Ntp Access Restrictions - Spectracom SecureSync 1200 User Reference Manual

2.15 Configuring NTP
6.
The key(s) you have set up will now appear as options in the Symmetric Key field in
both the NTP Server screen, and the NTP Peer screen.
NOTES:
Duplicate key IDs are not permitted. NTP requests received by that do not contain an authen
ticator containing a valid Key ID and MD5 message digest pair will be responded to, but no
authentication will be performed. An NTP request with valid authenticators results in a valid
NTP response with its own valid authenticator using the same Key ID provided in the NTP
request.
You may define the trusted Symmetric Keys that must be entered on both SecureSync, and any
network client with which SecureSync is to communicate. Only those keys for which the "Trus
ted" box has been checked will appear in the dropdown menus on the NTP References screen.

2.15.10 NTP Access Restrictions

Next to encrypted authentication by means of Symmetric Keys, NTP supports a list-based means
of access restriction, the use of which is also recommended to prevent fraudulent or inadvertent
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