SDN Trust Controller Authorizing FDT Modifications

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Software-Defined Networks (SDNs) face challenges in maintaining hardware trust due to potential mistakes or malicious acts that can corrupt Flow Description Tables (FDTs) in data-plane machines, leading to impacts on user data services, as well as vulnerabilities from viruses and spoofing by criminal elements.

Innovation Solution

A trust controller and trust processor exchange hardware-trust data over an SDN southbound interface to authorize FDT modifications in data-plane machines, using hardware security keys and digital certificates to ensure secure operations, and maintain hardware trust by identifying and isolating unauthorized flow controllers and untrusted data-plane machines.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If FDT modifications are allowed in SDN data-plane machines, then service delivery and efficiency are improved, but security and reliability deteriorate due to potential corruption from mistakes or malicious acts

Engineering Contradiction:
Improveservice delivery efficiencyVSAvoidFDT security
Core Design Contradiction:
ProductivityVSReliability

Solution Approach 1:

A trust controller is introduced as an intermediary component between the flow controller and data-plane machines. The trust controller verifies hardware trust credentials and authorizes FDT modifications, preventing unauthorized changes while allowing legitimate service delivery improvements. This mediator resolves the contradiction by enabling productivity gains through controlled FDT modifications while maintaining reliability through hardware-based authorization.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Reliability

If hardware-trust verification is implemented, then security against spoofing and malicious acts is improved, but device complexity increases due to additional trust controllers and verification protocols

Engineering Contradiction:
Improvehardware trust securityVSAvoidSDN system architecture
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

Data-plane machines are equipped with hardware-based trust credentials that automatically verify their own identity and authorization status. The trust controller leverages these self-verified credentials to make authorization decisions, reducing the need for complex manual verification protocols. This self-service approach maintains high security while minimizing the added system complexity.

Inventive Principle:
Principle #25Self-service

3Reliability

If digital certificates and key exchanges are used for hardware-trust, then authentication reliability is improved, but processing time and operational complexity worsen

Engineering Contradiction:
Improveauthentication trustVSAvoidtrust verification time
Core Design Contradiction:
ReliabilityVSLoss of time

Solution Approach 1:

Hardware trust credentials including digital certificates and cryptographic keys are pre-configured in data-plane machines during manufacturing or initial deployment. This preliminary setup eliminates the need for time-consuming key generation and certificate exchange during operational trust verification. The pre-configured credentials enable rapid authentication while maintaining high security, thus improving processing speed without sacrificing authentication reliability.

Inventive Principle:
Principle #10Preliminary action

Data Source

PatentEP3357207B1Software-defined network threat control
Publication Date: 2019.08.28 SPRINT COMMUNICATIONS CO LP
  • EP3357207B1 patent drawingFigure 1
  • EP3357207B1 patent drawingFigure 2
  • EP3357207B1 patent drawingFigure 3

AI summary

In Software-Defined Network (SDN) (100 and 500) a trust controller (111) and trust processor (121) exchange hardware-trust data over an SDN southbound interface (113) to maintain hardware-trust. A flow controller (112) transfers a Flow Description Table (FDT) modification to the data-plane machine (126) over the southbound interface (114). The flow controller (112) transfers an FDT modification notice to the trust controller (111) which transfers FDT security data over the southbound interface (113) to authorize the FDT change in the SDN data-plane machine (120). The data-plane machine (126) authorizes the FDT modification based on the FDT security data from the trust controller (111). The data-plane machine (126) modifies the FDT in response to the successful authorization and processes user data traffic using the modified FDT. The trust controller (111) may also transfer a Threat Description Table (TDT) to the data-plane machine (126) to filter the user traffic for other threats.