All-in-one IPv4 / IPv6 Address Lookup

AS5610 (O2 Czech Republic, a.s.) manages the 91.191.96.0/19 prefix block (approximately 8192 addresses) in the Other category. AS5610 independently controls its routing policy, peering relationships and IP allocation — O2 Czech Republic, a.s. is directly responsible for traffic to and from addresses in the 91.191.96.0/19 block. The IP 91.191.103.4 resides in Czechia Praha (timezone Europe/Prague); its position within this block determines routing behavior and connectivity characteristics.

The reverse DNS record resolves to ip-91.191.103.4.o2inet.sk, which may reflect a different service layer or hosting configuration. The mismatch between PTR and provider name may cause elevated scrutiny from mail servers and WAFs during reverse verification.

Based on local classification and Spamhaus real-time reputation, no blacklist entries detected, no security risk flags detected. The Unknown category indicates this IP is part of normal Other infrastructure and carries low inherent risk. Balance risk-control with normal access patterns: standard rate limiting plus CAPTCHA on sensitive flows.

Recommendation: insufficient data to classify 91.191.103.4 — apply a balanced policy: standard rate limiting, CAPTCHA for sensitive operations, and monitor access logs for anomalies. Reassess as the IP's usage history accumulates in this site's archive.