Network Time Protocol (Ntp); The Ntp Setup Screen - Spectracom SecureSync User Reference Manual

3.4

Network Time Protocol (NTP)

Network Time Protocol (NTP) and Simple Network Time Protocol (SNTP) are client-server pro-
tocols for synchronizing time on IP networks. NTP provides greater accuracy and error checking
than does SNTP.
NTP and SNTP are used to synchronize time on any computer equipment compatible with the Net-
work Time Protocol. This includes Cisco routers and switches, UNIX machines, and Windows
machines with suitable clients. To synchronize a single workstation, several freeware or share-
ware NTP clients are available on the Internet. The software running on the PC determines
whether NTP or SNTP is used.
When the NTP service is enabled, SecureSync will "listen" for NTP request messages from NTP
clients on the network. When an NTP request packet is received, SecureSync will send an NTP
response time packet to the requesting client. Under typical conditions, SecureSync can service
at least 9,000 NTP requests per second without MD5 authentication enabled, and at a somewhat
lower rate with MD5 authentication enabled.
The user can either enable or completely disable the NTP Service. When NTP is disabled, no NTP
time packets will be sent out to the network. When enabled, per default the NTP Service operates
in
Unicast
cast
well as an
Often, it is not necessary to modify the NTP factory default configuration settings. However, most
of the settings can be changed by the user in order to support specific NTP applications which may
require a non-standard configuration: These features include the ability to use either MD5 authen-
tication or NTP Autokey, to block NTP access to parts of the network and to broadcast NTP data
to the network's broadcast address.
Most of these topics listed below can also be accessed through "The NTP Setup Screen" below,
which is a good starting point for 'how-to' instructions. Additional information on
can be found under "NTP Status Monitoring" on page 249.
3.4.1

The NTP Setup Screen

The NTP Setup screen provides access to all NTP configuration settings.
CHAPTER •
3 SecureSync User Reference Guide Rev. 18
NOTE – By default,
sysContact field of the SNMP Status panel of the SNMP Setup page.
mode, i.e. the NTP Service responds to NTP requests only. Also supported are a
mode in which SecureSync sends an NTP time packet to the network broadcast address, as
Anycast mode (see "NTP over Anycast" on page 105.)
NOTE – In order to configure NTP, you need to access the NTP Setup screen which
requires ADMINISTRATOR rights.
techsupport@spectracomcorp.com
3.4 Network Time Protocol (NTP)
is the address in the
Broad-
system monitoring
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