First port your computer hits

[@hnasr]

Get my Fundamentals of Networking for Effective Backends udemy course Head to network.husseinnasser.com (link redirects to udemy with coupon)

[@richardkoplinger4808]

Thanks!

[@panththakkar7868]

Awesome content. Hussein could you make a video on some of the books which you would recommend related to software engineering. It would be really helpful.

[@Tushar130496]

I didn't considered DNS query lookup and answered 443😅 Learned many new things. Great video. While writing this comment was about to ask DoH but it was answered. 😅

[@fedelecavaliere5249]

Somehow with each one of your videos there is something new you learn. What the heck is DoH?! Nice. You are a pure inspiration.

[@apidas]

I love this. people are going to assert their seniority by explaining such useless trivial questions. not that I against knowing it. just asserting it

[@thiagovfar]

Pedantic call out: UDP is _connectionless_ . First _connection_ would be one of the TCPs.

[@jjarechiga]

🍻

[@sanilkhurana3991]

Hey Hussein nasser, loved this interactive style content! Hoping for more of these. I liked that the question was open-ended and really makes you think. Another great addition could be a sort of simple QnA on the LInkedin post to clarify details. This question had a lot of interesting points, for example, I didn't think of considering DoH. So if people could ask these assumptions(for example, someone could ask whether you are using DoH?) in the linkedin post and you could answer them, that'd be great as well.

[@hnasr]

Head to database.husseinnasser.com for a discount coupon to my Introduction to Database Engineering course. Link redirects to udemy with coupon applied.

[@rahulchotaliya256]

Awesome video, love learning things with minute details!

[@nebsun]

Generally DNS goes ove UDP, which I don't consider a 'connection', also using plugins like httpseverywhere prevent the connection to port 80 from going through and internally redirect to 443

[@rne1223]

You got me...didn't think of dns.

[@arihantverma6955]

Great video Hussein!

[@addiegupta]

10:43 big brain time

[@sachinchauhan6489]

You use the word "effectively" very effectively.

[@anirbandutta1371]

It will go through many other random outgoing ports on lower level networking layers. But yes, 443 is most appreciate considering we have DNS cache or DNS over https

[@NeonNotch]

If it’s the first visit, you won’t have DNS cache.

[@jimrox-i5v]

By many other random low level ports, you're referring to protocols like DHCP, ARP which might be needed, if the computer is connected to a new network for the first time, innit??

[@deletevil]

Sir, please make a video on this. I didn't know about this until today I read something on Quora. Basically whatever (most of us, not necessarily you) we know about OSI is almost *Completely* outdated. This is taken from Dr. Toni Li, an elite level computer scientists. I think I've read somewhere about him that he was one of the members of the very first Internet construction crew. Following is a copy-paste of his answer to a question "How do you explain the concept of the OSI model using practical examples at each layer?" : "OSI layering doesn’t work. We don’t use it. Therefore, the practical example is a pile of trash in the bin. Then you introduce the correct, TCP/IP model. Layer 1 (Physical layer): Twisted pair, Wi-Fi in 2.4Ghz or 5Ghz Layer 2 (Link layer): Ethernet, 802.11a/b/… Layer 2.5 (Forwarding plane): MPLS Layer 3 (Network): IPv4, IPv6 Layer 3+ (Routing protocols): BGP, OSPF, IS-IS Layer 3.5 (Tunnel): GRE, LISP, IPsec Layer 4 (Transport): UDP, TCP, QUIC Layer 5 (Application): FTP, HTTP(s), SMTP, IMAP, POP, … Please note that even this model no longer works. Layered models are obsolete. Networking stacks are more general architectures and need more functional flexibility than is expressed by simple layers." quora.com/How-do-you-explain-the-concept-of-the-OSI-model-using-practical-examples-at-each-layer

[@supernovaw39]

Strict-Transport-Security is only valid as long as you're already connected over TLS. In cleartext HTTP, HSTS is ignored.

[@ward7576]

What's your name? - "Well, in one configuration it can be Hussain... but then I am going to contradict myself, since in other configuration it might be Hussein... and not even then the answer would always be correct".

[@therandomguyinworld]

have a good day sir plz can you share any content about monitoring the application and Site reliability

[@ramymousa4189]

love your content!

[@vigneshwaran1516]

That's why AWS named their service route53, I guess

[@sarathkumarm7221]

Hello sir, Please explain about nodejs memory leak and how it fix. What's a best way to develop a socket with nodejs applications. Please🙏

[@driziiD]

memory "leaks" when the garbage collector is never able to clear an object in memory...this usually happens when you have objects that cyclicly depend-on/refer-to each other. I've seen languages like obj-c let progranmers prevent memory leaks by letting programmers declare certain pointers as "weak" pointers

[@NeonNotch]

I get that UDP is “connectionless” but at the same time I don’t. Any enterprise firewall nowadays will have an embryonic connection limit for everything but ICMP (?). Also, being pedantic and saying udp/53 isn’t a connection is weird because then HTTP/3 becomes “connectionless” as well, correct? Overall, being iffy on the choice of “connectionless” is dumb in this scenario as it’s easily understandable what he was getting at. I’d say 53 is the first “connection”.

[@NeonNotch]

Nvm, I was wrong and HTTP/3 is indeed connectionless as well. TIL.

[@dragon_warrior_]

DoH was something new!

[@adedotunadedigba466]

Hi Hussein, could you please make a video on how the Shazam app was engineered?

[@samuelhulme8347]

Jeff Geerling: It was DNS

[@sadBytes]

hey, looks like you have mistyped the python link to your udemy course.

[@michaelhill7774]

Do you like your Secret Lab chair?

[@kgermando]

80

[@comradepeter87]

What about DNS over HTTPS? My Firefox is configured to use that so technically I'm still right 😅 EDIT: Should've waited before commenting 🤦

[@AkshayKumar-kz6zh]

First time? XD

[@sapito169]

wtf port 53 amazing

[@jjarechiga]

67

[@jjarechiga]

Can't DNS without an IP, most people get it via dhcp

[@tirthu1]

404

[@RyanBess]

Its not your browser thats reaching out on udp 53. That is your dns client.

[@_framedlife]

Most popular modern browser handle DNS themselves unless you ask it not to.

[@DeepakGoyal]

Could you please clean your mic?

[@manjunatha5a]

And talk about that moustache, pls.

[@hexadefender]

its 443 for https lmao

[@susmitislam1910]

"For the first time". Port 53 for a DNS lookup.