I can, my Internet went out Friday about 9:30PM and didn't come back until about 12 hours later, still had my Network and access from different computers [Wired and Wireless] to the Mapped Public folder and its subfolders on my NAS drive and to the 2 printers connected to it. The Internet is accessed through the Wireless DSL PoE Modem connected to the Uplink port on the Router. The Modem is separate from the Router with its own power cable, pulling that turns the Modem off.
My router is at the opposite end of the house. I do have an 8 port Ethernet switch where my computers are. That power is controlled by a light switch as I enter or leave the room. If that "harms the switch" they are pretty cheap. So far 6 years on the current one. Router runs 24/7 in the mean time.
When you set a rule in the router to block a computer o device to be able to go online, it still has local lan access, so yes you should be able to log in to the router then.
I dont know how good consumer routers is nowadays, but i think they has that function to block devices to be able to go out on WAN..
I have not used consumer network products since 2003 or 2006.. i dont remember the year exactly.... a long time anyway.. so I'm kind of out of the loop on consumer products.
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