UDP 4321
Synopsis
- Remote Who Is (RWhois) directory service — IANA assigns UDP/4321 to RWhois; real deployments include the rwhoisd server historically run by ISPs and registrars referenced by ARIN for network reassignment data.
- Examples: the rwhoisd daemon packages used by providers such as Level 3/CenturyLink and various hosting ISPs exposed RWhois on 4321, with some installations enabling the UDP service in addition to TCP.
- In practice, most RWhois deployments favored TCP 4321, so UDP 4321 usage exists but is relatively uncommon.
Observed activity
Last 30 days
Detailed chart