Spectracom SecureSync User Reference Manual page 120

3.4 Network Time Protocol (NTP)
NTP Servers are close to the physical time references. All Stratum 1 servers can be Trusted
Hosts. One of them is used to generate the IFF Group/Client Key. This defines the IFF Group.
All other group members generate Group Certificate and RSA public/private keys using MD5
digest. Each group member must share the common IFF Group/Client Key (recommended).
Stratum 2 NTP servers are also members of the Group. All NTP Stratum 1 servers are Trusted
Hosts. The NTP servers closest to the actual time reference (Stratum 1) should be designated trus-
ted. A single Stratum 1 NTP server generates the IFF Group/Client Keys. There is NO group name
feature supported. The Group can use the same passphrase (password) or different passphrases
for each client.
An NTP Server Group member is configured by enabling Autokey and creating certificate and pub-
lic/private key pair while not enabling the Client Only selection. A Client Only NTP server is con-
figured by enabling Autokey and creating certificate and public/private key pair and enabling the
Client Only selection.
Figure 3-1:
104
Passphrases can be identical for all group members and Client NTP Serv-
NOTE –
ers. Or passphrases can be the same for group members and a different passphrase
shared between the Client Only NTP Servers.
IFF Autokey configuration example
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3 SecureSync User Reference Guide Rev. 18