Instead of chasing dangerous "patched" files, consider:
A patched firmware forces changes. A command unlock is safer. Many F601s on old firmware have hidden Telnet ports. zte f601 firmware download patched
Note: If these commands do not work, ZTE patched the Telnet vulnerability. This is why people search for newer patched firmware—to re-open the Telnet door. Instead of chasing dangerous "patched" files, consider: A
A few enthusiasts modify F601 firmware to make the ONT behave like an SFP module on a switch/router – essentially turning a $10 ONT into a $200 "GPON stick." This often breaks the device. Note: If these commands do not work, ZTE