: The default "user" account has limited settings. "Fixed" firmware or configuration tools (like the ZTE Config Utility ) help users retrieve the full adminpldt or superuser credentials. 2. Performance & Stability
When the ONT hits the "top" barrier, even if it doesn't reboot, the bufferbloat goes critical. The fixed firmware introduces a rudimentary Active Queue Management (AQM) that keeps the ICMP (ping) packets ahead of the CPU queue. zte f670l v90 firmware fixed top