This topic provides answers to some commonly asked questions about URL signing for live streaming. When do I need to use URL signing? How do I configure URL signing? What do I need to take note of when I use URL signing? Can I modify the expiration timestamp of a signed URL?Can I share a live stream with others by using a QR code?Can I set a signed URL for multiple streaming domains?Does ApsaraVideo Live provide an API operation for URL signing?