2.1 Compare and contrast Transmission Control Protocol (TCP) and User Datagram Protocol (UDP) ports, protocols, and their purposes

Port

Different path or road that data can travel down to get to different places.

TCP (Transmission Control Protocol)

Secure, reliable connection

Makes sure that the data gets to where it needs to be

UDP (User Datagram Protocol)

Connectionless.

Not guaranteed that the data is going to make it.

Connectionless Protocols

"I start talking. I don't even check if Bob's on the other end"

Ex. DHCP and TFTP

Connection-oriented protocols

Verifying that the other person is on the other end. Asking if they're getting the message. If not, then you'll resend the message. Finally, "Ok. Talk to you later. BYE."

Ex. HTTPS and SSH

TCP VS UDP

TCP: Puts the puzzle together to verify that all the pieces are there. Then, packs it up neatly and sends. If anything is missing, I will send you a new one.

UDP: Chucks puzzle pieces at you. I don't care if you get them all or if any are missing.

Why would someone want to use UDP over TCP?

Since UDP isn't checking to make sure that everything is okay like TCP, it's faster. You want UDP when the speed of communication is more important than reliability.

Ex. voice and video

FTP (File Transfer Protocol)

Port 20/21
Upload and download files

Secure Shell (SSH)

Port 22.

Secure Remote access to another computer over the command line.

Telnet

Port 23.

Unsecure remote connection to a computer over the command line

RDP vs Telnet and SSH

RDP: I see what's on your computer screen

Telnet and SSH: Command line

SMTP (Simple Mail Transfer Protocol)

Port 25
Send email

DNS (Domain Name System)

Port 53

Assigns IP address to Domain names

DHCP (Dynamic Host Configuration Protocol)

Port 67/68

Assigns IP addresses to computers

HTTP (Hypertext Transfer Protocol)

Port 80

Unsecure websites

POP3 (Post Office Protocol version 3)

Port 110

Receives email

NetBIOS (Network Basic Input/Output System)

Port 137/139

Legacy. Allows communication between computers and devices within a network

IMAP (Internet Message Access Protocol)

Port 143

Receives email

SNMP (Simple Network Management Protocol)

Port 161/162

Managing network devices in one (centralized) place

LDAP (Lightweight Directory Access Protocol)

Port 389

Get user info from directory

HTTPS (Hypertext Transfer Protocol Secure)

Port 443

Secure websites

SMB (Server Message Block)

Port 445

File and printer sharing on a network.

RDP (Remote Desktop Protocol)

Port 3389

In Windows

Secure remote access to computer via "screensharing"

TFTP (Trivial File Transfer Protocol)

Used by network devices to obtain a configuration file