Configuring SNTP

DGS-3100 Series Gigabit Stackable Managed Switch User Manual

To delete a log entry:

1.Select the entry.

2.ClickStratum. The entry is deleted, and the device is updated.

Configuring SNTP

The device supports the Simple Network Time Protocol (SNTP). SNTP assures accurate network device clock time synchronization up to the millisecond. Time synchronization is performed by a network SNTP server. The device operates only as an SNTP client, and cannot provide time services to other systems. The device polls Unicast type servers for the server time.

Time sources are established by stratums. Stratums define the accuracy of the reference clock. The higher stratum (where zero is the highest), the more accurate the clock. The device receives time from stratum 1 and above.

The following is an example of stratums:

Stratum

Stratum 0

Stratum 1

Stratum 2

Example

A real time clock (such as a GPS system) is used as the time source.

A server that is directly linked to a Stratum 0 time source is used as the time source. Stratum 1 time servers provide primary network time standards

The time source is distanced from the Stratum 1 server over a network path. For example, a Stratum 2 server receives the time over a network link, via NTP, from a Stratum 1 server.

Information received from SNTP servers is evaluated based on the Time level and server type. SNTP time definitions are assessed and determined by the following time levels:

Time level

T1

T2

T3

T4

SNTP Time Definition

The time at which the original request was sent by the client.

The time at which the original request was received by the server.

The time at which the server sent the client a reply.

The time at which the client recived the server's reply.

Polling for Time Information

SNTP is used to poll time information from SNTP server. Using SNTP enables accurate system clock.

The Time Settings Page allows network managers to enable and configure the SNTP time settings on the device. To enable SNTP:

1.Click Configuration > SNTP Settings > Time Settings. The Time Settings Page opens:

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D-Link DGS-3100 Configuring SNTP, Stratum Stratum Stratum Stratum, Example, Time level T1 T2 T3 T4, SNTP Time Definition