Suggestions to learn well known ports?

I am having a terrible time with port numbers in Network+. Except for 20-23 80 and 443 I'm pretty much guessing on practice tests. I tested on flash card sites and have made my own flash cards but neither helped much. Any suggestions on learning these?

I prefer mnemonics and have become quite good at practice tests on the OSI Model because of Sausage Pizza, BFPS, and HSR.

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Comments

JasminLandry

I actually studied the services file in Windows (C:\Windows\System32\drivers\etc\services). And also seeing those ports in action using Wireshark.

Ruminus

JasminLandry wrote: »

I actually studied the services file in Windows (C:\Windows\System32\drivers\etc\services). And also seeing those ports in action using Wireshark.

^This. If you're not in a job already where you deal with ports on a daily basis, watching the ports as they work can be the easiest way to remember what does what. I tried memorization of tables, but it didn't really stick. When I started really watching what was going on across the network at my job, things started to make sense.

techfiend

I will give these suggestions a try, thanks.

Chev Chellios

Have you checked out Professor messer or anything else like that as well? He has some useful stuff in his videos

TechGuru80

Repetition is how I did it. See protocol, say port...see port, say protocol.

lsud00d

I tried to focus on pairing the service with it's secure counterpart, i.e.

HTTP/HTTPS: 80/443
LDAP/LDAPS: 389/636
SMTP/SMTP(SSL/TLS): 25/465
IMAP/IMAP(SSL): 143/993
POP/POP(SSL): 110/995
FTP/SFTP: 21/22

This takes care of most of the major services, then just fill in DNS, SSH, DHCP, etc.

techfiend

Services file is an overload of information at this time for me. Wireshark would be helpful but I don't use SNMP, Telnet and rarely use DHCP, FTP, LDAP, IMAP, POP3, SMTP, SSH and many others. The only commonly used ones are HTTP(S) and DNS.

I guess going back to repetition is the only way for me at the moment. I spent the 30 minutes before my A+ 801 and 802 tests on port flash cards. I maybe was getting about 50% correct, and wrote what I knew on the white board asap. Turns out I didn't see 1 port question on either test. Is there port questions on the Net+?

BlueRoze

CompTIA lists 10 ports in their, "required knowledge," document on their website. I tell my students to focus on these and they'll probably get most of their port questions right. As soon as you sit down to test write the port numbers you remember on the scratch paper. They will be fresher in your head than when you are at question 65 and feel a little brain numbed. I think I had a couple of port questions when I took it but it wasn't an excessive amount.

Priston

Flash cards?
Cards: TCP and UDP Ports | Quizlet

PJ_Sneakers

Use the "practice exams" listed on this website. Do the port numbers quiz over and over. Do it on your lunch break, and before bed. Etc. Just do it until you have them all memorized.

fuz1on

Ports are just going to become second nature to you as you do more work but @lsud00d's pairing technique is pretty good! I use something like that but most of the time it's just straight memorization where you just don't need to think about it anymore. Also, I really learn things faster by writing it down on a piece of paper and/or repeating it to myself. Good luck and you'll get it soon - just watch, one day you'll wake up and be 'ports-for-brains'!

FTP
20 - Data: TCP/UDP
21 - Control: TCP

SSH/SFTP/SCP
22 - Secure: TCP/UDP

Telnet
23 - "Jordans": TCP/UDP

SMTP
25 - "Square" TCP

Trifalger

I was looking for help with this yesterday and have been practicing the mnemonic I found here at Techexams. It works pretty well to have as a platform for later memorization. It's quick and easy and you can always discard it and add onto it later.

Anyway, this is what dwcoffin posted and I can vouch for it:

FTP 21 For
SSH 22 Some
Telnet 23 Techs
SMTP 25 Simple
DNS 53 Deeds
HTTP 80 Have
POP3 110 Put
NNTP 119 Nice
NTP 123 Networks
IMAP4 143 In
HTTPS 443 Harm

http://www.techexams.net/forums/ccna-ccent/42866-how-do-you-all-remember-common-port-numbers.html

Codeman6669

Bro. Sit the heck down im about to blow your mind (not really but this is going to really help)

Whenever you have to memorize a numbered item such as ports, OSI layer, cable bandwidth speeds, etc. Write down the things you have to memorize from least to greatest just like this:

20
FTP -- Data

21
FTP -- Control

22
SSH Remote Login

23
Telnet

25
Simple Mail Transfer Protocol (SMTP)

Now take a index card/flash card and place it right under the very first one. So under 20, covering the other port numbers below it with the card.

Now try to guess the next one? 21! why? Because 21 comes after 20, and you KNOW its FTP because they are right after each other in numeric sequence.

Now move your index card under 21. Covering the other ports below.

Guess the next one... try hard. Move the card down one and look at the answer if your right, move on. If your wrong look at it and say in your head or out loud " SSH 22, SSH 22, SSH 22, 22 SSH, 22 SSH, 22 SSH". Now put the index card over all of them except 20. and start the process over.

If you forget one, don't keep going down the list. No, you need to get the order solid. Your using your mind to do something it already understands (numeric sequence), and then just applying some info next to it.

Do this until you can get the index card below all of the ports multiple times. Now do it from greatest to least. Then start mixing it up.
Cover the #s with the index card but not the port name, and see if you can guess what port number goes to the name, using the same method as above.

If you have a real hard time remembering one. BE Aggressive!
Open to a clean sheet of paper, now write the port name and port # while saying it out loud. Fill up a couple pages. Just keep writing it out, until it sticks. When you walk away from studying and go do something else, you will remember that, and every now and then say it in your head.

you do this you will have it.