Know your protocols — Protocols, Ports, and their magic use (In The Context of Cyber Sec.) | by Reza Asif | InterviewNoodle | Jul, 2022

“Maybe I can’t learn your server’s thoughts, however the Port numbers do the truth is communicate to me!”

Because I instructed you so. Joke. The factor about ports is, they’re often related to particular use circumstances. In reality, typically they’re reserved and should be picked for particular use case (service) to work.

Now if you happen to scan a system, and discover out port 80 is open and lively, then this machine is operating a web page which anybody may entry. Perfect, we may begin hacking there. Port 22 in use? Someone is accessing command line interface and does admin actions? Port 443? He is operating a protected web site. Must be essential. I scent some doable treasure. Port 2525? He is sending out mails. Maybe I can simply ship emails respectfully on behalf of him. You get the concept.

Sure factor, it’s not simple to maintain monitor of all these ports and you would look them up. Or possibly simply bookmark this web page and you bought an outline on your fingertips. Enjoy:

Setting the scene..

In the fashionable (cyber) world, to search out somebody or one thing, you often want an FQDN or an IP deal with to search out it. There is perhaps different methods, however that’s not related now.

Wait, there may be extra! Usually, if you wish to discuss to a service, you specify IP and a port quantity! (e.g. 127.123..::80; format: ::

Human readable instance

In the actual world, it’s in-fact much like having avenue title (IP) and home quantity (port) to search out the situation of a home.

Local host for example

IP 127.0.0.1 is the native host. Entering this in your browser, it would attempt to discuss to your personal pc as that is related as native host. Now what to search for? If you add ::80 to the IP, then your browser is aware of, that you’re in search of precisely this port — no matter service is perhaps provided. Usually HTTP is related to port 80. It is the protocol used to current a web page with none authentication required. If you’d arrange a service like web-service on this particular port, then the truth is the browser would open the web page situated on the pc.

(this listing will develop over time)
(use browsers search to search out the one you might be in search of)

(Here is a simplified overview: https://en.wikipedia.org/wiki/List_of_TCP_and_UDP_port_numbers)

Telnet, FTP, SMTP, HTTP, DNS, IMAP, POP3, PTP, SSH,

Telnet: Used to work together with distant computer systems. Port 23.

FTP: File switch protocol — used to switch files from a server to a consumer. Usually, port 20 or 21.

HTTP: Hypertext Transfer Protocol — used for or transmitting hypermedia paperwork, similar to HTML. It was designed for communication between internet browsers and internet server. Port 80

HTTPS: Same as HTTP, however with Security extension (TLS). Port 443

DNS: Domain Name System — hierarchical and decentralized naming system used to establish computer systems and title decision reachable by the Internet. Port 53

SMTP: Simple Mail Transfer Protocol — used to ship mails. Usually, Explicit SSL/TLS port 587/2525; Implicit SS/TLS port 465; SMTP Relay port 25;

IMAP: Internet Message Access Protocol, used to obtain mails — Port 143/993

POP3: Post workplace protocol — one-way client-server protocol through which e mail is acquired and held on the e-mail server. The consumer solely downloads a replica, however will not be the receiver. Port 110/995

SSH: Secure Shell Protocol — a cryptographic community protocol for distant login and command-line execution. Port 22

PTP: Precision Time Protocol (PTP) — used to sync clocks by a pc community. Port 319/320

UDP, TCP

Ethernet, Token Ring, PPP, FDDI/ATM IEEE 802.3/802.11

Thank you for flying over my weblog publish. If you might be questioning which of them you need to be taught and know by coronary heart — here’s a advice: Don’t power it. Keep your eyes open whereas reviewing technical particulars. The extra typically you see a port, the extra related it’s. Then strive keep in mind them. You’ll affiliate them with an expertise and thus keep in mind for lifetime. Cheers, peace OUT.

Source: Trust me on this one. I studied for the information and community safety examination as half of the M.S.c. Applied IT Security program at RUB