Trust-based bridges, also known as custodian-based bridges, are a type of bridge that relies on intermediaries or custodians to hold and manage assets. Here are some key characteristics:

1. Centralized: Trust-based bridges are typically centralized, meaning that a single entity or a small group of entities control the bridge.

2. Custodial: Assets are held by a custodian, which can be a centralized exchange, a bank, or another type of financial institution.

3. Trust required: Users must trust the custodian to securely hold and transfer their assets.

4. Counterparty risk: Users are exposed to the risk of the custodian failing or acting maliciously.

5. Regulatory compliance: Trust-based bridges are often subject to stricter regulatory requirements, as they are considered financial institutions.

6. Examples: Centralized exchanges, custodial services, and banks that offer asset transfer services.

While trust-based bridges can offer convenience and ease of use, they also present risks and limitations, such as counterparty risk and centralization.