Settlement paradigms

A rollup's settlement paradigm decides how a settlement batch becomes final once it is anchored to the Main Chain. The RDK supports four, and enforces a compatibility matrix that ties each paradigm to the sequencer modes and proof systems it can use.

Paradigm	Finality	Proofs	Sequencer	Notes
optimistic	Delayed (challenge window)	Interactive fraud proofs	dedicated / shared	Default 7-day window with a challenge bond
zk	Instant on a valid proof	SNARK or STARK	dedicated / shared	On-chain verification gates finalization
based	~2 blocks	None	based only	Host-chain proposers sequence the rollup
sovereign	The rollup's own consensus	None	dedicated / shared	Self-sequenced, settles off the Main Chain

optimistic

A batch is accepted on submission without a proof and finalizes after a challenge window (default 7 days) unless a challenger proves it fraudulent. Challenges and the operator's response are interactive fraud proofs, backed by a challenge bond. Optimistic settlement uses the fraud proof system.

Choose it when you want low submission overhead and can tolerate delayed finality — general-purpose app-chains, NFT platforms, anything not latency- critical.

zk

Each batch carries a validity proof — a snark or a stark. The proof is verified on-chain, and a valid proof gates finalization, so a verified batch finalizes immediately with no challenge window. The RDK does not implement or describe the verifier; your rollup produces proofs in the encoding the network's on-chain verifier expects.

Choose it when you need fast, trust-minimized finality — high-value DeFi, exchanges, anything that benefits from cryptographic finality without a wait.

based

Ordering and inclusion are inherited from host-chain proposers, giving roughly two-block finality with no separate proof. Based settlement requires the based sequencer mode (the rollup does not run its own sequencer).

Choose it when you want fast finality and tight coupling to the host chain's liveness, and are comfortable delegating sequencing — high-throughput gaming or enterprise rollups.

sovereign

The rollup runs its own consensus and settles off the Main Chain; it anchors data but carries no proofs or challenges. Finality is whatever the rollup's own consensus provides.

Choose it when you want maximum autonomy over consensus and settlement and are using QoreChain primarily for anchoring and data availability.

Compatibility

The paradigm constrains the proof system and (for based) the sequencer mode:

• optimistic → fraud
• zk → snark | stark
• based → none (and based sequencer mode)
• sovereign → none

The RDK validates these before anything is submitted. See Proof systems for the full matrix and Sequencer modes for the based constraint.