Transactions on a blockchain are packaged into blocks. Different blockchains have different rules for how to decide which transactions get packaged into a block, but they often include rules for invalidating recently generated blocks.

Reorganization of Transactions

This rewrite of history is called a reorganization and invalidates any transactions included in the invalidated blocks. This means that upon a reorganization the invalidated transactions never happened.

Such events can represent a potential security risk, because an malicious intruder could use an on-chain transfer as payment for a good or service, and subsequently tries to trigger a reorganization which would invalidate the transfer (returning the cryptocurrency or asset) while keeping the good or service "paid" for.

Block Confirmations

A way to protect against reorganization attacks is to wait for a number of confirmed blocks before recognizing a transaction as final on the blockchain. The more blocks that are processed on a blockchain after a given block, the more difficult it will be with that the block may be invalidated. Therefore, by choosing how many blocks to wait before recognizing a transaction, the receiver is able to balance speed and security.

The confirmation number is the number of blocks you wait before considering a transaction as final, which is typically different for different chains. StablR uses the following confirmation numbers for its supported chain.