Data Models

This page describes key data structures used in Kaspeak SDK for forming, sending, and receiving messages.

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Payload Structure

Payload is a data structure embedded in a Kaspa transaction. Each payload contains the actual data and necessary metadata.

Payload always starts with a unique KSPK marker (0x4B53454B).

Payload Format

Offset	Field	Size	Description
0	marker	4	Marker KSPK (SDK identifier)
4	version	1	Protocol version (currently = 1)
5	prefix	4	Application prefix (ASCII)
9	type	2	Message type (messageType)
11	id	33	Message identifier (Identifier)
44	publicKey	33	Sender's public key
77	signatureType	1	Signature type (1 = single, 2 = multi)
78	signature	64	Payload's Schnorr signature
142	dataLen	2	Data length (bytes)
144	data	N	Data (CBOR, compressed, possibly encrypted)

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Peer Object

Peer describes the message sender and stores the public key and shared secret for encrypted messages.

Peer fields:

Field	Type	Description
address	string	Sender's Kaspa address
publicKey	Uint8Array	Sender's public key
signature	Uint8Array	Schnorr signature of payload
isOwn	boolean	true if the message sent by SDK itself
sharedSecret	Uint8Array	Shared secret (encryption key)
chainKey	bigint	Scalar for generating message ID chains

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Identifier and SecretIdentifier

Cryptographic message identifiers ensure privacy and message linkage within conversations.

Identifier

A compressed secp256k1 curve point uniquely identifying a message without revealing order externally.

Field	Type	Description
hex	string	Hex representation of a point (66 characters, compressed format)
bytes	Uint8Array	Binary representation of an identifier (33 bytes)

Methods:

• fromHex(hex) / fromBytes(buf)
• fromChainKey(chainKey, i, PK)
• next(chainKey, n) / prev(chainKey, n)
• verify(sig, msg)

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SecretIdentifier

Extends Identifier by adding a private key (scalar) for creating signatures.

Field	Type	Description
secret	bigint	Private scalar for signing messages

Optional methods:

• sign(msg) - creating a Schnorr signature of a message using a secret key.

Important: SecretIdentifier cannot be created from public data. Use factories:

• SecretIdentifier.fromSecret(secret)
• SecretIdentifier.random()

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MessageHeader Object

MessageHeader contains all necessary message information.

MessageHeader fields:

Field	Type	Description
txid	string	Kaspa transaction ID
peer	Peer	Sender information
prefix	string	Application prefix
type	number	Message type
identifier	Identifier	Message identifier
blockMeta.hash	string	Hash of the block in which the transaction was confirmed
blockMeta.timestamp	bigint	Confirmation time (Unix-time)
blockMeta.daaScore	bigint	Kaspa network complexity index (DAA)
consensusHash	string	Consensus hash (signed data)