71 points

This is a really good way of explaining the difference.

permalink
report
reply
92 points
*

Nah, tcp still yeats the baby, it just verifies that it was caught unbruised, or at all. If it wasn’t that’s ok. Try again. Yeet the baby’s little sister

permalink
report
parent
reply
10 points

You got that baby? Great, I’ll send the next 500 much faster, tell me when you drop one and I’ll slow down again.

permalink
report
parent
reply
13 points

So, UDP just sends it out there and anyone can intercept it?

permalink
report
parent
reply
44 points

No. Both UDP and TCP can be intercepted the same. The difference is that UDP sends a packet to an address. But doesn’t have any in built system to check that it arrived, that it arrived intact or to resend if it didn’t. There’s also no built in way to protect against spoofing or out of order packet delivery. But generally implementations will handle the ones that are important of those themselves.

TCP establishes a circuit, packets are sent, verified and resent if required until the original data, in the correct order is delivered to the application. Also there is some protection against spoofing with sequence numbering. The downside is that time sensitive data might be delayed because of the retransmission and re-assembling. Which is why time sensitive streams like VoIP are usually sent over UDP.

permalink
report
parent
reply
13 points

Btw, on my device you sent the message -110min ago, not 110, -110

Welcome, traveler from the future

permalink
report
parent
reply
27 points

No. UDP is at the packet level. Interception is a different layer.

To use to today’s language, UDP yeets the packets at you as fast as it can generate them.

It doesn’t care if you catch any of them.

Don’t yeet the baby.

permalink
report
parent
reply
40 points

actually, do yeet the baby if you have an application with different needs. for example, if you want to play a game, you’re better off yeeting 60 babies a second and just hope that whoever is on the side catches enough of them to get a smooth stream of babies, than making sure every baby is handed gently to the next person and get the whole line clogged up the moment anything disrupts it. if you just use the yeetomatic 3000 you’re always getting fresh babies on the other end, a few might just be dropped in the process

permalink
report
parent
reply
7 points

Don’t yeet the baby.

or at least care if you catch any of them.

permalink
report
parent
reply
3 points
*

What do you mean interception is at a different layer? You can capture at any layer as long as the payload isn’t encrypted, and if it is, you still get layers 1 through 4 (Physical, Link, Network, and Transport).

permalink
report
parent
reply
1 point

Is it like multicast or are they the same?

permalink
report
parent
reply
7 points

It’s not so much that anyone can intercept it, it’s more that the sender just blasts it and no acknowledgement so there’s lots of potential for loss

permalink
report
parent
reply
4 points

The benefit is that you don’t need to wait for verification from the user that they got the packet before you can send the next group of packets. If you’re, say, watching a stream, it’s not important that you received the packets because that’s just a few skipped frames or a second of lag, whereas the tradeoff on overhead is pretty big.

TCP is more important with like file downloads where it’s okay if it takes a couple hours to get a really big file as long as that file isn’t corrupted or missing any data.

permalink
report
parent
reply
3 points

You’d have to be somewhere in the route from A to B to intercept it. But TCP is no different in that regard.

TCP is connection based so both sides need to agree to connect before data is exchanged. UDP is connectionless, so it will send data from A to B (and vice versa) regardless of if the other side is available.

permalink
report
parent
reply
2 points
*

From what I can tell yes. There’s no established connection, the data is sort of just broadcasted.

Edit: I was operating under a misunderstanding, please refer to andrew’s response.

permalink
report
parent
reply
8 points

Broadcast would mean it’s sent to anyone. UDP packets still usually have a unicast address and thus are routed by routers and switches to specific machines, but as a connectionless protocol, UDP never validates which, if any, packets are received by the recipient like TCP does. If any verification is needed that needs to be handled higher in the OSI stack. E.g. by the application layer.

permalink
report
parent
reply
5 points

No no, it’s not “broadcasted”. It still has a fixed sender and receiver IP address, but UDP doesn’t verify whether the receiver got the data or not. You can implement that over UDP, but you have to do it yourself.

With TCP, the packet will retransmitted automatically if the receiver didn’t tell the sender “yep, I got it”.

permalink
report
parent
reply
1 point

No, instead of using TLS for encryption (like most TCP traffic) UDP will use things like DTLS and SIP

Or if you’re asking about the actual transport it’s more like TCP is going to your friend’s house and calling your mom to let her know you’re there vs UDP is going to their house and not calling.

permalink
report
parent
reply
41 points

Wanna hear a UDP joke?

Nevermind, you wouldn’t get it.

permalink
report
reply
21 points

“You might not get it”

permalink
report
parent
reply
5 points

“not get You” Don’t forget the packet loss and non-ordered packets.

permalink
report
parent
reply
29 points

Alice and Bob are friends at ${university_name}. At ${date_time} they cross paths.

Alice: Hi, I want to tell you a TCP joke.

Bob: Sure, I’m ready to hear the TCP joke.

Alice: Alright,I am going to tell you the TCP joke.

Alice: Here’s the actual joke. It’s hilarious.

Bob: laughs hysterically

Alice: I’m glad you liked my joke.

Alice: Alright, that was the TCP joke.

Bob: Thanks for telling me about it.

Bob: So, that’s it I guess?

Alice: Yeah, that’s about all I wanted to tell you.

Alice and Bob part ways and run off to their next classes.

permalink
report
reply
22 points

Old but gold.

permalink
report
reply
9 points

Hey, that’s racist!

permalink
report
reply

Programmer Humor

!programmerhumor@lemmy.ml

Create post

Post funny things about programming here! (Or just rant about your favourite programming language.)

Rules:

  • Posts must be relevant to programming, programmers, or computer science.
  • No NSFW content.
  • Jokes must be in good taste. No hate speech, bigotry, etc.

Community stats

  • 5.1K

    Monthly active users

  • 1.5K

    Posts

  • 33K

    Comments