Best Practices for ISPs and ASNs to Optimise IP Geolocation and Enhance Customer Experience

For Internet Service Providers (ISPs) and Autonomous System Number (ASN) operators worldwide, getting IP geolocation right is crucial for delivering a top-notch online experience. Accurate geolocation drives faster content delivery, sharper fraud detection, and seamless location-based services. Inaccurate or incomplete data, on the other hand, can lead to misrouted traffic, faulty fraud flags, or a subpar user experience. By following these best practices, grounded in industry standards and RFC guidelines, you can optimise your network for advanced IP geolocation services like those from BigDataCloud.

1. Enable ICMP Echo Responses on Public Interfaces (RFC 792)

ICMP (Internet Control Message Protocol) echo requests—aka pings—are the backbone of traceroute diagnostics, a must-have tool for advanced IP geolocation providers. At BigDataCloud, we keep ICMP usage minimal and non-disruptive, and we reckon other providers do the same. RFC 792 sets the standard for ICMP, including echo replies, which help map network paths accurately.

Recommendations:

• Enable ICMP echo responses on public-facing router interfaces, but chuck in rate limiting to fend off DDoS risks.
• Don’t block ICMP outright. Set up firewalls to allow Type 8 (Echo Request) and Type 0 (Echo Reply) while filtering unnecessary types.
• Test responsiveness using tools like ping or traceroute from diverse global vantage points to ensure consistent performance.

Why it matters: Proper ICMP setup ensures geolocation services can accurately trace network paths, boosting location precision and cutting latency for users worldwide.

2. Keep Private IPs Off Public Interfaces

Private IP ranges (e.g., RFC 1918: 10.0.0.0/8, 172.16.0.0/12, 192.168.0.0/16) are meant for internal networks only. Using them on public-facing interfaces creates headaches for geolocation providers, leaving blind spots in network mapping and reducing path transparency.

Recommendations:

• Audit router configurations regularly to ensure only public IPs are exposed externally.
• Implement NAT (Network Address Translation) properly to map internal private IPs to external public ones.

Why it matters: Keeping private IPs off public interfaces ensures clear network visibility, critical for accurate geolocation and smooth user experiences across global networks.

3. Announce All Public-Facing Router Interfaces via BGP

Ensuring all public-facing router interfaces are announced via Border Gateway Protocol (BGP) is essential for accurate IP geolocation and efficient routing. Unannounced IPs make it impossible to attribute router interfaces to an ASN, which adds uncertainty in network mapping and may lead to reduced accuracy in IP geolocation, disrupting content delivery and user experience.

Recommendations:

• Announce all public IP interfaces in your BGP routing tables to ensure global reachability and visibility.
• Verify BGP announcements using tools like BGP looking glasses or route servers to confirm that your public IPs are correctly propagated.
• Maintain consistent ASN usage in announcements to avoid confusion in geolocation databases that rely on BGP data for network mapping.

Why it matters: Proper BGP announcements enhance network discoverability, enabling geolocation providers to accurately map your infrastructure. Without clear ASN attribution, network mapping becomes uncertain, reducing IP geolocation accuracy and impacting routing efficiency and user experience globally.

4. Segment Your Networks for Clear RIR Reporting

If your IP blocks mix residential, data centre, or hosting traffic, geolocation providers might misclassify the entire block as “hosting” based on traffic patterns. This can lead to end users being incorrectly flagged by services like banking or streaming that restrict hosting IPs.

Recommendations:

• Sub-allocate IP blocks in Regional Internet Registry (RIR) databases (e.g., ARIN, RIPE, APNIC, LACNIC, AFRINIC). Create separate inetnum objects for data centres, hosting, and end-user networks.
• Use SWIP or equivalent for ARIN-allocated space or other RIRs to clearly delineate network types.
• Monitor traffic patterns: Isolate blocks with high outbound server-like traffic to avoid spillover effects on end-user IPs.

Why it matters: Clear segmentation in RIR databases helps geolocation services assign accurate location data, ensuring users globally aren’t mistakenly flagged or restricted.

5. Design IP Allocations with Geography in Mind

IP blocks spanning massive regions—like entire countries or continents—can muck up geolocation accuracy. For instance, dynamic IP assignments via CGNAT across a large area make it tough to pinpoint locations. With IPv6’s huge address space, there’s no need for overly broad allocations.

Recommendations:

• Follow RFC 6177 and RFC 5375 for IPv6: Allocate a /32 or /30 block for a regional cluster (e.g., a city or metro area), a /48 or /56 per base station or cluster, and a /64 per device.
• For IPv4, aim for geographically tight subnets. Avoid letting /24 subnets cover vast areas like an entire country.
• Plan for scalability: With IPv6, use the ample address space to assign IPs with precise geographic relevance.

Why it matters: Tight geographic allocations enable pinpoint geolocation, improving content delivery speeds and location-based services for users worldwide.

6. Publish Geofeed Data (RFC 8805 and RFC 9632)

If you’ve sorted the above steps, you’re likely in good nick. But for basic geolocation services or if you can’t fully implement the above, publishing a geofeed is a simple, cache-friendly way to map your IP prefixes to coarse locations (country, region, city, postcode). RFC 8805 and RFC 9632 standardise geofeed formats and discovery.

Recommendations:

• Create a geofeed file per RFC 8805. Example format:
  

  ip_prefix,alpha2code,region,city,postal_code
  203.0.113.0/24,US,US-CA,San Francisco,94105
  2001:db8:120::/48,DE,DE-BY,Munich,80331

  Stick to coarse geography (no street-level data) to protect privacy.
• Publish and link it: Add a geofeed: attribute or remarks: Geofeed https://… in your RIR’s inetnum/inet6num objects. RFC 9632 standardises discovery via WHOIS/RDAP; RIPE and APNIC support geofeed: attributes.
• Follow RIR guidance: Check resources from RIRs like APNIC, RIPE, or ARIN for step-by-step geofeed setup instructions.

Why it matters: Geofeeds provide a fallback for basic geolocation, ensuring consistent location data for users globally, even if network configurations aren’t fully optimised.

Conclusion: Level Up Your Network and User Experience

By implementing these best practices, ISPs and ASNs worldwide can boost IP geolocation accuracy, leading to faster content delivery, better fraud detection, and a smoother user experience. Kick off with a network audit—focusing on BGP announcements, RIR data, and ICMP configurations—for quick wins. Tools like BigDataCloud’s APIs can help you test and validate your IP geolocation data.

For network engineers keen to dig deeper, explore RIR resources or reach out for specific implementation advice. By optimising your network, you’re not just improving geolocation—you’re helping build a faster, more reliable internet for users everywhere.