Prerequisites for Zero Touch Provisioning
|
Service |
Port |
Protocol |
Direction |
Purpose |
|---|---|---|---|---|
|
Public DNS resolver |
53 |
UDP / DNS |
Outbound |
The device must be able to resolve public names. |
|
NTP time source |
123 |
UDP / NTP |
Outbound |
Clock sync. A wrong clock fails certificate validity checks and fails the TLS handshake. |
|
Time Zone Database (tz / zoneinfo) |
443 |
HTTPS |
Outbound |
Time zone data refresh on Android-based devices. |