The disc is signed by building SHA-1 hashes of small parts of the disc, then aggregating these hashes into a hierarchical structure, which is finally signed with a asymmetric crypto. This solution is chosen for efficiency, since asymmetric cryptos are extremely slow. | The disc is signed by building SHA-1 hashes of small parts of the disc, then aggregating these hashes into a hierarchical structure, which is finally signed with a asymmetric crypto. This solution is chosen for efficiency, since asymmetric cryptos are extremely slow. |