IPS - NTP v4 tab

Basic configuration

Maximum size of packets (bytes)

Enter the maximum size allowed for NTP v4 packets (default value: 72 bytes).

NTP modes

This list sets out the known NTP v4 modes (reserved, active symmetric, passive symmetric, client, server, broadcast, NTP control messages and private use) and the action applied to each one of them.

The action (Analyze / Block) applied to each mode can be changed by double-clicking in the corresponding action column.

Advanced properties

Reference ID management

This table allows blacklisting or whitelisting additional NTP Reference IDs (LOCL, LCL, etc.).

Click on Block All to move all predefined NTP Reference IDs from the whitelist to the blacklist.

Reference IDs can also be added or deleted:

• Click on Add and specify the name of the Reference ID,
• Select a Reference ID and click on Delete.

Kiss of death packets

This table allows blacklisting or whitelisting additional Reference IDs that may be involved in Kiss of Death attacks (DENY, RSTR, RATELCL, etc.).

Click on Block All to move all predefined NTP Reference IDs from the whitelist to the blacklist.

Reference IDs can also be added or deleted:

• Click on Add and specify the name of the Reference ID,
• Select a Reference ID and click on Delete.