Your web browser sends an HTTP request to the server, which is assigned your public IP address (known as the source IP). Without this address, the website content could not be delivered. Our server compares your source IP with the IP address prefixes (address blocks) that are propagated to the internet by the respective providers using BGP (Border Gateway Protocol). Each prefix is thus assigned to an Autonomous System (AS). Each AS has a globally unique ASN, or Autonomous System Number. Swisscom, for example, uses the number 3303, Sunrise 6730, Init7 13030 and Salt 15796. This IP → ASN mapping is publicly available routing information and part of the global routing table.
We map your source IP to the corresponding ASN. Based on this ASN, the server delivers a simple HTTP redirect – you will then see information tailored to your provider. We do not use cookies, third-party tracking or fingerprinting – we only use publicly available and anonymous internet data. Try it out by connecting to another provider's network (e.g. mobile vs. Wi-Fi).