Dispersed Storage Network Data Migration and Re-encoding

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional RAID systems face issues with disk failures leading to data loss, increased maintenance costs, and security concerns due to multiple data copies, especially in the event of natural disasters or hardware failures.

Innovation Solution

A dispersed storage network (DSN) that dynamically migrates and re-encodes data across multiple storage tiers based on performance and security requirements, using error encoding and decoding functions to ensure data integrity and security without the need for redundant copies.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If data is copied to multiple RAID devices for redundancy, then data loss risk is reduced, but security risks increase due to multiple accessible copies

Engineering Contradiction:
Improvedata loss riskVSAvoidunauthorized access risk
Core Design Contradiction:
ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The patent segments data into multiple encoded slices distributed across different storage units. Instead of storing complete redundant copies, the system divides data into fragments (slices) and stores them separately, so that no single storage unit contains the complete data, thereby reducing security risks while maintaining reliability through error correction capabilities.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The system changes the parameter of data representation from complete copies to encoded fragments. By applying error correction encoding, the data is transformed into a form where multiple slices are needed for reconstruction, and the system can tolerate a certain number of failed slices without data loss, thus achieving both reliability and security.

Inventive Principle:
Principle #35Parameter changes

2Quantity of substance

If more disks are added to the RAID array for increased storage capacity, then storage capacity is improved, but the probability of disk failure increases leading to higher maintenance costs

Engineering Contradiction:
Improvestorage capacityVSAvoiddisk failure probability
Core Design Contradiction:
Quantity of substanceVSReliability

Solution Approach 1:

The patent implements beforehand cushioning by incorporating error correction codes that provide a buffer against disk failures. The system is designed to tolerate a predetermined number of failed slices before data loss occurs, cushioning the system against the increased failure probability that comes with adding more disks for expanded capacity.

Inventive Principle:
Principle #11Beforehand cushioning (Prior cushioning)

3Device complexity

If data is stored in a single location for simplicity, then device complexity is reduced, but vulnerability to complete data loss from disasters increases

Engineering Contradiction:
Improvestorage system complexityVSAvoiddata loss risk from disasters
Core Design Contradiction:
Device complexityVSReliability

Solution Approach 1:

The system segments data into multiple slices that are distributed across different storage units located in different physical locations. This segmentation approach provides geographic distribution without requiring complex management overhead, as the encoding scheme automatically handles the distribution and reconstruction across dispersed locations.

Inventive Principle:
Principle #1Segmentation

Data Source

PatentUS11327674B2Storage vault tiering and data migration in a distributed storage network
Publication Date: 2022.05.10 PURE STORAGE INC
  • US11327674B2 patent drawing
  • US11327674B2 patent drawing
  • US11327674B2 patent drawing

AI summary

Methods for use in a dispersed storage network (DS) to determine appropriate resources for storing data. An example method, implemented by one or more devices of a dispersed storage network (DSN), includes obtaining storage characteristics relating to data stored in a first pool of storage units associated with a first storage tier, the data stored as a set of encoded data slices. Based on the storage characteristics, the method determines to move the data to a target storage pool of storage units associated with a second storage tier. The method also determines whether to re-encode the data for storage in the target storage pool of storage units. When not re-encoding the data, the method includes retrieving the set of encoded data slices, translating associated slice names into translated slice names, and facilitating storage of the encoded data slices in the target storage pool utilizing the translated slice names.