this post was submitted on 17 Mar 2026
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For the uninitiated, the joke is:
spoiler
Each number should has a maximum value of 255.The fact that I have a test in school today, and this is probable questiom in it, and this post reminded me of it, thanks I guess?
EDIT: wait, so each number should be maximum of 255? Why did I think it was just the last numbe :|
anyway thanks again for the unsolicited coincidental heads up
Each number between the dots is made up of 8 bits, so each one is a maximum of 255.
Update, they didn't ask that questiom. For the exam XD
Hope it went well!
It did, I mean it was a computer science test which was easy (I help the computer teachers to solve stuff in school lol)
I'm still angry even 15 years later after a teacher lowered my grade just because I checked "USB" as capable technologies for video transmission. There are literally USB monitors.
Granted, back then it really wasn't popular and bandwidth was shit, but it was capable of it.
USB to VGA dongles were definitely a thing over 15 years ago. USB 2.0 could manage it fineish. Maybe not at high resolutions and refresh rates, but it could handle a monitor just fine.
Yes, each number can land somewhere between 0-255, but there are some default reservations on specific IP ranges.
For instance, 0 is typically used as an identifier for the subnet, not as an actual device IP. For instance, a DHCP server may tell a device “your IP address is 192.168.1.168. The subnet range is 192.168.1.0/24 (meaning the mask is 255.255.255.0). But the 0 won’t (or shouldn’t) get assigned to a specific device.
255 is another special address, as it is used for broadcast messages. A packet sent to 255 gets sent to everything in that subnet. So for instance, if I wanted to broadcast a message to everything on the 192.168.1.0/24 range, I would send it to 192.168.1.255.
In regards to reserved IP ranges, there are a few standard private IP ranges:
192.168.0.0/16 one of the more common. (Subnet mask of 255.255.0.0). This basically means that (if everything is configured properly) your WAN IP won’t ever be something inside of that same range, as the router would very quickly throw up its hands in defeat. Like if your WAN IP from your ISP was 192.168.1.50, and you also had a device on your network with that same IP address, the router wouldn’t know which one (WAN IP or LAN device) to send traffic to.
The second private IP range is 172.16.0.0/20 (subnet mask of 255.240.0.0) meaning the second number can range from 0-31, and the last two octets can range from 0-255.
The last common private IP range is 10.0.0.0/8, (subnet mask of 255.0.0.0) so the last three octets can range from 0-255. You tend to see these more in corporate settings, as it allows for a truly astronomical number of devices to be connected.
Basically, all of this means that if you see an address in the 192.168.x.x, 172.0-32.x.x, or 10.x.x.x range, you know it’s a private IP address, not a WAN IP.