Spectracom VelaSync 1225, Руководство пользователя

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Note: Please note that it is not advisable to mark more
than one NTP Peer as Preferred , even though VelaSync will
not prevent you from doing so.
5. Click Submit, or press Enter.
2.10.9 NTP Authentication
Since NTP information is distributed across entire networks, NTP poses a security
risk: Falsified NTP time stamps or other NTP-related information can be exploited by an
attacker. NTP authentication keys are used to authenticate time synchronization, thus
detecting a fake time source before it can do harm.
2.10.9.1 NTP: Symmetric Keys (MD5)
Symmetric Keys are an encryption means that can be used with NTP for authentication
purposes.
VelaSync supports authenticated NTP packets using an MD5 authenticator. This fea-
ture does not encrypt the time packets, but attaches an authenticator, which consists
of a key identifier and an MD5 message digest, to the end of each packet. This can be
used to guarantee that NTP packets came from a valid NTP client or server, and that
they were not tampered with during transmission. The Symmetric Keys tab allows NTP
to be configured to use MD5 authentication.
Configuring NTP Symmetric Keys
To create, edit, or delete Symmetric Keys (MD5 Authentication):
1.
Navigate to MANAGEMENT > NETWORK: NTP Setup .
2.
In the Actions panel, click the Symmetric Keys button:
3.
The NTP Symmetric Keys window will display:
2.10 Configuring NTP
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