Authoritative DNS Zone Nonexistent Domain Forwarding

Solution Overview

Problem

Authoritative DNS zones often lack awareness of IP addresses for external services, leading to non-existent domain (NXDomain) responses when attempting to resolve domain names, which can result in service unreachability and increased risk of blackouts.

Innovation Solution

Implementing a system where a client device queries an authoritative DNS zone, which, if unable to find the domain name within its records, uses an external forwarder service to retrieve the IP address from an external DNS service.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If authoritative name servers only resolve domains within their authoritative zone without recursive queries, then DNS resolution authority and security are maintained, but external service IP addresses cannot be resolved leading to NXDomain responses

Engineering Contradiction:

ImproveDNS resolution authorityVSAvoidExternal service accessibility

Core Design Contradiction:

ReliabilityVSAdaptability or versatility

Solution Approach 1:

The patent introduces an intermediary component that sits between the authoritative DNS zone and external DNS services. This intermediary receives domain name resolution requests, attempts to resolve them within the authoritative zone, and if unsuccessful, forwards the request to external DNS services. The intermediary then returns the resolved IP address to the client, enabling access to external services while maintaining the authoritative zone's non-recursive resolution policy.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Measurement precision

If authoritative name servers return NXDomain for unknown domain names, then DNS protocol correctness is maintained, but service unreachability and blackouts occur

Engineering Contradiction:

ImproveDNS protocol accuracyVSAvoidService availability

Core Design Contradiction:

Measurement precisionVSReliability

Solution Approach 1:

The patent implements preliminary action by proactively querying external DNS services before returning an NXDomain response. The system first checks if the domain exists in the authoritative zone, and if not found, preemptively queries external DNS services to determine if the domain is accessible elsewhere. Only after confirming the domain is truly unavailable does the system return an NXDomain response, thereby avoiding premature service unreachability while maintaining protocol accuracy.

Inventive Principle:

Principle #10Preliminary action

3Object-affected harmful factors

If DNS resolution is restricted to authoritative zone only, then security and control are improved, but external service accessibility deteriorates

Engineering Contradiction:

ImproveDNS securityVSAvoidExternal service access

Core Design Contradiction:

Object-affected harmful factorsVSEase of operation

Solution Approach 1:

The patent introduces an intermediary component that sits between the authoritative DNS zone and external DNS services. This intermediary receives domain name resolution requests, attempts to resolve them within the authoritative zone, and if unsuccessful, forwards the request to external DNS services. The intermediary then returns the resolved IP address to the client, enabling access to external services while maintaining the authoritative zone's non-recursive resolution policy.

Inventive Principle:

Principle #24Intermediary (Mediator)

Data Source

PatentUS12267294B1Nonexistant domain forwarding in authoritative zones

Publication Date: 2025.04.01 UNITED SERVICES AUTOMOBILE ASSOCIATION (USAA)

AI summary

Systems and techniques are provided herein to enable an authoritative DNS zone to selectively utilize a forwarding service to resolve domain names that cannot be resolved by the authoritative DNS zone. A forwarder indication may be provided in an authoritative DNS zone configuration file specific to the authoritative DNS zone to indicate whether the forwarding service is active.