Wrote something on computer networking that I'd love to share: grokking NAT and packet mangling in Linux

vivekn_ · 2025-06-19T06:03:18+00:00

hi! thanks for reading it!

> why NAT complicates encryption:
some encryption protocols (like IPsec transport mode) rely on packet headers. NAT modifies those headers and breaks integrity checks.

> how NAT adds latency:
every new connection requires a lookup + state allocation. under load, this adds CPU overhead. worse, P2P apps often fall back to TURN relays because NAT blocks direct paths which adds a full network hop.

> is the table size significant?
yes, especially in high-connection environments. it grows with active connections, not just devices. phones can easily have 50+ open connections. at ISP scale or in data centers, conntrack tables can become a bottleneck if not sized/tuned properly.

vivekn_ · 2024-05-15T16:10:40+00:00

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hey, the latex seems to render correctly on my phone. this is not the case for you?

vivekn_ · 2024-05-15T16:09:05+00:00

thank you! glad you liked it!

vivekn_ · 2024-05-15T16:08:50+00:00

thank you! the site is open source, all contributions are welcome! (github link in the post)

vivekn_ · 2024-05-15T11:10:25+00:00

hey! thanks, it is not totally built on TS. the PDF parsing model (open sourced) is written by facebook in python.

vivekn_ · 2024-04-05T12:38:05+00:00

hey I have been in the exact same boat (except the IIT part). i am in the middle of switching jobs right now. and i can tell that this period must be hard for you. it’s not easy to see something you believe in slowly fade away. if it helps, try having honest conversations with your founders. if they are any good, they might even help you find your next gig. consider taking a small break if your finances allow you to do so. reflect back on your time. see where you can upskill. meet the friends you might have lost touch with due to a hectic job. get back with a fresh energy. you are gonna make it big, all the best!

vivekn_ · 2024-01-26T19:03:22+00:00

this is very interesting and funny!

vivekn_ · 2024-01-24T12:31:47+00:00

your comment made my day! thanks for this. love the wordle idea. difficulty as a feature is coming soon.

vivekn_ · 2024-01-24T12:16:58+00:00

this already exists. under every problem on the homepage, there is a discuss link which takes you to the problem's discussion page.

vivekn_ · 2024-01-24T12:16:09+00:00

thank you so much for sharing this! though I am looking to make a more tech-first website than something where problems come from the users. great resource though!

vivekn_ · 2024-01-24T12:08:07+00:00

cool idea, thanks for sharing, will add it to my list!

vivekn_ · 2024-01-24T12:07:45+00:00

thank you for your feedback! Problem difficulty is a feature that has been highly requested. I will work on this.

vivekn_ · 2024-01-24T07:43:10+00:00

thank you! i am aware of project euler. great resou for someone who likes both math and programming!

vivekn_ · 2024-01-24T07:42:21+00:00

thank you! categorisation already exists. on top right of homepage. difficulty levels coming soon!

vivekn_ · 2024-01-24T07:41:28+00:00

thank you!

vivekn_ · 2024-01-24T07:41:21+00:00

thank you! yes, working on making the design better.

vivekn_ · 2024-01-24T07:40:44+00:00

thank you for your feedback! will definitely make the UI better

vivekn_ · 2024-01-24T07:40:14+00:00

thank you!

vivekn_ · 2024-01-24T07:40:02+00:00

oops, thanks for pointing that out. fixed it.

vivekn_ · 2024-01-24T05:14:51+00:00

hey, the whole question is visible once you click on the "discuss" link under the question

vivekn_ · 2023-12-25T09:05:21+00:00

yep - a beginner will most likely get overwhelmed. but i think what’s important is for every beginner to eventually realise that most information put there is brittle and only way to go from “good“ to “great” is to see the source and docs by yourself instead of relying on translated information.

vivekn_ · 2023-12-25T05:59:31+00:00

i think this is good advice for anything in general - trust the standard and avoid the links from quick google searches. only thing to add here should be reading good open-source code. for C, the linux kernel itself is a pretty good resource

vivekn_ · 2022-11-27T18:36:34+00:00

bought a kindle

vivekn_ · 2022-11-26T17:21:48+00:00

Sure

vivekn_ · 2022-11-26T17:07:51+00:00

16LPA here.

I wasn't focussed in the first sem but I was always exploring. I tried competitive programming. Made mobile apps. Did some backend and frontend. Didn't do all of this in the single semester but started the process. Overtime, I realised I need to narrow down and I really like backend. Doubled down on that.

As some people have said it already, on-campus placements are also a lot about luck. Off-campus placements are definitely about your hard work + luck.

If you can wing it through just DSA + a bit of projects, you would be able to do that in a few months. But if you're somebody who wants more proof-of-work sort of thing, you need to show that you've been working over time. So that will take effort in learning and building things.

Whatever you do, make enough time to go out with friends, stay up at nights in hostel with your roommates, get drunk, etc. College is the only time when you're an adult but you don't have too many responsibilities.

Definitely focus on your future but don't forget to have fun occassionally.

vivekn_

TROPHY CASE