# TSN

- [TSN: Identity-First Settlement for Stablecoins on Solana](https://trust-link-tsn.mintlify.app/overview/introduction.md): TSN is an identity-first, intent-based, privacy-preserving settlement layer for stablecoin and digital asset transfers, built on Solana by TrustLink Labs.
- [How a TSN Payment Feels: One Action, Many Checks](https://trust-link-tsn.mintlify.app/how-it-works/how-a-payment-feels.md): A TSN payment looks like one action to the user. Under the hood, TIN, GPRU, TSN, and TCAP cooperate. This page shows both views side by side.
- [TSN Current Architecture: TIN, GPRU, Epoch Treasury, TCAP](https://trust-link-tsn.mintlify.app/how-it-works/architecture.md): The canonical Transfer Settlement Network architecture: TIN identity, GPRU authorization, TSN epoch treasury with Mother-rooted DNA permits, and TCAP tip credits.
- [TSN FAQ: Privacy Boundaries, Deployment Status, TCAP](https://trust-link-tsn.mintlify.app/get-started/faq.md): Common questions about the Transfer Settlement Network by TrustLink Labs: privacy boundaries, deployment status, TCAP, TIN, GPRU, and the debit gate.
- [TSN Layer: Settlement Coordination and Epoch Treasury](https://trust-link-tsn.mintlify.app/layers/tsn.md): The TSN settlement layer: epoch treasury, Mother-rooted DNA permits, opaque EpochClaimSlot PDA, and cranker vault reimbursement.
- [TIN Layer: Transfer Identity Number and Route Discovery](https://trust-link-tsn.mintlify.app/layers/tin.md): TIN is the 10-digit Transfer Identity Number issued by the Transfer Identity Protocol. It resolves payment routing without exposing a wallet address.
- [GPRU Layer: Non-Custodial Authorization and Routing](https://trust-link-tsn.mintlify.app/layers/gpru.md): GPRU is scoped authorization and routing for TSN transfers. It carries permissions, commitments, expiry, and replay material, but never holds funds.
- [TCAP Layer: Credit, Debit, and Exit (Confidential Balances)](https://trust-link-tsn.mintlify.app/layers/tcap.md): TCAP is the Transfer Confidential Asset Protocol: commitment-backed tip credits, gated confidential debit and exit, and encrypted balance snapshots.
- [Current TSN Architecture: Solana-First Payment Settlement](https://trust-link-tsn.mintlify.app/overview/architecture.md): Explore TSN's five-layer identity-first architecture on Solana, from identity and routing through intent-based, privacy-preserving settlement.
- [Why TSN Separates Authorization from Transaction Submission](https://trust-link-tsn.mintlify.app/overview/separation-of-concerns.md): Learn how TSN splits authorization, verification, and submission across distinct roles for safer, more resilient payments.
- [TSN Trust Model: Authorization vs. Transport Boundaries](https://trust-link-tsn.mintlify.app/architecture/trust-model.md): Learn how TSN splits authorization (sender intent and Mother-rooted receipts) from transport (Receiver, Node, Cranker) and what each role can and cannot do.
- [TIN and GPRU: Identity and Non-Custodial Routing](https://trust-link-tsn.mintlify.app/architecture/identity-and-routing.md): How TSN resolves payment identity through the 10-digit TIN issued by TIP, and how GPRU carries authorization and routing without ever holding funds.
- [Mother Authority and Opaque Epoch Slots](https://trust-link-tsn.mintlify.app/architecture/mother-authority.md): Learn how Mother Escrow coordinates epochs, materializes the one-time SettlementDna PDA, and enforces atomic settlement or refund through opaque slots.
- [Receiver, Node, and Cranker: Separation of Transport](https://trust-link-tsn.mintlify.app/architecture/node-receiver-cranker.md): Learn how the Receiver, Node, and Cranker divide durable ingress, stateless verification, and exact transaction submission without sharing secrets or altering plans.
- [Epoch Treasury: Protocol Liability Accounting](https://trust-link-tsn.mintlify.app/architecture/epoch-treasury.md): Learn how the Epoch Treasury records aggregate funding and settlement liability using opaque slots and why it is protocol-controlled accounting, not a user balance.
- [TCAP: Transfer Confidential Asset Protocol](https://trust-link-tsn.mintlify.app/architecture/tcap.md): TCAP provides private GPRU balance transitions on Solana using blinded tip PDAs and owner-encrypted balance snapshots.
- [TSN Protocol Invariants: What Must Always Hold](https://trust-link-tsn.mintlify.app/security/invariants.md): The 11 protocol invariants TSN and TCAP enforce on Solana: signed field binding, single-consume slots and nullifiers, sequence monotonicity, and commitment binding.
- [TSN Threat Model: Adversary Classes and Guarantees](https://trust-link-tsn.mintlify.app/security/threat-model.md): TSN adversary classes: compromised Receiver, Node, Cranker, network observer, malicious sender or recipient. What each can achieve and what stays protected.
- [TSN Authority and Key Material: Who Holds What](https://trust-link-tsn.mintlify.app/security/authority-and-keys.md): Every key and credential in TSN: sender wallet, TIN owner commitment, Node permit, Mother authority, encrypted binding, and owner snapshot key. Includes owner, authorization scope, and rotation model.
- [TSN Fail-Closed Design: Reject Before Any Token Moves](https://trust-link-tsn.mintlify.app/security/fail-closed.md): TSN fails closed: any failed check rejects the operation with no partial settlement. Learn the ordered checks from Receiver ingress through Solana program enforcement.
- [TSN Replay Protection: Nullifiers, Sequence, and Slot Windows](https://trust-link-tsn.mintlify.app/security/replay-protection.md): How TSN prevents replay attacks using nullifiers, strictly increasing sequence, Solana slot windows, signed-field binding, and first-valid-wins epoch slots.
- [TSN Operator Boundaries: Data Visibility Per Role](https://trust-link-tsn.mintlify.app/security/operator-boundaries.md): What each TSN operator can see, send, and modify. Covers sender, Receiver, Node, Mother, Cranker, and Solana program boundaries with a worked attack example.
- [Get Started with TSN: Sign, Submit, and Settle on Devnet](https://trust-link-tsn.mintlify.app/developers/getting-started.md): Set up Solana tooling, register a TIN, sign a payment intent, and submit it to the TSN Receiver on Devnet. Follow the complete path from SDK installation to on-chain confirmation.
- [Use a Private TIN in a TSN Payment App](https://trust-link-tsn.mintlify.app/developers/private-tin-issuance.md): Build a privacy-aware payment experience with the TSN SDK without exposing TIN secrets to application servers or settlement operators.
- [Check TSN Network Status Before Signing](https://trust-link-tsn.mintlify.app/developers/network-status.md): Use the TSN SDK to select reachable services and prevent an application from creating a transaction while settlement dependencies are unavailable.
- [Payment Intent Lifecycle from Signature to On-Chain Settlement](https://trust-link-tsn.mintlify.app/developers/payment-intent-lifecycle.md): Follow a TSN payment intent through every state from signed canonical message to Solana confirmation. Understand redaction, verification checks, and what each role sees.
- [TSN Epoch Treasury Funding and Accepted Intent Flow](https://trust-link-tsn.mintlify.app/developers/funding-and-accepted-intent.md): Learn how TSN epoch treasury funding works, how the AcceptedIntent PDA binds fields, and how opaque slots settle or refund atomically on Solana.
- [TSN Confidential Settlement via TCAP Credit Path](https://trust-link-tsn.mintlify.app/developers/confidential-settlement.md): Understand the live TSN to TCAP credit path, the ConfidentialSettlement ABI fields, and how the TSN CPI wrapper ensures authorized commitment transitions.
- [TCAP Tip Credits and Commitment Transitions](https://trust-link-tsn.mintlify.app/developers/tcap-tip-credits.md): Learn how TCAP tip state PDAs track private balance commitments, how credit-only transitions work, and how encrypted snapshots bind to the on-chain sequence.
- [Replay Protection and Safe Retry Patterns in TSN](https://trust-link-tsn.mintlify.app/developers/replay-and-retries.md): Understand how TSN prevents double spending using replay nonces, nullifiers, slot windows, and sequence monotonicity. Learn safe retry patterns for settlement failures.
- [API Reference — Public TSN surfaces](https://trust-link-tsn.mintlify.app/api-reference/index.md): Source-backed reference for TSN APIs, SDK exports, operator commands, and Solana entrypoints used to build DESP applications.
- [Authentication — Authenticate TSN service calls](https://trust-link-tsn.mintlify.app/api-reference/authentication.md): Use worker API keys for privileged TSN calls and public signed payloads for application intents without exposing private settlement data.
- [Errors — TSN response and failure codes](https://trust-link-tsn.mintlify.app/api-reference/errors.md): Reference the HTTP and JSON-RPC failures currently emitted by TSN services when authentication, validation, routing, or upstream work fails.
- [Node API — TSN mempool and route endpoints](https://trust-link-tsn.mintlify.app/api-reference/rpc/node.md): Use the TSN Node REST surface to submit signed intents, inspect routes, lease worker work, and observe settlement state.
- [RPC Gateway — Solana JSON-RPC and health](https://trust-link-tsn.mintlify.app/api-reference/rpc/solana-rpc-gateway.md): Send Solana JSON-RPC through the TSN gateway and inspect provider health without exposing upstream credentials to applications.
- [TSN SDK — Build signed settlement clients](https://trust-link-tsn.mintlify.app/api-reference/sdk/tsn-sdk.md): Use the TypeScript SDK to build intents, inspect service status, resolve private TIN routes, and validate cross-chain settlement data.
- [Cranker SDK — Submit authorized TSN work](https://trust-link-tsn.mintlify.app/api-reference/sdk/tsn-cranker-sdk.md): Use the Cranker SDK's on-chain helpers to initialize operator state, register a Cranker, fund its vault, and manage protocol setup.
- [resolveTIN — read a TIN account from Solana](https://trust-link-tsn.mintlify.app/api-reference/sdk/tins/resolveTIN.md): Reads a TIN account, decodes its identity route, and reports whether the stored record is ready for current TSN settlement use.
- [resolveTinRoute — Read a TIN payment route](https://trust-link-tsn.mintlify.app/api-reference/sdk/tins/resolveTinRoute.md): Resolve a TIN through the SDK and return the route commitments that a signed payment must bind before authorization and submission.
- [createTinV1IdentityEnvelope — Encrypt a TIN identity](https://trust-link-tsn.mintlify.app/api-reference/sdk/tins/createTinV1IdentityEnvelope.md): Create the encrypted identity envelope and lookup commitment accepted by the legacy CreateTinV1 registry instruction.
- [buildCreateTinInstruction — disabled direct TIN builder](https://trust-link-tsn.mintlify.app/api-reference/sdk/tins/buildCreateTinInstruction.md): Checks the direct TIN creation boundary and currently fails closed so applications cannot bypass TSN Node and Cranker authorization.
- [buildLinkSocialIdentityInstruction — Link social identity](https://trust-link-tsn.mintlify.app/api-reference/sdk/tins/buildLinkSocialIdentityInstruction.md): Encode an encrypted social identity link for a TIN registry transaction without exposing the plaintext identity value.
- [buildLinkVerifiedSocialIdentityInstructions — Link proof](https://trust-link-tsn.mintlify.app/api-reference/sdk/tins/buildLinkVerifiedSocialIdentityInstructions.md): Build the Ed25519 proof and TIN registry instructions needed to link a platform-verified encrypted social identity.
- [buildLinkSensitiveFieldInstruction — Link sensitive field](https://trust-link-tsn.mintlify.app/api-reference/sdk/tins/buildLinkSensitiveFieldInstruction.md): Build the TIN registry instruction that stores an encrypted sensitive field bound to a user authorization hash.
- [encryptTinSocialIdentity — Encrypt social identity](https://trust-link-tsn.mintlify.app/api-reference/sdk/tins/encryptTinSocialIdentity.md): Encrypt a social identity locally with an AES-GCM key derived from the TIN and return the nonce and ciphertext for linking.
- [decryptTinSocialIdentity — Decrypt social identity](https://trust-link-tsn.mintlify.app/api-reference/sdk/tins/decryptTinSocialIdentity.md): Decrypt a TIN social identity locally with the same derived AES-GCM key and return the plaintext only to the caller.
- [encryptTinSensitiveField — Encrypt sensitive field](https://trust-link-tsn.mintlify.app/api-reference/sdk/tins/encryptTinSensitiveField.md): Encrypt a TIN-sensitive field locally with a signature-derived AES-GCM key and return its authorization hash.
- [decryptTinSensitiveField — Decrypt sensitive field](https://trust-link-tsn.mintlify.app/api-reference/sdk/tins/decryptTinSensitiveField.md): Decrypt a TIN-sensitive field locally after deriving the same key from the TIN, field type, and user signature.
- [decodeTinAccount — decode a TIN account](https://trust-link-tsn.mintlify.app/api-reference/sdk/tins/decodeTinAccount.md): Decodes the serialized legacy TIN account bytes into its stored identifier, display name, encrypted fields, and route commitments.
- [decodeTinsIdentityRegistry — Decode TIN registry bytes](https://trust-link-tsn.mintlify.app/api-reference/sdk/tins/decodeTinsIdentityRegistry.md): Decode a serialized TIN identity registry account into typed identity, social-link, and sensitive-field records.
- [tsn-cranker — Configure an operator](https://trust-link-tsn.mintlify.app/api-reference/cli/tsn-cranker.md): Run the supported TSN Cranker SDK setup commands with a local signer, gateway RPC, and the required token-account arguments.
- [Solana Entrypoints — TSN protocol instructions](https://trust-link-tsn.mintlify.app/api-reference/on-chain/solana-entrypoints.md): Reference the Solana program entrypoints that create TIN state, authorize settlement, manage Crankers, and preserve TSN accounting boundaries.
- [Mother Node: Verification and Authorization Boundary](https://trust-link-tsn.mintlify.app/operators/tsn-node.md): The TSN Node verifies signed intents, coordinates the epoch treasury, holds encrypted payment bindings, and signs Mother-rooted DNA permits.
- [Cranker Node: Lease, Submit, and Pay Fees](https://trust-link-tsn.mintlify.app/operators/tsn-cranker.md): A Cranker Node leases Mother-Node-verified work, submits the exact authorized transaction, and pays network fees without changing settlement terms.
- [TrustLink Labs: Building Open Payment Infrastructure](https://trust-link-tsn.mintlify.app/about/trustlink-labs.md): TrustLink Labs builds TSN, TIN, GPRU, TCAP, and TrustLink Pay. Learn the mission, engineering approach, and how the protocol components fit together.
- [What TrustLink Labs Is Building: Protocols and Products](https://trust-link-tsn.mintlify.app/about/what-were-building.md): Concrete artifacts from TrustLink Labs: TSN protocol, TIN registry, GPRU authorization, TCAP credit-only transitions, TrustLink Pay reference app, and TSN SDK.
- [TrustLink Labs Engineering Principles](https://trust-link-tsn.mintlify.app/about/engineering-principles.md): Four principles guide TrustLink Labs: privacy by architecture, user ownership, verifiable execution, and modular open infrastructure.
- [Current TrustLink Technology on Solana Devnet](https://trust-link-tsn.mintlify.app/about/current-technology.md): What is live on Solana Devnet today: TSN intents, TIN registry, GPRU routing, Mother Escrow, Node verification, Cranker submission, Epoch Treasury, TCAP credit-only transitions, and encrypted snapshots.
- [Contribute to TrustLink Labs: Research, Code, and Docs](https://trust-link-tsn.mintlify.app/about/contribute.md): How to contribute to TrustLink Labs protocols, research, and reference applications. Links to GitHub repos, research library, TSN blog, and X.
- [Community and route governance](https://trust-link-tsn.mintlify.app/about/community-and-governance.md): How the TSN community evaluates and expands settlement routes.