Solana: Address Lookup Table is not compressing addresses as expected

A recent transaction on the Solana blockchain has highlighted an issue with the address lookup table, which is a critical component of the network’s decentralized finance (DeFi) ecosystem. The problem arises when a user attempts to view their own address in the Solana Explorer.

The Transaction

On December 2nd, a developer shared a transaction on the Solana blockchain explorer, Explorer.Solana.com, that showcased an issue with the lookup address table. Specifically, the transaction involved sending a transaction with the following details:

• Transaction ID

  

  : 5FvqJxfoffeBGMwQHh618KzZcNSHCmfdvY4xwNJBsSDyfNEqWpJ9R1FZSWRccyKkrsUDt4ZG3YaZEdvmawHSPT2X

• Cluster: devnet

The Issue

Upon reviewing the transaction, it became apparent that the lookup address table was not compressing addresses as expected. In Solana, addresses are typically represented in a specific format that includes a checksum of the entire address, which is used to validate the authenticity and integrity of the transaction. However, when this checksum is calculated for an address, it does not always match the original address.

The Problem

The problem arises from the fact that the lookup address table uses a simple hash function to calculate the checksum of each address. While this approach may seem sufficient in many cases, it is not robust enough to handle certain types of addresses or edge cases. Specifically:

• Single-Character Addresses: When using a single-character address (e.g., abc), the lookup address table does not correctly compute the checksum.

• Address Extensions

  : Some Solana addresses have extensions that require additional data, which can be lost when computing the checksum.

Conclusion

The issue with the address lookup table on Solana is an important one to highlight. While the blockchain’s design has many strengths, its reliance on a simple hash function for calculating checksums can lead to errors and inconsistencies in certain cases. Developers and users should be aware of this potential issue when working with addresses on the Solana network.

Recommendations

To mitigate this problem, it is recommended that developers:

• Use more robust address formats, such as multi-character addresses or addresses with extensions.

• Implement additional checks to verify the integrity of the address before using it for transactions.

In addition, users should be cautious when working with addresses on the Solana network and consider seeking help from experienced developers or Solana experts if they encounter any issues related to address lookup tables.