DNS Load Distribution for VoIP Registration Floods

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

VoIP networks face overwhelming registration floods when a large number of endpoints come online simultaneously after a catastrophic failure, leading to SIP registration request failures and infrastructure overload, with existing solutions being static and ineffective in managing the global synchronization of endpoint re-registration.

Innovation Solution

A custom DNS infrastructure with intelligent load distribution across primary and backup border elements, where DNS queries are routed based on threshold capacities, and DNS TTL parameters are randomized to control the reversion of endpoints to their original border elements, preventing message floods and ensuring efficient network recovery.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a large number of endpoints come online simultaneously after catastrophic failure, then endpoint re-registration is achieved, but network infrastructure becomes overwhelmed and registration requests fail

Engineering Contradiction:

Improveendpoint re-registrationVSAvoidregistration flood

Core Design Contradiction:

ReliabilityVSObject-generated harmful factors

Solution Approach 1:

The system performs preliminary actions by having endpoints establish persistent connections to border elements before failure occurs. The border elements maintain active registration states and connection information in advance, so that upon recovery, endpoints can quickly re-establish service without full re-registration, preventing the simultaneous registration flood that overwhelms infrastructure.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The system implements periodic registration refreshes where endpoints maintain their registration by sending periodic REGISTER requests rather than requiring full re-registration after failure. This distributes the registration load over time periods rather than concentrating it all at once during recovery, preventing infrastructure overload while ensuring endpoint re-registration reliability.

Inventive Principle:

Principle #19Periodic action

2Ease of operation

If endpoints use static backoff algorithms for re-registration, then some registration load distribution is achieved, but the solution is ineffective in managing global synchronization of endpoint re-registration

Engineering Contradiction:

Improveregistration controlVSAvoidregistration flood management

Core Design Contradiction:

Ease of operationVSReliability

Solution Approach 1:

The system implements feedback mechanisms where border elements monitor registration request rates and network load conditions, then dynamically adjust registration timing and routing decisions. The DNS system provides feedback by returning different border element addresses based on current load states, and endpoints adjust their re-registration timing based on received feedback about network conditions, enabling effective global synchronization management that static algorithms cannot achieve.

Inventive Principle:

Principle #23Feedback

Solution Approach 2:

The system transitions from static backoff algorithms to dynamic registration control where border element selection and registration timing are continuously adjusted based on real-time network conditions. The DNS system dynamically resolves endpoint addresses to different border elements based on current load states, and the system adapts registration rates according to network capacity, making the registration control both easier to operate and more reliable under varying conditions.

Inventive Principle:

Principle #15Dynamics

3Ease of operation

If DNS queries are routed to primary border elements without load consideration, then endpoint registration is simplified, but border element capacity is exceeded during high query volumes

Engineering Contradiction:

ImproveDNS query processingVSAvoidborder element throughput

Core Design Contradiction:

Ease of operationVSProductivity

Solution Approach 1:

The system changes the parameter of border element selection by introducing load-based routing into the DNS resolution process. Instead of always routing to the primary border element, the system dynamically changes which border element receives DNS queries based on current capacity parameters, allowing simplified endpoint operation while maintaining border element throughput within acceptable limits through intelligent load distribution.

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The DNS system acts as an intermediary between endpoints and border elements, mediating the registration process by intelligently routing DNS queries to appropriate border elements based on their current capacity. This intermediary function simplifies endpoint operation (endpoints just query DNS) while preventing border element overload through smart load distribution, resolving the contradiction between operational simplicity and throughput capacity.

Inventive Principle:

Principle #24Intermediary (Mediator)

Data Source

PatentUS10063599B2Controlling registration floods in VOIP networks via DNS

Publication Date: 2018.08.28 AT&T INTELLECTUAL PROPERTY I L P

AI summary

A mechanism controls global synchronization, or registration floods, that may result when a large number of endpoints in a Voice over Internet Protocol (VoIP) network such as an Internet Protocol Multimedia Subsystem (IMS) come online simultaneously after a catastrophic failure. The mechanism allows the Domain Name System (DNS) infrastructure to efficiently control the overload condition by registering user end points with backup border elements, and by staggering and by randomizing the time-to-live (TTL) parameter in registrations with backup border elements.