Stateless VM Certificate Roaming via Directory Service

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Stateless virtual machines cannot store certificates and associated keys due to the lack of persistent memory, leading to network delays during boot processes and difficulties in detecting unauthorized certificate requests, as they require new keys upon every reboot.

Innovation Solution

Implementing a credential roaming mechanism that allows stateless devices to log onto a domain using a managed service account, enabling certificates and private keys to be saved within a directory service like Active Directory, which can be retrieved during subsequent sessions, and configuring autoenrollment mechanisms to reuse existing certificates and keys.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If stateless virtual machines are used to improve security and reduce downtime, then network security and maintenance ease are improved, but the ability to store certificates and private keys is lost

Engineering Contradiction:
Improvenetwork securityVSAvoidcertificate storage capability
Core Design Contradiction:
ReliabilityVSQuantity of substance

Solution Approach 1:

The patent moves certificate storage from the virtual machine dimension (local persistent storage) to the infrastructure dimension (host machine or cloud service storage). This dimensional shift allows stateless VMs to access certificates through the directory service without requiring local storage, resolving the contradiction between stateless operation and certificate persistence.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

Solution Approach 2:

The patent introduces a directory service (Active Directory) as an intermediary between the stateless virtual machine and the certificate storage. The directory service acts as a mediator that stores certificates and private keys, allowing VMs to access them during boot without requiring local storage capability, thus resolving the storage capability loss.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Reliability

If new certificates and private keys are requested during each boot process, then security is maintained through fresh credentials, but network delays increase

Engineering Contradiction:
ImprovesecurityVSAvoidboot time
Core Design Contradiction:
ReliabilityVSLoss of time

Solution Approach 1:

The patent implements preliminary action by having virtual machines obtain and cache certificates and private keys during the first boot or during maintenance windows before they are needed. The credentials are pre-configured in the directory service, allowing subsequent boots to retrieve them quickly without time-consuming generation and issuance processes, thus reducing boot time while maintaining security through controlled credential rotation.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The patent introduces dynamic credential management where the system adapts between two modes: initial credential acquisition (when no cached credentials exist) and rapid credential retrieval (when credentials are cached). This dynamic approach allows the system to optimize for speed during normal operations while ensuring security through periodic credential updates and rotation, resolving the time-security contradiction.

Inventive Principle:
Principle #15Dynamics

3Productivity

If stateless virtual machines reboot frequently, then resource utilization is improved, but detecting unauthorized certificate requests becomes more difficult

Engineering Contradiction:
Improveresource utilizationVSAvoidunauthorized certificate request detection
Core Design Contradiction:
ProductivityVSDifficulty of detecting and measuring

Solution Approach 1:

The patent implements feedback mechanisms through the directory service that logs and monitors all certificate requests, issuances, and revocations. Each virtual machine's certificate activities are tracked and recorded, creating an audit trail that enables detection of unauthorized requests. The system provides feedback to administrators about certificate usage patterns, allowing them to identify anomalies even during frequent reboots, thus resolving the detection difficulty while maintaining high resource utilization.

Inventive Principle:
Principle #23Feedback

Data Source

PatentEP3289750B1Autonomous private key recovery
Publication Date: 2019.07.10 CITRIX SYSTEMS INC
  • EP3289750B1 patent drawingFigure 1
  • EP3289750B1 patent drawingFigure 2
  • EP3289750B1 patent drawingFigure 3

AI summary

Approaches described herein allow a stateless device to recover at least one private key. In particular, a stateless device can provide service-account credentials to a directory service to establish a first session and acquire a certificate and private key using information associated with the stateless device. The stateless device can store its private key before the first session ends. A stateless device can then provide user-account credentials to the directory service to establish a second session. After the second session begins, a private key can be acquired by the stateless device.