All-in-one IPv4 / IPv6 Address Lookup

AS15557 (Societe Francaise Du Radiotelephone - SFR SA) manages the 78.115.184.0/21 prefix block (approximately 2048 addresses) in the Other category. AS15557 independently controls its routing policy, peering relationships and IP allocation — Societe Francaise Du Radiotelephone - SFR SA is directly responsible for traffic to and from addresses in the 78.115.184.0/21 block. The IP 78.115.187.171 resides in France Provence-Alpes-Côte d'Azur Sainte-Luce-sur-Loire (timezone Europe/Paris); its position within this block determines routing behavior and connectivity characteristics.

The reverse DNS record resolves to 171.187.115.78.rev.sfr.net, which is consistent with the registered provider. This alignment with the registered provider is favorable for email deliverability and system trust scores.

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: 78.115.187.171 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.