# Dual Data Posting Mechanisms AnyTrust introduces two methods for posting data blocks on L1. Alongside the conventional approach of posting complete data blocks, it enables the posting of DACerts, serving as evidence of data availability. The L1 inbox contract validates DACerts, referencing the specified valid Keyset within each DACert. L2 code, responsible for reading data from the inbox, is engineered to seamlessly handle both data formats. When encountering a DACert, it conducts validity assessments, ensuring the number of signers meets the Keyset requirements, validating the aggregated signature, and confirming that the expiration time extends beyond the current L2 timestamp. Valid DACerts guarantee the accessibility and usability of the data block by the L2 code. --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://docs.roguechain.io/rogue-protocol/rogue-chain/anytrust-revolutionizing-blockchain-infrastructure/dual-data-posting-mechanisms.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.