Decentralized Bridges

The Quai Network utilizes coincident blocks created from merged mining to transfer state across blockchains. As a lower blockchain's security is validated in the Prime blockchain, hashlinks become available to be traced and transferred. These hashlinked block sets are rolled up and applied to the state of the receiving chain. Since all work is being validated through Prime, we can trustlessly transfer the rolled up transactions with certain assumptions of correctness.

External Transactions

External transactions, which will now be referred to as a ETx(s), are transactions that modify state across Quai Network blockchains. An example of an ETx is a Tx that sends QUAI from Region 0 Zone 0 to Region 1 Zone 3. This ETx will need to be recorded via the UTXO connector in Region 0, Prime, and Region 1 before ultimately modifying state in Zone 3. ETxs are separated by address state. Quai utilizes separated address spaces dictated by the first two bytes of an address to split the originating location of where funds can be sent from.

External Block

An External Block is a block that contains transactions specifically for one context. The External Block is generated in the manager and is sent to the node to be stored in the cache. The External Block contains only External Transactions and is utilized in the TraceBranches method in order to apply the transactions upon a coincident block.

Example Zone to Zone Transaction through Region

In the below example, a transaction is sent from Cyprus 1 to Cyprus 3 in the following steps:
  1. 1.
    A Transaction is created in Cyprus 1.
  2. 2.
    A coincident block with Cyprus and Cyprus 1 occurs, creating the hashlink to retrieve the transaction in Cyprus 1 from Cyprus.
  3. 3.
    A coincident block with Cyprus and Cyprus 3 occurs, creating the hashlink to retrieve the transaction in Cyprus 3 from Cyprus 1 through Cyprus.