GeoIP Headers (Request Metadata)

When smoxy forwards requests to your origin servers, it automatically adds a set of HTTP headers containing geolocation and network metadata derived from the client’s IP address. These GeoIP Headers enable dynamic content personalization, language switching, regional compliance, and advanced analytics — all at the edge, before the request even hits your backend.

Also known as: GeoIP Headers, Edge Headers, IP Geolocation Headers, Location Headers, Geo Headers

Overview

These headers are injected into every request by smoxy’s edge infrastructure. They provide rich client context, including the user’s approximate location, network provider, and EU status. This information is resolved in real-time using fast, privacy-conscious IP lookup services.

Included Headers

Header	Description
s-asn	ASN (Autonomous System Number) of the client’s network
s-asorg	Organization name for the ASN (e.g., “Cloudflare, Inc.”)
s-country	ISO 3166-1 alpha-2 country code (DE, US, etc.)
s-city	Approximate city of the client
s-latitude	Approximate latitude
s-longitude	Approximate longitude
s-subdivisions	ISO 3166-2 region/subdivision codes (e.g., DE-BY)
s-iseu	Flag indicating whether the request originates from within the EU (1 or 0)

These values are useful for building location-aware features or routing logic directly in your backend.

Use Cases

Language Redirection

Automatically redirect users to a localized version of your site:

$country = $_SERVER['HTTP_S_COUNTRY'] ?? 'US';

$language = match ($country) {
    'DE' => 'de',
    'FR' => 'fr',
    default => 'en',
};

header("Location: /{$language}/");
exit;

GDPR Compliance

Use s-iseu to trigger EU-only consent dialogs:

if ($_SERVER['HTTP_S_ISEU'] === '1') {
    // Show GDPR consent UI
}

IP-Based Routing and Blocking

Allow or restrict access based on ASN or country:

$asn = $_SERVER['HTTP_S_ASN'] ?? null;

if ($asn === '12389') {
    http_response_code(403);
    exit('Access denied for this network');
}

Enhanced Logging / Analytics

Store s-country or s-asorg alongside other request metadata to enrich logs and traffic reports.

Integration Notes

• Header names are prefixed with s- to avoid conflicts with standard HTTP headers.

• Values are added at the edge by smoxy, so they’re present even before your app processes the request.

• These headers are available in all environments — no client-side JS required.

Best Practices

• Always treat geolocation as approximate — avoid relying on city-level accuracy for critical decisions.

• Provide fallbacks for cases where headers are missing (e.g., during local dev).

• Consider logging these values for auditing or debugging location-based behavior.