internet Key Exchange (IKE) setup; most
secure method with the highest level of security.
Aggressive Mode: Uses the automated Internet Key Exchange (IKE) setup;
mid-level security. Speed is faster than Main mode.
Manual Key: Standard level of security. It is the fastest of the three
methods.
Method: There are two methods of checking the authentication information, AH
(Authentication Header) and ESP (Encapsulating Security Payload). Use ESP for
greater security so that data will be encrypted and authenticated. AH data will be
authenticated but not encrypted.
Encryption Protocol: Select the encryption method from the pull-down menu.
There are several options: DES, 3DES, and AES (128, 192 and 256). 3DES and AES
are more powerful but increase latency.
DES: Stands for Data Encryption Standard. It uses a 56-bit encryption
method.
3DES: Stands for Triple Data Encryption Standard. It uses a 168-bit
encryption method.
AES: Stands for Advanced Encryption Standard. You can use 128, 192 or
256 bits as encryption method.
Authentication Protocol: Authentication establishes data integrity and ensures
it is not tampered with while in transit. There are two options: Message Digest 5
(MD5), and Secure Hash Algorithm (SHA1). While slower, SHA1 is more resistant to
brute-force attacks than MD5.
MD5: A one-way hashing algorithm that produces a 128 − bit hash.
SHA1: A one-way hashing algorithm that produces a 160 − bit hash.
Perfect Forward Secure: Choose whether to enable PFS using Diffie-Hellman
public-key cryptography to change encryption keys during the second phase of VPN
negotiation. This function will provide better security, but extends the VPN
negotiation time. Diffie-Hellman is a public-key cryptography protocol that allows
two parties to establish a shared secret over the Internet.
Pre-shared Key: This is for the Internet Key Exchange (IKE) protocol. IKE is
used to establish a shared security policy and authenticated keys for services (such
as IPSec) that require a key. Before any IPSec traffic can be passed, each router
must be able to verify the identity of its peer. This can be done by manually entering
the pre-shared key into both sides (router or hosts).
IKE Life Time: Allows you to specify the timer interval for renegotiation of the
IKE security association. The value is in seconds, eg. 28800 seconds = 8 hours.