As Quai grows, the network can automatically increase its transaction processing power by creating new parallel blockchains. As it grows, your Quai wallet's address belongs to one of multiple Zones (each under one of multiple Regions) on the Quai network.
While processing of transactions is isolated between zones, it's possible to send assets from one zone to another. When sending, you don't have to worry or do anything special. Simply enter the destination address and amount. Koala Wallet will take care of figuring out if the Zone or Region is different or not, and handle everything automatically. You can read more about Quai's shard hierarchy here.
The start of an address (ignoring the "0x" prefix) define which Region and Zone the address belongs to. The first hexadecimal digit defines the Region number (from 0 to F, representing a maximum of 16 Regions) and the second digit defines the Zone number inside that region (also from 0 to F, also a maximum o 16 Zones in a Region). As the network starts with a single Region and Zone, all addresses start with "0x00" to define they belong to the 1st Zone of the 1st Region. As the network grows, an address starting with "0xA8" for example means it belongs to the 11th Region, 9th Zone.
Transaction completion time
The way Quai was designed, transactions will take longer to show up at the destination depending if the source and destination addresses are in the same Zone or Region. Even though Koala Wallet does everything for you, it may be useful to know how long you can expect the transaction to be completed.
The example below shows a network that has grown to have 3 Regions with 3 Zones each.
Transactions to and from the same zone complete within seconds.
Example: 0x02A2... → 0x02C5...
Transactions to a different zone in the same region must first be included in that region's controller shard before confirming at the destination. This add fees and completion time, and can take a few minutes.
Example: 0x00CC... → 0x0191...
Sending to a different region requires the transaction to be included in the Region and Prime shards before it travels back down the hierarchy to the destination zone. This can increase the completion time to dozens of minutes on average.
Example: 0x10F0... → 0x21CB...
If you have balances in multiple shards, Koala Wallet allows you to choose which one to send from. You may choose one that will finalize faster according to the destination address.
In any case, as stated, this entire process is automatic. Any multi-stage transaction requires no special action from the sender. If your transaction is taking longer than expected to confirm, most likely it's cross-zone. You don't have to do anything except be patient.
If the transaction hasn't finalized after more than 2 hours, a technical problem may have occurred. In this case please open a support ticket explaining the issue and including the transaction ID and involved addresses so we can check.