How do you all remember common port numbers?

Do you just walk around muttering them to yourself for a day or so?

Maybe there are some little rhymes or somethings cos memorizing them is driving me nuts!

Thanks in advance,

Nver

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Comments

jovan88

You just pick it up eventually, like phone numbers and passwords it just sticks to you the more you use them.

ColbyG

It just happens after awhile.

Nvermind

bah! had a feeling you would all say that!

Thanks for your answers

pogue

I actually visually remember the two pages in my ICND1 study guide with the port numbers.

Also, to memorize, start by reciting the first 2 or 3 port numbers in your head, along with what function they provide (FTP, FTP Control..)

Then, add the next on the list, and keep repeating the whole list you've memorized. Keep repeating this step, and you'll be able to recite the whole list in your head.

The port number and function should come easily if you bear down and concentrate while memorizing. If you have a hard time memorizing whether they are UDP/TCP, just remember, the first part of the list is TCP. That way, all you have to do is remember that it is at DNS that you transition to both UDP/TCP.

Use little "tricks" to remember whether the functions in the middle of the list are UDP or TCP.

"Trivial" File Transport Protocol is "trivial", so it does not need reliability, so it is UDP. Also, it is the "sexy" protocol used to load stuff on a router. "Sexy" = port "69".

Depending on how you personally memorize best, you have to develop little "tricks" like this to help yourself.

Here's another example. Let's take the first three well known port numbers that Cisco wants us to memorize:

20 FTP
21 FTP Control
22 SSH

They are all TCP. To remember them as a unit together, think of some memorable words.

FiT
FiT
faSHisT

The way I memorize, these words are easy to memorize. I now know the first two ports begin with F, and since they end with a T, I know they are TCP. I know the third port number has an SH in the name, and with these words, all I have to do is remember the numbers 20-22 and associate them with this three words block.

Now, instead of associating each port number individually with it's function and whether it is TCP or UDP, I can just remember

FiT FiT faSHisT, 20-22

And this is enough for me to know the first three port numbers. Build similar type words blocks for the other port numbers, and it becomes a lot easier to remember.

This is the same concept as remembering the phrase:

All People Some Times Need Data Processing

in order to remember the order of the levels of the OSI model.

Change hard to remember concepts into easy to remember words.

Hope this helps.

Russ

networker050184

Like others stated they start to stick after a while. For the ones that don't I keep this bookmarked

Pash

I am kinda fortunate in that I often make changes to big 6509 switches with a monster amount of acl's on them, when you know the "human word" or port number for a lot of rules then it kind of sticks for everything else.

As others have said, with time it will stick like glue.

Cal_0808

Try recording yourself reading them all and then putting them on an mp3 player or your phone or something and listening to them once in a while, that worked for me.

A friend of mine gave the hint to put them all on seperate post it notes and post them somewhere you look at everyday, bathroom mirror somewhere like that

blackninja

Not too hard to remember them after while, it sort of just happens. Stressing about it is prob the worse thing you can do.

If you have a lab or PT, setup some ACLs with the diffferent port numbers. Or when see or read about a certain protocol say the port number. e.g. When you receive an email say - tcp port 110. When you send an email say - TCP port 25, T.F.T.P. - UDP and we we all love this one

Before you'll realise you'll know all the common ones.

tiersten

You just know them after a while... At least for the more well known ports anyway. I wanted to know the port number for something obscure then I'd look it up

rakem

Google remembers them for me!

Forsaken_GA

You get used to the port numbers after awhile just from working with them. For everything else that's common, I can **** and use /etc/services on debian installs to check wtf the protocol is. For anything that's esoteric, google is my bestest buddy

dwcoffin

I came up with a mnemonic for memorizing common TCP protocol ports.

"For Some Techs Simple Deeds Have Put Nice Networks In Harm"

Protocol Port Phrase
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

I remember the first ports start with 21, 22, 23.
Last two digits of previous 2 ports equals 5 so next is 25;
the reverse of 25 is 52 so next port is 53;
I always knew HTTP is 80 and POP3 is 110.
NNTP with 2 N's makes me think of NiNe so its 119.
I know NTP is 123
IMAP4 has a 4 which leads me to 143,
Put in another 4 for HTTPS so its 443.

Maybe I have Aspergers or something but I was pleased to come up with the mnemonic phrasing and seeing the numbers in the numeric order helped me come up with mental triggers laid out above for remembering the port #s. Ask what they are individually and I am hard pressed to tell you without doing my exercise.

Just my 2¢ and if it helps great.

Good Luck

Cisco Inferno

i always make a chart on paper and pin it above my desk on the wall.

NetworkVeteran

Nvermind wrote: »

Do you just walk around muttering them to yourself for a day or so?

The ones I know I've simply used so many times. The ones I don't I just Google if I need them.

pamccabe

Some good ideas here, glad I looked at this thread. There are a couple I get mixed up on so I am still memorizing these before my exam. One thing that has really helped me is flash cards. There is a program called Anki that lets you create your own flash cards. You can export the cards you create to a smartphone also for those on the go. I love the program and it really helps me memorize concepts. I use them whenever I have time.

dazl1212

For the N+ at least i just continously did the quiz on here for about a week

kurosaki00

I dont... lol
I only know like 6 because I work often with them or used to work often.
I also know some other random ones because of work, like IPsec-ESP port 50
because I did some configuration in my old job in the firewall

You will learn some for your cert exams, but the rest you will pick up as you work with em

nickelito

I did this when learning for the ccent.. now ive forgot them, but like someone said. the more you use them the harder they'll stick:

22H (SSH) = 22
T3LN3T = 23
5MTP (SMTP) = 25

..just to name a few.

d6bmg

Just by memorizing it. And after working some time with them, you just can't forget them.

SteveO86

As time goes on and you work with more an more protocols they will just stick.

I started out remembering the ones from the CCNA/Network+ material, as I got deeper in the world of networking and worked with ACLs and FWs that knowledge quickly.

You will also slowly pick on port numbers when you start troubleshooting using tools like NetFlow and TCPDump/WireShark

Jasiono

IMAP - ILoveYou - 143 lol

GoodBishop

To use a line from Fairly Oddparents... "Internet!"

powmia

I use linux, it has a file /etc/services that contains all of the port numbers... so if I want to find out which port is imap:

me@null:~$ cat /etc/services | grep imap
imap2 143/tcp imap # Interim Mail Access P 2 and 4
imap2 143/udp imap
imap3 220/tcp # Interactive Mail Access
imap3 220/udp # Protocol v3
imaps 993/tcp # IMAP over SSL
imaps 993/udp

Cisco also keeps a list for NBAR that is viewable on routers:

null#sh ip port-map | include imap
Default mapping: imap tcp port 143 system defined
Default mapping: imap3 tcp port 220 system defined
Default mapping: imaps tcp port 993 system defined

You get used to the numbers eventually, in the mean time... aside from pop quizes, you don't need to memorize. You just need to know how to get the answer quickly.

Master Of Puppets

Experience!

Minary

I really like Mnemonics. I know most of the ports but there are some I don't use enough yet to
remember.

I have borrowed from above and added a word: For "Food" Some Techs Simple Deeds have put Nice Networks In Harm

20

21

22

23

25

53
80

110

123

123

143

443

FTP

FTP
Control

SSH

Telnet

SMTP

DNS

HTTP

POP3

NNTP

NTP

IMAP4

HHTPS

For

Food

Some

Techs

Simple

Deeds

Have

Put

Nice

Networks

In

Harm

It starts at 20 , 21, 22, 23
25 = 2+3 from 23
53 is the reverse of 52 "+ 1"
80 = 5 + 3
110 = I justt know it
119 = has 2 N "Nines"
123 = Rythms with NTP
143 = has a 4 in it
443 = put in anther 4

I created a way to remember the Cisco Notifications using a story which I will put in a seperate post.

ande0255

I made a ton of flash cards for random commands, port numbers, IPV6 addresses, etc. That's the only way I can memorize something is by answering it in question format over and over again.

RAMBUS

Wanted to say thanks to you for posting your thread on ports, your mnemonic worked great. I studied last night on ports and used your suggestion. i sat down and wrote this down on the pad provided at the center before i started the test. boom,worked like a charm.

MJohnsonres

I like to use Quizlet and Encore (Web and App versions).

Someone probably already created a set of flash cards for Network Ports.

1st Create some flash cards ( Port Number on one side, Description on the other)

2nd Create another set of flash cards (Port Number and Short Description on one side, and Detailed Description on the other side).

* or good ole paper flash cards, print the list and tape them to the cards and have at it.

Devote 30 minutes in the morning, afternoon and evening.

Also if you make groups it will make it easier to remember groups of ports.
i.e. Trival Gophers, Finger, Apples (69, 70, 79, 201)

You can also try: https://memorize.com/network-port-number/benzart

Hope this helps

beads

You will once you start using them a few times. Working inside a firewall configs and initial setup work wonders!

- b/eads

Mike7

Spend time configuring a firewall, analyzing IPS logs and troubleshooting app network connecting issues.
Run netstat -anb to view listening services on your PC/server, and to configure host firewall to allow a certain service.
You will soon remember ports used by common apps and services, P2P software, remote admin software and even malware.

There was one exam I took where you are required to configure firewall to allow a certain service through. The knowledge helps.