if uve seen this meme and didnt get why the waifu has that angry face, stick with me and ill explain everything ( ≧▽≦)
putting a static ip inside the dhcp range is one of those things that looks harmless but will break ur whole network and u wont understand why. and the worst part is the sensei in the meme probably thinks hes doing it right (´；ω；`)
what dhcp actually is
imagine the router is the owner of a hotel. dhcp is like the automatic system that owner uses to give a room key to the guest who just arrived.
the guest doesnt choose the room number, the system just hands over one thats free at the moment. if room 101 is occupied, it gives 102. if 102 is also occupied, it gives 103. its all automatic and the guest doesnt need to worry about anything ( ´ ▽ ` )
on the network, this works exactly like that. ur phone gets home, connects to wifi and says "hey router, i need an ip". the router looks at its list and replies "alright, heres 192.168.1.15". ur phone didnt choose this number, it just got what was available at the time.
and the static ip
now imagine someone decides to pick a fixed room on their own, like "nah i want room 101 and thats final". doesnt matter if its occupied, doesnt matter if the system already reserved it for someone else, this person just goes and grabs the key.
thats the static ip. its when u go into the network card settings and manually type the ip, the mask, and the gateway. the problem is when u do this directly on the pc or phone, it doesnt tell the router "yo, i took this ip for myself ok?"
it just starts using it. and since the router cant guess, it keeps thinking that ip is free in its dhcp list and hands it to another device lol
why it goes wrong when configured inside the range
if sensei configures a device with a static ip thats inside the dhcp list, the router wont know bc its kinda dumb.
heres whatll happen. senseis device joins the network and takes the fixed ip, like room 101. dhcp doesnt notice and delivers that same room 101 to someone elses phone that just arrived. both devices try to use the same spot at the same time.
this causes an ip conflict and the internet on both drops or keeps dropping all the time ( > ﹏ < )
thats why the waifu is fighting with him lol. the right way is to put static ips only outside the range that dhcp manages so this mess never happens.
how to do it right
if sensei wanted his pc to always have the same ip without breaking the network, he had two much cleaner options.
the first is configuring the pc with an ip outside the range. like, if the routers dhcp hands out from 192.168.1.50 to 192.168.1.250, sensei could configure the pc with ip 192.168.1.20 which is safe. that way dhcp will never try to give that ip to anyone.
the second option is making an ip reservation on the router, which is the fancier way. u go into the router page, get the physical address of the pc (the mac address, which is unique in the world) and say "router, every time this pc connects, give it ip x and dont give this ip to anyone else".
the waifu would definitely prefer he did the ip reservation so she doesnt get a headache lol ( *; ω ; * )
but what is a fixed ip even for
keeping a fixed ip for some device has several advantages my friend, but it only makes sense for specific cases. for our regular phone or notebook it doesnt change anything, but its super important for some network stuff (｡• 💻 •｡)
one of the biggest uses is finding the device easily on the network. imagine u have a wifi printer or a file server at home. if its ip kept changing every time the router restarted, ur pc wouldnt be able to find it to print bc the address changed lol. with a static or reserved ip, the address is always the same, so the connection never gets lost.
another case is opening ports for games and servers. if u play something that needs to create a server like minecraft or terraria, sometimes u need to open ports on the router so people can connect to ur pc. the router needs to know exactly which ip to send the data that comes from the internet. if ur ip changes, the open ports will point to the wrong place and the server goes down.
in companies, network admins use fixed ips to know exactly who is who. like "ip 192.168.1.10 is the main server, .11 is the hallway camera". way easier to monitor if something breaks or block weird access.
thats why sensei wants to use a static ip, his only mistake is the dumbness of not isolating that ip from the rest of the dhcp so the conflict we talked about doesnt happen ( ^ ▽ ^ )
now when u see someone configuring a static ip inside the dhcp range, u can send them this article and save their network before it turns into a mess~