What are checksums?
To identify possible mistakes made during data entry or transmission, a checksum is a small piece of data extracted from the original data.
It acts as a distinct fingerprint for data, making it possible to quickly confirm its integrity. Checksums offer a means of confirming that data has been sent or entered precisely, much like the error-correcting codes used in barcodes to ensure accurate scanning.
When a sender computes a checksum for a piece of data, they send the checksum and the data together during data transmission. The receiver uses the same procedure to update the checksum after receiving the data.
Recalculating the checksum and comparing it to the sender’s shows that no changes were made to the data during the transmission. The data might need to be resent if the checksums don’t match, which indicates that errors have happened.
In many applications, such as file storage, network communications and cryptocurrency transactions, where even a small error can cause serious problems, checksums are crucial for ensuring data integrity.
What is an Ethereum checksum address?
Within the Ethereum network, Ethereum addresses act as distinct identifiers for transmitting and receiving cryptocurrency.
The hexadecimal strings representing these addresses are produced using both public and private keys. Ethereum addresses come in two forms: checksummed and non-checksummed. The checksummed version has 42 characters, including capital letters, compared to 40 in the non-checksummed version.
Due to its integrated error-checking feature, which lowers the possibility of funds being sent to the wrong address due to typographical errors, the checksummed version is significant. The so-called “checksum algorithm” is used for the hexadecimal representation of the public key to ascertain the case of each letter in the address when a checksummed address is formed. An address with capital and lowercase letters is the outcome of this technique.
The checksum will fail if the address is typed incorrectly, alerting the sender to the error. Therefore, to ensure transaction accuracy and guard against the loss of funds due to human error, it is imperative that Ethereum addresses be used in their checksummed version.
Which Ethereum improvement proposal introduced checksummed addresses?
Ethereum Improvement Proposal (EIP) 55 introduced checksums to Ethereum addresses.
The inclusion of both capital and lowercase characters identifies checksummed Ethereum addresses.
When transmitting or receiving cryptocurrency, this mix of capital and lowercase letters adds another level of mistake detection. Making checksummed and non-checksummed addresses easily identifiable for users lowers the possibility of inadvertent mistakes occurring during transactions.
However, swapping certain similar-looking letters (like a lowercase “L” = “l” and an uppercase “i” = “I”) might still result in a technically valid checksum. Therefore, users must double-check addresses carefully. Additionally, EIP-55 checksums don’t prevent users from sending Ether (ETH) to a valid but incorrect address. They won’t alert users if they’ve copied an address for a different cryptocurrency by mistake, as address lengths can differ.
How to checksum an Ethereum address
Ethereum addresses are hexadecimal strings of 40 characters, made up of the letters A–F and the digits 0–9. Ethereum utilizes a checksum mechanism to improve accuracy and lower the possibility of errors during transactions.
There are multiple procedures involved in creating an Ethereum address’s checksum. First, a lowercase version of the original address is created. Next, the lowercase address’s Keccak-256 hash is computed. A sophisticated cryptographic algorithm called Keccak-256 generates a distinct hash value given an input.
Next, a comparison is made between each character in the original address and its corresponding bit in the hash. A character is capitalized in the checksummed address if it is a letter (A–F) in the original address and the matching bit in the hash is 1. This procedure makes sure the checksummed address has 42 characters in total, and it uses capital letters to add one more level of error protection.
Ethereum addresses become more resilient to flaws resulting from typographical errors made during transactions by utilizing this checksum technique. It greatly lowers the possibility of funds being transferred to the wrong addresses, giving users on the Ethereum network more security and confidence while sending and receiving cryptocurrency.
Benefits of using checksummed Ethereum addresses
There are various advantages to using checksummed Ethereum addresses, such as improved security, reduced mistake rate and more transparency.
Checksummed addresses greatly lower the possibility of transaction failures. By adding an error-checking feature, they reduce the chance of unintentional loss brought on by typographical errors and assist in transferring funds to the right place.
Moreover, by adding an extra degree of verification, checksummed addresses improve security. By assisting users in identifying and avoiding false or misspelled addresses, the checksum process lowers the possibility of transmitting funds to uninvited or malicious locations.
Furthermore, by giving users confidence, checksummed addresses promote transaction transparency. The knowledge that transactions are less likely to go wrong promotes acceptance of cryptocurrencies and builds confidence in the Ethereum network.
However, it is important to understand that a correctly checksummed address does not guarantee that a corresponding account or contract actually exists on the Ethereum blockchain. To address this issue, a concept of built-in type indicators exists, which enhances clarity and security on blockchains like Ethereum. This system integrates prefixes into addresses to instantly signal the type of entity they represent.
For instance, an address starting with “eoa_” denotes an externally owned account (a standard user’s wallet), while “sc_” signifies a smart contract. This provides immediate clarity, reducing the chance of errors, such as accidentally sending funds to a smart contract instead of an individual’s wallet.
Such indicators help improve users’ experiences with blockchain technology and may lead to wallets and interfaces incorporating security features specific to different address kinds.