All-in-one IPv4 / IPv6 Address Lookup

AS4766 (Korea Telecom) manages the 39.16.0.0/12 prefix block (approximately 1048576 addresses) in the ISP Network category. AS4766 independently controls its routing policy, peering relationships and IP allocation — Korea Telecom is directly responsible for traffic to and from addresses in the 39.16.0.0/12 block. The IP 39.23.73.239 resides in South Korea Incheon (timezone Asia/Seoul); its position within this block determines routing behavior and connectivity characteristics.

No reverse DNS (PTR) record is configured, which is common for dynamically assigned or CGNAT'd addresses but limits reverse verification capability. Home-broadband and CGNAT addresses commonly lack PTR records; this limits reverse verification but is normal for dynamic residential pools.

As a Home broadband address, it is part of the ISP's dynamic pool — multiple users may share the same external IP over time, and geolocation accuracy is limited to the ISP's registered region rather than the individual subscriber's location. Residential IPs carry high fraud-prevention value but low geolocation precision; prioritize behavioral signals over address reputation.

Recommendation: 39.23.73.239 is a residential IP — prioritize behavioral signals over IP reputation. Monitor for abnormal request velocity, repeated failed logins or automated patterns. Avoid blanket blocking of residential IPs even when Spamhaus lists them (PBL entries are informational, not indicative of abuse).

If you operate a website or service that receives traffic from this IP, note that the same external address may represent multiple different subscribers behind CGNAT. Blocking this IP could unintentionally exclude legitimate users — consider applying rate-limiting per session rather than per-IP.