# Architecture KSI is a filter created to run within the Kroxylicious Kafka proxy (). The filter utilises an embedded or external Iceberg engine to fetch data before reformatting it for Kafka purposes.
A typical flow may look like this: 1. Kroxylicious receives a FETCH request for offsets that are stored in Iceberg not Kafka 2. This satisfies the routing config in Kroxylicious and so the request is intercepted by the K.S.I. filter 3. In parallel the filter: 1. Fetches data matching the request from Iceberg using a provided Iceberg engine 2. Fetches the appropriate schema of the data of the data from Schema Registry 3. Launches a pre-fetch task to fetch the next chunk of data from Iceberg (K.S.I. expects sequential access by Kafka clients and can greatly increase performance by fetching data to satisfy future requests ahead of time). 4. K.S.I. encodes the Iceberg data into Kafka message format 5. The K.S.I. filter passes the encoded response back to Kroxylicious to return to the client. --- # 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.streambased.io/deploy-and-operate/streambased-platform/kafka-service-for-iceberg-k.s.i./architecture.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.