ONT: I see a lot of used Singtel ONT on Carousell. I want to buy one to keep as spare, because Singtel does not give out ONT anymore. So when (not if) my current ONT breaks down, Singtel can't force me to switch over to ONR. So I want to know is the ONT from someone else's house can work when plugged into my house?
Static IP: Based on my experimenting (plugging a Cisco smart switch into ONT and untagging the VLAN traffic), when I connect two routers, I get two IP addresses assigned by Singtel at the same time (the speed is shared though, tested).
So I am not sure how Singtel assigns the static IP address. Is it based on the house unit number, or the MAC address of the router?
Getting a used ONT would not work. If you ever get converted to ONR, you would need persuasive skills to convince them to configure it in ONT mode. Otherwise find another ISP.
IP address is dynamic. It is randomly assigned based on a pool of IPs. If you turn it off (router) for sometime, you would get a different ip. If you need a fixed static ip, only way is to go for ISPs that offer them such as M1 MR VQ.