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system-design/understanding-distributed-systems/part02/README.md

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 - [System Models](#system-models)
 - [Failure Detection](#failure-detection)
 - [Time](#time)
-  - [Physical Clocks](#physical-clocks)
-  - [Logical Clocks](#logical-clocks)
-  - [Vector Clocks](#vector-clocks)
-  - [Summary](#summary)
 - [Leader Election](#leader-election)
-  - [Raft leader election](#raft-leader-election)
-  - [Practical considerations](#practical-considerations)
 - [Replication](#replication)
-  - [State machine replication](#state-machine-replication)
-  - [Consensus](#consensus)
-  - [Consistency models](#consistency-models)
-  - [Chain Replication](#chain-replication)
 - [Coordination avoidance](#coordination-avoidance)
-  - [Broadcast protocols](#broadcast-protocols)
-  - [Conflict-free replicated data types](#conflict-free-replicated-data-types)
-  - [Dynamo-style data stores](#dynamo-style-data-stores)
-  - [The CALM theorem](#the-calm-theorem)
-  - [Causal consistency](#causal-consistency)
-  - [Practical considerations](#practical-considerations)
 - [Transactions](#transactions)
-  - [ACID](#acid)
-  - [Isolation](#isolation)
-  - [Concurrency control](#concurrency-control)
-  - [Atomicity](#atomicity)
-  - [Two-phase commit](#two-phase-commit)
-  - [NewSQL](#newsql)
 - [Asynchronous transactions](#asynchronous-transactions)
-  - [Outbox Pattern](#outbox-pattern)
-  - [Sagas](#sagas)
-  - [Isolation](#isolation)
 - [Summary](#summary)
 
 So far, focus is on making nodes communicate. Focus now is to make nodes coordinate as if they're a single coherent system.