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Configure Simple Network Time Protocol (SNTP) Authentication Settings on a Switch


Simple Network Time Protocol (SNTP) is the simplified version of Network Time Protocol (NTP). NTP is the protocol that is used to synchronize the clocks on a network. It provides time within 100 milliseconds of the accurate time, but does not authenticate traffic.

The SNTP authentication page of the switch allows the administrator to configure Network Time Protocol (NTP) authentication keys to verify a time source. SNTP authentication should be used only in situations where strong authentication is not required as it does not provide the complex filtering mechanisms of NTP.

This document explains how to define SNTP Authentication on a switch.

Applicable Devices

  • Sx250 Series
  • Sx300 Series
  • Sx350 Series
  • SG350X Series
  • Sx500 Series
  • Sx550X Series

Software Version

  • — Sx300, Sx500
  • — Sx250, Sx350, SG350X, Sx550X

Configure SNTP Authentication

Step 1. Log in to the web-based utility of the switch.

Step 2. Choose Advanced from the Display Mode drop-down list.

Step 3. Choose Administration > Time Settings > SNTP Authentication.

Step 4. Check the SNTP Authentication Enable check box.

Step 5. Click Apply to update the switch.

Step 6. Click Add.

Step 7. Enter the number used to identify this SNTP authentication key in the Authentication Key ID field.

Note: In this example, 121110 is entered.

Step 8. Choose an Authentication Key. The options are:

  • User Defined (Encrypted) — This option encrypts the Authentication Key.
  • User Defined (Plaintext) — This option displays the Authentication Key in plain text.

Note: In this example, User Defined (Plaintext) is chosen.

Step 9. (Optional) Enter the key used for authentication in the Authentication Key field.

Note: In this example, 12112010 is entered.

Step 10. Check the Trusted Key Enable check box to allow the switch to receive synchronization information only from an SNTP server with the use of this authentication key.

Step 11. Click Apply.

Step 12. (Optional) Click Save.

You should now have successfully configured SNTP Authentication settings on your switch.