1. im not from globe, pero based sa experience ko with the same model ng PLDT fiber..
in your type of modem... (one) 1 port can only used thru/to/by LAN (if im correct its LAN1)...
other ports (the remaining 3 ports) are reserved...
2. AP isolation settings
my problem naman.. can not access superadmin.. can you PM me its user/pass
(but i have different modem.. ) will try sana what you have found out...
I had similar problems - until I found that the router has a basic firewall enabled by default.
Ok a firewall is a good thing but this one blocks ethernet ports - after I switched the routers internal firewall to OFF I can use the ethernet ports !