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docs/configuration/ntp/index.md

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+# NTP
+
+Built-in NTP client service.
+
+If enabled, it will provide time for protocols like TLS/Shadowsocks/VMess, which is useful for environments where time
+synchronization is not possible.
+
+### Structure
+
+```json
+{
+  "ntp": {
+    "enabled": false,
+    "server": "ntp.apple.com",
+    "server_port": 123,
+    "interval": "30m",
+    
+    ... // Dial Fields
+  }
+}
+
+```
+
+### Fields
+
+#### enabled
+
+Enable NTP service.
+
+#### server
+
+==Required==
+
+NTP server address.
+
+#### server_port
+
+NTP server port.
+
+123 is used by default.
+
+#### interval
+
+Time synchronization interval.
+
+30 minutes is used by default.
+
+### Dial Fields
+
+See [Dial Fields](/configuration/shared/dial) for details.