Asklemmy

44151 readers

2706 users here now

A loosely moderated place to ask open-ended questions

Search asklemmy 🔍

If your post meets the following criteria, it's welcome here!

Open-ended question
Not offensive: at this point, we do not have the bandwidth to moderate overtly political discussions. Assume best intent and be excellent to each other.
Not regarding using or support for Lemmy: context, see the list of support communities and tools for finding communities below
Not ad nauseam inducing: please make sure it is a question that would be new to most members
An actual topic of discussion

Looking for support?

Looking for a community?

Lemmyverse: community search
sub.rehab: maps old subreddits to fediverse options, marks official as such
[email protected]: a community for finding communities

~Icon~ ~by~ ~@Double_[email protected]~

founded 5 years ago

MODERATORS

[email protected]

222

Can someone demystify computer Ports for me? Please? Blocking, unblocking, opening, allowing, VPNs and their effect, what ports are and what they do, step by step, when you have to interact with them? (lemmy.dbzer0.com)

submitted 8 months ago by [email protected] to c/[email protected]

60 comments fedilink hide all child comments

It's the one thing when I'm configuring things that makes me wince because I know it will give me the business, and I know it shouldn't, but it does, every time. I have no real idea what I'm doing, what it is, how it works, so of course I'm blindly following instructions like a monkey at a typewriter.

Please guide me into enlightenment.

you are viewing a single comment's thread
view the rest of the comments

[–] Tylerdurdon 1 points 8 months ago

You have servers that provide some kind of resource or service, and clients that use those resources or services (will just say resource from now on).

Servers provide that resource using a port so clients will come ask for it using that port.

Sometimes servers can do multiple things, so they will provide multiple resources...maybe a web server hosting a web page is also an email server that can receive and send email too. They do those things using different ports to distinguish the kind of request it's getting.

On the client side, clients use source ports to distinguish which app asked for a resource. Think of your browser having 20 tabs open, each has it's own source port so your computer never gets confused which page goes to which tab.

I'm skipping a lot of things (ports flipping for replies, well known, etc), but that's the basics.