> ## Documentation Index > Fetch the complete documentation index at: https://cts-docs.cosmos.network/llms.txt > Use this file to discover all available pages before exploring further. # Overview > How the Cosmos Tokenization Suite integrates with digital asset custody providers so banks can hold and move digital assets with bank-grade controls. The Cosmos Tokenization Suite (CTS) lets a bank issue tokenized deposits on its own digital ledger of its choosing, keep those tokens synchronized with the core banking system, and move value to counterparties on other networks. Moving value beyond the bank's own ledger means holding and transferring digital assets on networks that other parties can also access. Custody is how the bank does that safely. CTS integrates with a digital asset custody provider that the bank has already selected and diligenced. Asset safekeeping, key security, governance controls, and regulatory cover come from that custodian. Without this integration, the bank would have to build and maintain that stack itself. ## Two custody functions Custody covers two distinct functions, and a deployment can assign them to different parties. Digital asset custody is the holding of the assets themselves. The custodian provides the bank with wallets and addresses it can use for digital assets such as stablecoins used for settlement between banks. It can also custody stablecoins on behalf of the bank's clients and hold other digital asset balances whose positions are reflected on the core. This function can sit with a custody provider or with the bank itself: the Office of the Comptroller of the Currency has confirmed that national banks may provide custody for crypto assets. Key custody and signing is the protection and use of the private keys that control those assets. It covers key generation, storage, rotation, and the enforcement of the bank's signing policy before any transaction is broadcast. This function usually sits with the custody provider, but a bank can perform it with its own hardware security modules. CTS never holds private keys in either arrangement. The two functions often come from the same provider, but they do not have to. A bank can custody its own digital assets while a provider performs signing, or hold its own keys for assets a provider safekeeps records for. ## Division of responsibility | Layer | Owner | Responsibility | | ----------------------------- | ----------------------------- | --------------------------------------------------------------------------------------------------------- | | Core banking | Bank | Records of record for client deposits, balances, and reconciliation | | Tokenization and coordination | CTS | Running the digital ledger, coordinating payments with counterparty banks, tracking interbank obligations | | Digital asset custody | Custody provider or bank | Wallets and addresses holding settlement assets, client stablecoin balances, and other digital assets | | Key custody and signing | Custody provider or bank HSMs | Generating and protecting private keys, enforcing signing policy, broadcasting settlement transactions | | Settlement network | Blockchain | Finality for the settlement asset transfer | CTS calls the custodian through its API when a transaction needs to be signed. The custodian applies the bank's own approval policy before signing. This ensures that governance controls for a treasury movement continue to apply when that movement happens on chain. ## Where custody appears Custody is invoked by three applications. The pattern is the same in each case: a custody provider is used whenever private keys are needed to hold or transfer digital assets on a network that an external party can also access. Settlement assets held in custody settle the gross interbank obligations that accumulate as client payments clear. External assets held in custody are moved under policy, on schedule or in response to on-chain conditions. What CTS expects from a custody provider and how an existing provider is wired in. ## Why not self-custody A bank can custody its own digital assets and hold its own keys, and CTS supports both. In practice, most banks integrate a custodian for reasons that sit outside the technology: * Qualified custody may be required by the bank's regulator for certain asset classes * Insurance and loss coverage is easier to obtain against a custodian's controls * Key ceremony, hardware security module operations, and staff segregation are expensive to run to audit standard * A custodian already supports the settlement networks the bank needs, so adding a network is a configuration change rather than an engineering project See [Key Security and Governance](/digital-asset-custody/key-management) for what the bank retains control over in either case.