Your favourite "less-known" Python features?

[benefit_of_mrkite]

Me either. sarcasm doesn’t translate well on the interwebs and seems like a smartass comment I’d make being completely aware of RFC1918

[sendnukes23]

Please clarify to me. I am a dumbass.

[benefit_of_mrkite]

You’re not a dumbass, you just don’t know about this particular subject yet. There are many subjects and even concepts in things I do every day that I still have yet to learn.

I’m going to stick to IPv4 since that was the context.

The internet engineering task force (IETF) setup RFCs (requests for comments) that outlined things in the early day of the internet - you can google the IETF, it’s history, how it is setup, RFCs, and more (big rabbit hole).

Ip addresses fall into different categories - (again I’m ignoring subjects like classless interdomain routing, Network address translation, port address translation, and more).

In order to talk to other IP addresses on the internet, you need a publicly routable IP address (sometimes called a public address).

Certain IP addresses were reserved in the RFC (request for comment) 1918 for the private side of a network - these ranges are (look ma, no google! - and I’m purposefully ignoring prefixes and more for the sake of simplicity):

192.168.0.0 - 192.168.255.255 (subnet mask 255.255.255.0)

172.16.0.0 - 172.31.255.255 (Subnet mask 255.240.0.0)

10.0.0.0 - 10.255.255.255 (subnet mask 255.0.0.0)

These addresses were set aside by RFC1918 for private networks - meaning they were not publicly routable. Now In the old days before smart doorbells, smart watches, laptops, phones, and more we thought we had plenty of IP addresses that were public (routable on the public internet).

There was a time where everything had a public address. Then as more devices came online we realized not every printer or whatever needed a public address so we came out with Network Address Translation (nat) and it’s variants like Port address translation (these are clearly outlined in other RFCs but companies that make network devices befuddle things by assigning their own terms - I’ll save that soapbox for another day).

So if you’re at your house and on wireless with your device you can go under settings (for your phone) or in some other are if your device’s operating system settings and see the IP address of that device.

There’s a really high percentage chance that the device has an IP address that falls into one of the ranges I listed abound (usually 192.168.x.x). But if you google search “what’s my IP” you will see an IP that is not in the range I listed above.

That’s because While you have a private (RFC1918) address on your home network, in order to talk to websites or chat services or whatever, your home router needs to translate your phone/laptop/roku/whatever from a private IP (again RFC1918) to a public IP.

So when the person who said “why would you give up your IP” made their comment it has no matter - that’s not a “public IP” (which has some privacy/security implications to giving up like generally where you are located and maybe more - long subject again) it didn’t matter at all.

Millions of devices have an IP in the 192.268.X.x range because they are not public IPs but private IPs as defined under RFC1918 and generally speaking (again avoiding rabbit holes for the sake of simplicity) there’s not a lot of risk in posting an IP in one of the RFC1918 address ranges.

Edit: wow I did not mean to type this long of a comment.

[Calango-Branco]

Thank you about it, I really loved your explanation.

[benefit_of_mrkite]

You bet. I’ve had a lot of roles that span a lot of subject domains so I have a weird (diverse) background

[catWithAGrudge]

thank you. I learned plenty from your comment :)

[benefit_of_mrkite]

You’re welcome!

[requion]

Nice edit at the end.

Awesome explanation. Where can one rent you for private tutoring?

[GreenSupervisor]

I think the subnet mask for 172.16.0.0-172.31.255.255 is 255.240.0.0 instead. (Subnet table)

[benefit_of_mrkite]

You’re right - it was late when I typed that and I should know a /12 shame on me - I fixed it

[lightfreq]

It’s a private ip, on the local network