Client-to-server transfer

How it works

This is the normal shape. The server has the stable address. The client may be a browser, an SFTP binary, or a script. Completion is the server's byte count for an upload, or the client's for a download.

A laptop SFTP-puts a 2 GB export to a partner host and checks remote size. The laptop can then sleep. The server keeps the file. A direct laptop-to-laptop copy would have required both awake.

How it differs

Client-to-server is not server-to-server. A person or a user agent is on one side.

A client that reports success before the server ack will lie on a dropped connection.

Wait for the ack.

On the ticket

• The practical close is a log line: time, actor, byte count, result.
• Without that line the transfer is a story.
• With it, the next person can see whether this door did what the ticket claimed.
• If the path is shared, say so in the partner profile so a later change does not silently pick a different limit, key, or region.
• On a real ticket, write down the door, the byte count, and the clock.
• For client to server transfer, that means naming the host or bucket, the expected size, and the time the other side must have a complete file.
• A progress bar is not that record.
• A 200 response that arrives before the complete call is not that record.
• If a retry is allowed, say how many and whether it resumes.
• If a person must approve the send, name the person.
• Partners who receive client to server transfer files should match on hash or size before they import.
• A same-length corrupt file passes a size check and fails a hash.
• Keep the published hash off the only channel an attacker can edit, or treat it as a corruption check rather than a substitution check.
• When the path changes, new key, new region, new cap, update the profile the same day so the next run does not use a stale limit.