A: Yes, but you must first disable version checking. This requires accessing hidden telnet commands (not recommended for beginners).
By preparing a FAT32 USB drive with the correctly named firmware file and using the hardware reset button, you can recover, upgrade, or downgrade your SR120a anywhere—no cloud, no ISP server, no permanent software installation required. fiberhome sr120a firmware portable
However, users frequently search for a specific, elusive concept: If you are a network technician or a tech-savvy homeowner, you might be looking for a way to update your router without an active internet connection, or you may be confusing "portable" with "offline recovery." A: Yes, but you must first disable version checking