HTTP range request

How it works

RFC 9110 defines Range and 206 responses. A server that ignores Range forces a restart. A client that stitches ranges must still check the final size and hash. A range on a changing object can mix versions.

A 4 GB download dies at 2.5 GB. The client sends Range starting at that byte and finishes. A server without Range starts over. An object overwritten during the resume mixes old and new bytes. The hash catches it.

How it differs

Range is a download tool. Multipart upload is the upload-side analogue, not the same header.

A proxy that strips Range silently disables resume.

Test a mid-file continue.

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 http range, 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 http range 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.