Content protection: erasure coding

If an ILM rule includes instructions to make erasure coded copies of object data, the applicable erasure coding scheme breaks object data into data and parity fragments and distributes these fragments across the Storage Nodes configured in the Erasure Coding profile.

Data flow

The ILM engine, which is a component of the LDR service, controls erasure coding and ensures that the Erasure Coding profile is applied to object data.


diagram showing process described in surrounding text

  1. The ILM engine queries the ADC service to determine which DDS service can best perform the erasure coding operation. Once determined, the ILM engine sends an "initiate" request to that service.
  2. The DDS service instructs an LDR to erasure code the object data.
  3. The source LDR service sends a copy to the LDR service selected for erasure coding.
  4. Once broken into the appropriate number of parity and data fragments, the LDR service distributes these fragments across the Storage Nodes (LDR services) that make up the Erasure Coding profile’s storage pool.
  5. The LDR service notifies the ILM engine, confirming that object data is successfully distributed.
  6. The ILM engine updates the metadata store with object location metadata.