Hash subtrees for grouping components by component type

A computing system comprising:

• one or more computer-readable storage mediums storing executable instructions for controlling the computing system to generate a hash tree of nodes having hashes, a non-leaf node having a hash of the hashes of its child nodes and a leaf node having a hash of a component of the hash tree, each component from among components having a component type, wherein the components correspond to a transaction, the generating comprising:
• for each component type from among component types of the components, generating a component subtree for the component type based on the hashes of the components of the component type wherein the component subtree for the component type has leaf nodes that only have the hashes of components of the component type and has ancestor nodes of those leaf nodes;
• and
• generating a root subtree of the hash tree with root nodes of the generated component subtrees being leaf nodes of the root subtree by adding to the hash tree ancestor nodes of the root nodes of the component subtrees;
• and
• one or more processors for executing the instructions stored in the one or more computer-readable storage mediums.

One or more computer-readable storage mediums storing executable instructions for generating a portion of a hash tree of nodes having hashes, a non-leaf node having a hash of the hashes of its child nodes and a leaf node having a hash of a component of the hash tree, each component from among components having a component type, wherein the components correspond to a transaction, the hash tree including a component subtree for each component type from among component types of the components, the portion comprising:

• each component that is to be visible;
• a root node of the hash tree;
• and
• for each component type,
• a root node of the component subtree of the component type, that includes, for each component of the component type, a leaf node having a hash of the component and includes ancestor nodes of the leaf nodes, each ancestor node having a hash derived from its child nodes;
• and
• a root node of each highest-level subtree of the component subtree of the component type for which each component of the component subtree is not visible.

A method performed by a computing system for verifying that all components from among components, of a component type of a hash tree of nodes are visible in a portion extracted from the hash tree, wherein the components correspond to a transaction, the hash tree having components grouped by component type from among component types of the components, the hash tree having a component root node of a component subtree for the component type, the method comprising:

• for each component of the component type that is included in the portion, generating a hash of the component;
• and
• generating a leaf node that indicates the hash of that component;
• generating a component hash tree from the generated leaf nodes that includes ancestor nodes of the leaf nodes, each ancestor node indicating a hash of its child components;
• and
• when a root hash of the generated component hash tree matches a generated component root hash of the component subtree of the portion, indicating that all of the components of the component type are visible in the portion.