Walrus Glossary

To make communication as clear and efficient as possible, we make sure to use a single term for every Walrus entity/concept and do not use any synonyms. The following table lists various concepts, their canonical name, and how they relate to or differ from other terms.

Italicized terms in the description indicate other specific Walrus terms contained in the table.

Approved nameDescription
2D encodingencoding scheme used in RedStuff where each blob is encoded in two dimensions—primary and secondary—to ensure robust recovery and redundancy
aggregatorservice that reconstructs blobs by interacting with storage nodes and exposes a simple HTTP GET endpoint to users
availability periodthe period specified in (Walrus) epochs for which a blob is certified to be available on Walrus
blobsingle unstructured data object stored on Walrus
blob IDcryptographic ID computed from a blob’s slivers
blob metadatametadata of one blob; in particular, this contains a hash per shard to enable the authentication of slivers and recovery symbols
cachean aggregator with additional caching capabilities
certificate of availability (CoA)a blob ID with signatures of storage nodes holding at least shards in a specific epoch
cliententity interacting directly with the storage nodes; this can be an aggregator/cache, a publisher, or an user
committeethe set of storage nodes for a particular epoch, including metadata about the shards they are responsible for and other metadata
deletable blobblob which can be deleted by its owner at any time to be able to reuse the storage resource
end epochthe epoch at which a blob will no longer be available for reads; the end epoch is always exclusive
epochWalrus uses epochs to track committee changes (like Sui) and measure lifetimes of blobs; the epoch duration for Walrus differs from Sui; on Mainnet the epoch duration is two weeks
expirya blob becomes unavailable and can be deleted by storage nodes at its end epoch
FROSTthe smallest unit of WAL (similar to MIST for SUI); 1 WAL is equal to 1 billion (1000000000) FROST
inconsistency certificatean aggregated signature from 2/3 of storage nodes (weighted by their number of shards) that they have seen and stored an inconsistency proof for a blob ID
inconsistency proofset of several recovery symbols with their Merkle proofs such that the decoded sliver does not match the corresponding hash; this proves an incorrect/inconsistent encoding by the client
memberan storage node that is part of a committee at some epoch
permanent blobblob which cannot be deleted by its owner and is guaranteed to be available until at least its expiry epoch (assuming it is valid)
point of availability (PoA)point in time when a CoA is submitted to Sui and the corresponding blob is guaranteed to be available until its expiration
publisherservice interacting with Sui and the storage nodes to store blobs on Walrus; offers a simple HTTP POST endpoint to users
quiltstructured data object consisting of one or multiple unstructured blobs
quilt IDblob ID of a quilt
quilt patcha single blob stored in a quilt, including the unstructured data and metadata
quilt patch IDa unique ID to identify a quilt patch in Walrus; the quilt patch ID is computed from the entire quilt, not a single quilt patch
reconstruction (of a blob)decoding of the primary slivers to obtain the blob; includes re-encoding the blob and checking the Merkle proofs
recoveryprocess of an storage node recovering one or multiple blobs, slivers, or full shards by obtaining recovery symbols from other storage nodes
RedStuffour erasure-encoding approach, which uses two different encodings (primary and secondary) to enable shard recovery; details are available in the whitepaper
shard(disjoint) subset of erasure-encoded data of all blobs; at every point in time, a shard is assigned to and stored on a single storage node
slivererasure-encoded data of one shard corresponding to a single blob for one of the two encodings; this contains several erasure-encoded symbols of that blob but not the blob metadata
sliver pairthe combination of a shard’s primary and secondary sliver
stakerentity that locks (stakes) WAL tokens to support the network's integrity and participate in the selection or validation of storage nodes and committees.
storage challengecryptographic proof mechanism where storage nodes periodically verify each other’s storage of assigned shards by issuing random challenges during storage attestation.
storage attestationprocess where storage nodes exchange challenges and responses to demonstrate that they are storing their currently assigned shards
storage nodeentity storing data for Walrus; holds one or several shards
userany entity/person that wants to store or read blobs on/from Walrus; can act as a Walrus client itself or use the simple interface exposed by publishers and caches
WALthe native Token of Walrus
Walrus-native metadatauser-defined metadata per quilt patch, stored on Walrus together with the corresponding quilt