# How it Works
StreamDuo is designed around the concept of a "stream" which is a private data channel to share data with your external partners.
A "stream" is similar to an SFTP server or MFT (Managed File Transfer) service in the sense that you can manage and control accesses, but the big difference with StreamDuo is that it is designed and optimized for the transfer of Structured Data. Catering to the use of data engineers moving structured data between external partners.
The 3 Key features that make StreamDuo better for structured data are:
# Built for Automation
Users are able to provision machine clients unique to each stream, and scoped to the operations needed (read or write). This is ideal for automated processes, and avoids the use of user credentials in automated processes.
# Schema Hosting and Enforcement
SFTP servers are a free-for-all when it comes to data quality, files are never checked for data accuracy, and bad data (empty files, corrupt data) sneak into your pipeline.
StreamDuo allows you to set a data schema for your stream and define quality rules that are enforced upstream before the upload even happens.
Set your data quality rules as a JSON schema, Great Expectations, or AVRO schema.
# Integrated Encryption Key Management
End-to-end encryption is essential for sensitive data. Exchanging public keys over email or performing a key rotation, is a challenge for transfers done over traditional SFTP.
StreamDuo hosts public keys for you streams so when sending data, the proper public key is always used for encryption. Data is always encrypted with the latest active key.