Rename 'landmark checkpoints' to 'landmarks' - #126
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"Landmarks" serve a different role than "checkpoints", so rename to reflect that. In tlog-tiles/static-ct-api, "checkpoints" are signed tree heads/root hashes to summarize the state of the tree. "Landmarks", on the other hand, represent tree sizes (not even tree heads) and trust anchor IDs and are used for coordination amongst parties in the ecosystem. (As a bonus, "landmark sequence" is less of a mouthful than "landmark checkpoint sequence"). Clarify that landmarks don't necessarily need to be aligned with checkpoint tree sizes, and technically could be allocated at any tree sizes less or equal to the latest checkpoint tree size (although not sure why you'd do this). Also clarify that unexpired entries don't necessarily need to be covered by a landmark subtree, as they can be between the last landmark subtree and the log's latest checkpoint.
davidben
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Aug 21, 2025
davidben
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Aug 21, 2025
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"Landmarks" serve a different role than "checkpoints", so rename to reflect that. In tlog-tiles/static-ct-api, "checkpoints" are signed tree heads/root hashes to summarize the state of the tree. "Landmarks", on the other hand, represent tree sizes (not even tree heads) and trust anchor IDs and are used for coordination amongst parties in the ecosystem. (As a bonus, "landmark sequence" is less of a mouthful than "landmark checkpoint sequence").
Clarify that landmarks don't necessarily need to be aligned with checkpoint tree sizes, and technically could be allocated at any tree sizes less or equal to the latest checkpoint tree size (although not sure why you'd do this).
Also clarify that unexpired entries don't necessarily need to be covered by a landmark subtree, as they can be between the last landmark subtree and the log's latest checkpoint.