Freecom Data Tank Gateway WLAN, Руководство пользователя

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GB
5
Data Tank Gateway in everyday use
MD5
MD5 sums are used by PGP and other programs to check the integrity of files. This involves
comparing the file's current MD5 sum with an accepted sum from earlier. This allows the
system to determine whether the file has been changed or is corrupt.
SHA1
Secure Hash Algorithm (SHA) is the term used to describe a group of standardized cryp-
tographic hash functions.
Working together with the National Security Agency, the National Institute of Standards
and Technology (NIST) developed a secure hash function for signing as part of the Digital
Signature Algorithms (DSA) for the Digital Signature Standard (DSS). It was released in
1994. The name given to it was the Secure Hash Standard (SHS). It specifies the Secure
Hash Algorithm (SHA), with a hash value of 160 bits for messages up to 264 bits in size.
The algorithm shares a similar structure with MD4, designed by Ronald L. Rivest. There
are two versions of the Secure Hash Algorithm: SHA0 and SHA1. They differ in the number
of cycles passed through when generating the hash value.
Pre-Shared Key
Similar to a password. Has to be the same on both VPN routers (Data Tank Gateway and
remote VPN router).
Operation
1. Establish connection - Allows you to establish a connection with another VPN router.
2. Listen Only - Allows you to accept a connection from another router.
Alive Ping IP
You can enter the router's IP address used in establishing a connection in this field. This
involves sending a ping at set intervals to ensure that connection is not cut when no
activity is registered over a long period of time.