# Understanding the Logos Blockchain Whitepaper >Title: Understanding the Logos Blockchain Whitepaper | A High-Level Conceptual Overview/Review of the Logos Blockchain > >Purpose: >This document reflects an approach of whitepaper review that combines a rough-draft whitepaper review containing comments/reflections/concerns with a further simplification of concepts to make everything more digestible to more people outside of the internal Status infra team for communication purposes. In addition, this review will provide a gauge of difficulty of understanding involved with various different terms/concepts. > Tags: #learning #whitepaper #Logos --- **"We build everything on top of consensus." ** Dr. Corey Petty --- ## **How-To (Get Cookin')** *Instructions: There are some descriptions below which detail the usage of visual guidance metrics available in the form of "cookbook-like" instructions for how to consume this document:* | Gauges | Description | Visualization | | -------- | :-----------: | :----------: | |Difficulty| 1-10 (Ticks/Pips) | [||||||||||] | |Time | In Minutes | X Minutes | |Resources | Article/Video Links w/ Visual Content | Conceptual & Pictoral "Ingredients List" of Links| See below 'Recipe' and modify accordingly to above in Figma. ![[Pasted image 20220415164934.png]] --- ## **Operating Definitions:** Prep (*Difficulty*) is defined as the ease of which the concepts can be generally understood. (Future: Make into more fun visual or something more enjoyable than a difficulty bar.) Cook Time (*Scope*) is in reference to the size of information necessary to learn to gain a decent level of comprehension. Ingredients (*Resources*) is for links relevant to helping people understand the concepts. Number references and use superscript notation to reference mentions in terminology Recipes descriptions. Future Work: Adjust difficulty/time ratings, cook time respec. based on feedback from everyone at DXB. --- ## Necessary Terminology by Layer --- ### The Six (6) Technology Layers of Logos as a Blockchain tl;dr one to two sentences that group these phrases together - Terminology Template (Recipe): [[here]] - Prep: [||||||||||] - Cook Time: X min - Ingredients: [pictures, videos, article links, research papers, etc.] #### Consensus - [[BBA]] - Prep: [|| ] - Cook Time: X min - Ingredients: 1. https://arxiv.org/pdf/2001.07867.pdf - [[Leaderless ]] - Prep: [||||| ] - Cook Time: X min - Ingredients: 1. https://ieeexplore.ieee.org/document/9546485 - [[DAGs]] - Prep: [| ] - Cook Time: X min - Ingredients: 1. https://en.wikipedia.org/wiki/Directed_acyclic_graph 2. https://tokens-economy.gitbook.io/consensus/chain-based-dag/direct-acyclic-graph-tangle-dag - [[CIC]] - Prep: [| ] - Cook Time: X min - Ingredients: 1. See 'Consensus' section within Logos Specifications - [[P2P Messaging]] - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. https://en.wikipedia.org/wiki/Peer-to-peer - [[Message Passing]] (is a general framework, P2P Messaging is a subset of Message Passing) - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. - [[Gossip Protocol]] (is a subset of P2P Messaging) - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. https://en.wikipedia.org/wiki/Gossip_protocol#:~:text=A%20gossip%20protocol%20or%20epidemic,all%20members%20of%20a%20group. - [[Permissionless]] - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. https://eprint.iacr.org/2021/023.pdf - [[Scalability]] - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. https://eprint.iacr.org/2021/023.pdf 2. https://medium.com/vechain-foundation/what-does-scalability-really-mean-in-blockchain-b8b13b3181c6 3. https://101blockchains.com/blockchain-scalability-challenges/ - [[Decentralization]] - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. https://en.wikipedia.org/wiki/Decentralization 2. https://blockworks.co/measuring-decentralization-is-your-crypto-decentralized/ 3. https://jods.mitpress.mit.edu/pub/7vxemtm3/release/2 - [[Security]] - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. https://arxiv.org/pdf/1802.06993.pdf - [[Communication Costs]] (wrt message complexity - see how this extends into hardware) - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. https://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.221.883&rep=rep1&type=pdf#:~:text=message%20complexity%20denotes%20the%20maximum,last%20node%20completes%20the%20algorithm. - [[Stream or Subgraph]] - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. https://thegraph.com/docs/en/developer/define-subgraph-hosted/ 2. https://streamingfastio.medium.com/streamingfacts-understanding-the-costs-of-upgrading-a-subgraph-fedf5d61223 (is this related?) - [[Staking]] - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. https://deliverypdf.ssrn.com/delivery.php?ID=112001112005005071028123005115028071053009053038065056030075021066021091100007083094098007039126015013042085120028028079118118027039038017006093067005067006124005093039032030000094104124024001105026027114005123097090090111113068087076002030115100122071&EXT=pdf&INDEX=TRUE 2. https://papers.ssrn.com/sol3/papers.cfm?abstract_id=3609817 3. https://papers.ssrn.com/sol3/papers.cfm?abstract_id=4059460 - [[Sybil Resistance]] - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. https://en.wikipedia.org/wiki/Sybil_attack - [[CFT (Crash Fault Tolerant)]] - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. https://medium.com/@chamirachid/your-journey-to-consensus-part-1-6a88a6f818f65 2. https://en.wikipedia.org/wiki/Fault_tolerance5 3. https://dl.acm.org/doi/pdf/10.1145/102792.102801 - [[BFT (Byzantine Fault Tolerant)]] - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. https://en.wikipedia.org/wiki/Byzantine_fault - [[PBFT (Practical Byzantine Fault Tolerant)]] - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. https://www.geeksforgeeks.org/practical-byzantine-fault-tolerancepbft/#:~:text=Practical%20Byzantine%20Fault%20Tolerance%20is,optimized%20for%20low%20overhead%20time. 2. https://www.usenix.org/legacy/events/nsdi09/tech/full_papers/clement/clement.pdf - [[Finality]] - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. https://medium.com/mechanism-labs/finality-in-blockchain-consensus-d1f83c120a9a5 - [[Social Applications]] (look up context) - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. - [[Bootstrapping]] - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. https://en.wikipedia.org/wiki/Bootstrapping_node#:~:text=A%20bootstrapping%20node%2C%20also%20known,successfully%20join%20the%20overlay%20network. - [[Rounds]] - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. - [[Round-less]] - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. - [[Paxos]] - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. - [[DAG-Based Consensus]] - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. https://www.sciencedirect.com/science/article/pii/S2352864819301476 - [[Liveness]] - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. - [[Asynchronous (P2P)]] - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. - [[Execution-Layer Decoupling]] - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. - [[Interchangeability]] - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. - [[Liveness]] - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. - [[Extensibility]] - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. - [[Highly-Partitioned Blockchains with Local Views]] - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. - [[Ordering]] - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. - [[Reputation]] - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. - [[Confidence]] - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. - [[Network Congestion]] - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. - [[Topology]] - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. - [[Resilience (Consensus context)]] - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. - [[Verifiability]] - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. - [[Non-Repudiation]] - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. - [[Snowball]] - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. - [[Lachesis]] - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. - [[Glacier]] - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. #### Node Reputation - [[Ikingut (Reputation Algorithm)]] - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. - [[Important Conceptual Goals]] - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. - Simple - Lightweight - Pluggable - Adaptive - Dynamic - Robust - No Transitive Trust - Reasonable Bootstrap Time - [[Reputation Polling]] (Polling Dynamics) - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. - [[Indirect Request]] - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. - [[Direct Request]] - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. - [[Unirep]] (a pre-existing example) - [[Qualities Necessary]] (of Direct Request) - [[Verifiability]] - [[Non-Repudiation]] - [[Privacy Preserving]] (preserve origins of score, emit opinions without a way to trace back the origins - MPC) - [[ Local Heuristic]] - [[Glacier Algorithm]] - Prep: [||||||||||] - Cook Time: X min - Ingredients: - Each Iteration 1. Voting 2. Agent Action (Post-Consensus Decision Finality) - Min-Multiplicative Reputation Punishment - Multiplicative - Linear - Experimental Research - Starting Point - [[Trust Wisdom per Node]] (requires further elaboration) - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. - [[Adversary Types and Effects]] (requires further elaboration) - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. - Current Stage of Testing/Challenges - [[Silent-Omniscient Adversaries]] - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. - [[Punishment Testing]] (Modulating Punishment/No Punishment Impacts to Conditions) - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. - [[Adding Multiplicative-min Punishment]] - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. - [[Reputation Attacks]] - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. - [[Con-Artist Attack]] - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. - [[The On-Off Attack]] - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. - [[Punishment Effects on Glacier]] - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. - [[Reputation Limitations]] - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. - No immediate defense against coordinated attacks - Reputation does not add to security - Future Work - [[Circumstantial Impact of Reputation on Consensus]] - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. - [[Long-running Simulation]] - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. - [[Sudden changes in Collective Byzantine Behavior]] - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. - Pending Questions 1. Interaction of [[Stake-based]] and [[Reputation-based]] selection - Stake simulations are necessary for exploring options - Relevant in the incentives discussion? 2. How much (and if) does reputation really help in a coordinated attack? (Assuming patient con-artist attack) - Complex interactions here, this model would particularly benefit having a prototype/PoC - [[Node Challenges]] - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. 1. [[Intermittence Flexibility | Maintain Operation in High-Churn Network]] 2. [[Sudden Changing Behavior]] 3. [[Bootstrapping Quickly]] 4. [[Resilience to Dynamic Unpredictable Network Changes (Can Handle Membership Volatility)]] - [[Design]] - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. 1. [[Local reputation view]] 2. [[Adaptive and Dynamic]] 3. [[Required Bootstrapping]] - [[Network View Not Required]] - [[Individual Node Reputation Not Required]] - [[Eigentrust]] - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. - [[Transitive Trust]] - [[Understanding the Math]] - [[Trust Decay]] - [[Malicious Clusters]] (describe nuances better, trusted nodes cannot overlap the malicious collective) - [[Trust for Consensus]] - [[Separation of Reputation]] - [[Confidant]] - [[XRep]] - [[P-Grid]] - [[R2Trust]] - [[Generic Taxonomy]] - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. - [[Dimensions]] - Single - Multiple - [[Time computation]] - [[Aggregation]] - Deterministic sum of positive and negative ratings - Probabilistic - [[Logic]] - Local vs gathered data - Age of data - Frequency of data - Weight of multiple dimensions - [[Value Control]] - External - Internal - [[Data Aging]] - None - Decay - Death of old/selected - [[Selection]] - Ranking-based - Threshold (trusted/untrusted) - Probabilistic selection #### Network Layer and Mempool - [[Node Discovery]] - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. - [[Subnetworks]] - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. - Design - Implementation - Ideas - [[Mempool]] - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. - Challenges - Approach - Mempool Design #### Staking and Multi-DAG - [[Factory of DAGs]] - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. - Concept - Algorithm - [[Sub-DAG]] - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. - [[Cross-DAG]] - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. - [[Bridge (Intermediary) Nodes]] - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. - [[Gravity]] - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. - [[Application-Level User-Driven]] - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. - [[Direct Communication Channel]] - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. - [[Direct Communication VGER]] - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. - Challenges - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. - [[Probabilistic Finality]] and [[Cross-Network Communication]] - [[Network Partitioning]] and [[Forks]] - [[Weak Subjectivity]] - Reputation of nodes matters to clients. Nodes are clients of other networks. - [[Verifying Weights in Staking]] - [[Glacier Algorithm Quiesces]] - [[Approach]] - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. 1. [[Deterministic Finality]] 2. [[Secondary Consensus Protocol]] (form local opinion on external DAG) 3. [[Intermediary DAG]] (Intersection of nodes participating mutually in common structures) - [[Vertex Sealing]] - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. - [[XSub]] (Cross-sub-DAG communication) - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. - [[XDAG]] (Cross-DAG communication) - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. - [[XDAG Fees]] - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. - [[Communication Patterns]] - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. - Direct - User-Coordinated Channel - Sub-DAG-Coordinated Channel - [[Stake Sub-DAG]] - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. - [[Totally-Ordered Chain]] - [[Global Knowledge]] - [[Alternative Designs]] - [[2P-Set]] - [[Per-Node Branch]] #### Data Model and Concurrency - Reference Work - [[eUTXO]] (Direct extension of the basic UTXO model) - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. - References (Cardano foundational paper) - [[Validator]] - [[Datum]] - [[Redeemer]] - [[Ledger Description]] - [[CKB]] - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. - Key feature: [[state space ownership]] - [[Cell description]] - [[Transaction description]] - [[Zexe]] - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. - Key Feature: Privacy - Transaction Description - Record Description - Approach - [[Data Model Design]] - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. - Challenges - Concept - Data Structures and Constraints - [[Concurrent Execution (Threads)]] - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. - [[Execution Patterns]] - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. - Useful patterns - Example of [[EVM execution]] on this model - Explore and describe - [[Anti-patterns]] - High Contention - Low Affinity #### Tokenomics - [[Fees]] - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. - [[Rewards]] - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. - [[Slashing]] - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. - [[MEV]] - Prep: [||||||||||] - Cook Time: X min - Ingredients: 1. ## Relevant Projects ### [[Codex]] ### [[Waku]] ### [[VAC]]