# Existing Technology There have been existing technologies that attempted to solve the problem of blockchain inter-communication and interoperability. These projects, although pursuing dissimilar goals, have all produced alternative solutions to this particular problem. While the solution proposed by AERO is a novel overarching solution that differs in functionality and application from these existing technologies, we can find merit in discussing these technologies in comparison to AERO. Some of these existing technologies include Polkadot, Aion, Sidechain, Cosmos, Interledger, and VirtualChain The communication level proposed by AERO will take place over the transaction level, as is seen with the VirtualChain architecture. In comparison, Interledger and Sidechain favor a transaction level communication protocol, while Cosmos, Aion, and Polkadot all use a protocolbased transaction level for legacy levels. Cosmos, Polkadot, and Aion shared another similarity in interoperability Both the existing technologies and the AERO deploy a two-phase commit connection method. However, the major differences lie in their connection speeds. Interledger uses notaries and entity consensus while Virtualchain focuses on migration time. Cosmos connection speed is proportional to the number of validators, Aion’s and Polkadot’s are dependent on the protocol time, and Sidechain uses its confirmation and contest period. For AERO connection speed, a flexible protocol time dependent approach is favored. --- # 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://aero-protocol.gitbook.io/whitepaper/existing-technology.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.