AudioCodes Mediant 8000 - 30 Time and Date Configuration

Version 6.6 265 October 2014
Installation & Operation Manual 30. Time and Date Configuration
30 Time and Date Configuration
The Media Gateway software requires the precise time and date to be set correctly for
normal operations. For example, the following features will not operate correctly when
an incorrect time and date are set:

Secure Call Control and Management protocols that use X.509 certificates (e.g.
SIPS and HTTPS) – due to expiration time, included in the X.509 certificate; see
'X.509 Public Key Infrastructure' on page
325 for details.

Performance measurements – incorrect timestamp and PM values are generated
(see 'Performance Monitoring' on page
401).

Operational and security logs – incorrect timestamp will be used; see 'Internal
Software Logs' on page
871 for details.
The Mediant 8000 Media Gateway lacks a hardware clock that is precise enough and
can survive a chassis power down/up cycle. Therefore, Network Time Protocol (NTP)
is used to synchronize the time and date of the Media Gateway (and all its
components) with the external NTP servers.
The Media Gateway operates as an NTP client and has the following capabilities:

Version 4 of the NTP protocol (as as per the latest draft, available at 'NTP Server'
'
http://www.ntp.org') is implemented.

Backward-compatible with Version 3 of the NTP protocol (as per RFC 1305).

Up to four external NTP servers are supported.

EMS server may be used as a NTP server and is configured as such by default.
30.1 Time Zone Settings
NTP protocol synchronizes the “absolute” time and date (i.e time and date of the GMT
timezone).
The local time on each machine is determined by applying “time zone offset” to the
“absolute” time and date synchronized via the NTP protocol. For example, a machine
that resides in New York, applies “-4” offset, and a machine that resides in Paris,
applies “+1” offset.
Use of the “time zone offset” enables time and date synchronization between
machines that reside in different geographical locations (and therefore different time
zones). In the above example, the two machines will have a five hours difference in
their local time, while maintaining the precise and synchronized clock values.
The Time Zone of the Mediant 8000 is configured during installation or basic
configuration. For detailed description, see 'Installing Mediant 8000 Software' on page
129 and 'Peforming Basic Configuration of the Mediant 8000 Software' on page 146.