Zab protocol

E705296

atomic broadcast protocol consensus algorithm crash-recovery protocol

The Zab protocol is a crash-recovery atomic broadcast and consensus algorithm used by Apache ZooKeeper to ensure ordered, reliable updates across distributed nodes.

Try in SPARQL Jump to: Surface forms Disambiguation Statements Elicitation Referenced by

All labels observed (3)

Label	Occurrences
Zab protocol canonical	1
ZooKeeper Atomic Broadcast protocol	1
“Zab: High-performance broadcast for primary-backup systems”	1

How this entity was disambiguated

This entity first appeared as the object of triple T7985810 — resolving that mention is where its identity was fixed. The disambiguator weighed these candidate entities and picked the highlighted one (or “None”, minting a new entity). This is how homonymy is resolved: the same surface form can point to different entities.

NED1 Entity disambiguation (via context triple) gpt-5-mini-2025-08-07

Target entity: Zab protocol
Context triple: [Apache ZooKeeper, consensusAlgorithm, Zab protocol]

A. Paxos
Paxos is a small Greek island in the Ionian Sea, known for its clear turquoise waters, olive groves, and tranquil, less-touristed atmosphere.
B. Paxos consensus algorithm
The Paxos consensus algorithm is a fault-tolerant protocol for achieving agreement among distributed systems, widely used as a foundation for reliable, replicated state machines and modern distributed databases.
C. Raft consensus algorithm
Raft consensus algorithm is a distributed consensus protocol designed to be more understandable and easier to implement than Paxos while providing equivalent fault-tolerant guarantees.
D. Algorand blockchain protocol
Algorand blockchain protocol is a scalable, secure, and energy-efficient public blockchain platform designed by cryptographer Silvio Micali that uses a pure proof-of-stake consensus mechanism.
E. Practical Byzantine Fault Tolerance
Practical Byzantine Fault Tolerance is a consensus algorithm for distributed systems that efficiently tolerates Byzantine (arbitrary) faults, enabling reliable operation even when some nodes behave maliciously or unpredictably.
F. None of above. chosen
G. Unsure - the case is ambiguous/there is not enough information to decide.

NED2 Entity disambiguation (via description) gpt-5-mini-2025-08-07

Target entity: Zab protocol
Target entity description: The Zab protocol is a crash-recovery atomic broadcast and consensus algorithm used by Apache ZooKeeper to ensure ordered, reliable updates across distributed nodes.

A. Paxos
Paxos is a small Greek island in the Ionian Sea, known for its clear turquoise waters, olive groves, and tranquil, less-touristed atmosphere.
B. Paxos consensus algorithm
The Paxos consensus algorithm is a fault-tolerant protocol for achieving agreement among distributed systems, widely used as a foundation for reliable, replicated state machines and modern distributed databases.
C. Raft consensus algorithm
Raft consensus algorithm is a distributed consensus protocol designed to be more understandable and easier to implement than Paxos while providing equivalent fault-tolerant guarantees.
D. Algorand blockchain protocol
Algorand blockchain protocol is a scalable, secure, and energy-efficient public blockchain platform designed by cryptographer Silvio Micali that uses a pure proof-of-stake consensus mechanism.
E. Practical Byzantine Fault Tolerance
Practical Byzantine Fault Tolerance is a consensus algorithm for distributed systems that efficiently tolerates Byzantine (arbitrary) faults, enabling reliable operation even when some nodes behave maliciously or unpredictably.
F. None of above. chosen

Statements (45)

Predicate	Object
instanceOf	atomic broadcast protocol ⓘ consensus algorithm ⓘ crash-recovery protocol ⓘ
assumes	non-Byzantine failures ⓘ reliable communication channels ⓘ
designedFor	distributed systems ⓘ replicated state machines ⓘ
ensures	committed transactions survive leader changes ⓘ followers apply transactions in the same order as leader ⓘ only one active leader at a time ⓘ
ensuresProperty	atomic broadcast ⓘ durable updates ⓘ ordered updates ⓘ reliable broadcast ⓘ total order broadcast ⓘ
fullName	ZooKeeper Atomic Broadcast protocol ⓘ linked to: Zab protocol
guarantees	agreement among non-faulty nodes ⓘ liveness under partial failures ⓘ no data loss for committed transactions ⓘ prefix ordering of committed transactions ⓘ
handles	follower crash recovery ⓘ leader crash recovery ⓘ
hasAbbreviation	Zab ⓘ
hasPhase	broadcast phase ⓘ discovery phase ⓘ leader election phase ⓘ synchronization phase ⓘ
hasProperty	leader-based atomic broadcast ⓘ log-based state replication ⓘ primary-backup style replication ⓘ
implementedIn	Apache ZooKeeper server codebase ⓘ
inspiredBy	Viewstamped Replication ⓘ linked to: Paxos consensus algorithm
maintains	global order of ZooKeeper transactions ⓘ
publication	“Zab: High-performance broadcast for primary-backup systems” ⓘ linked to: Zab protocol
relatedTo	Paxos ⓘ linked to: Paxos consensus algorithm Raft consensus algorithm ⓘ
requires	distinguished leader ⓘ
supportsModel	crash-recovery failure model ⓘ
usedBy	Apache Hadoop ecosystem components via ZooKeeper ⓘ Apache ZooKeeper ⓘ
usedFor	coordination in distributed applications ⓘ leader-based replication ⓘ replicated log management ⓘ
usedIn	ZooKeeper quorum-based write operations ⓘ ZooKeeper transaction ordering ⓘ

How these facts were elicited

Referenced by (3)

Full triples — surface form annotated when it differs from this entity's canonical label.

Apache ZooKeeper → consensusAlgorithm → Zab protocol ⓘ

Zab protocol → publication → “Zab: High-performance broadcast for primary-backup systems” ⓘ

linked to: Zab protocol

Zab protocol → fullName → ZooKeeper Atomic Broadcast protocol ⓘ