> For the complete documentation index, see [llms.txt](https://docs.sanko.xyz/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.sanko.xyz/sanko/sanko-overview/data-availability-servers.md).

# Data Availability Servers​

Sanko Data Availability Committee members run Data Availability Server (DAS) software. The DAS exposes two key APIs: the REST API, and the Sequencer API.

* The REST API is a RESTful HTTP(S) based protocol that allows data blocks to be fetched by hash. This API is fully cacheable, and deployments may use a caching proxy or CDN to increase scale and protect against DoS attacks.
* The Sequencer API is a JSON-RPC interface allowing the Sequencer to submit data blocks to the DAS for storage. Deployments will typically block access to this API from callers other than the Sequencer.