A general private information retrieval scheme for MDS coded databases with colluding servers

Understand

The problem of private information retrieval gets renewed attentions in recent years due to its information-theoretic reformulation and applications in distributed storage systems.

• PIR capacity is the maximal number of bits privately retrieved per one bit of downloaded bit.
• The capacity has been fully solved for some degenerating cases.
• For a general case where the database is both coded and colluded, the exact capacity remains unknown.