Table of Links
Abstract and 1. Introduction
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Key Concepts
2.1 Append-Only Log and 2.2 Virtual Machine State
2.3 Transactions As Curried Functions
2.4 Natural Names of State
2.5 Ground Truth
2.6 Efficient Representations of State
2.7 Checkpoints
2.8 Execution Parameters: callData
2.9 Execution Ordering
2.10 Deciding on the Correct State
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Ideal Layer 2 Design
3.1 VM Job Queue and Transaction Order Finality
3.2 Data Availability and Garbage Collection
3.3 State Finality
3.4 Checkpoint Finality
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Conclusion and References
A. Discrepancy Detection Security Parameters
4 Conclusion
The main contribution of this paper is that transaction order finality should be viewed as the key for determining system state. Computing an efficient representation is just an optimization, since state can be reconstituted from a checkpoint state and those transactions that follows it. We identify the following shades of finality: log finality, transaction order finality, state finality, and checkpoint finality. These notions are useful for reasoning about blockchain design and the design space for error/fault handling, from independent faults due to Byzantine actors to common-mode faults due to zero-day software defects.
Based on considering how and when these finality properties should be achieved, we developed a preliminary design sketch for an “ideal” layer 2 system, and discussed some of the trade-offs.
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Authors:
(1) Bennet Yee, Oasis Labs;
(2) Dawn Song, Oasis Labs;
(3) Patrick McCorry, Infura;
(4) Chris Buckland, Infura.
