HTTP
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GUI
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ROWSER
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ONFIGURATION
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NTERFACE
4985LAN Large Matrix Display 4985 - V08.00
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hopf
Elektronik GmbH
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Duplicate key ID’s are not allowed. Having now explained the principles of keys, it should be
possible to use a key in practically the same way as a password.
The value of the request key field is used as the password for the ntpdc tool while the value of
the control key field is used as the password for the ntpq tool.
More information is available at
5.3.4.8.4 How does authentication work?
The basic authentication is a digital signature and no data encryption (if there are any
differences between the two). The data packet and the key are used to create a non-reversible
number which is attached to the packet.
The receiver (which has the same key) carries out the same calculation and compares the
results. Authentication has been successful if the results agree.
5.3.4.9 Autokey / Public Key Cryptography
NTPv4 offers a new Autokey scheme based on
public key cryptography
.
As a basic principle,
public key cryptography
is safer than
symmetric key cryptography
as protection is based on a private value which is generated by each host and is never visible.
In order to enable Autokey v2 authentication, the "Autokey Enabled" option must be set to
"enabled" and a password specified (may not be blank).
A new server key and certificate can be generated by pressing the "Generate now" button.
Generate now
This should be carried out regularly as these keys are only valid for one
year.
If the Network Time Client 8029NTC is to form part of an NTP trust group, a group key can be
defined and uploaded with the "Upload now" button.
Detailed information about the NTP Autokey scheme can be found in the NTP documentation
(
Changes in data do not take effect immediately after clicking on the "Apply"
symbol. The NTP service MUST also be restarted (see
Chapter 5.3.4.6
).