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sgirvin | CompTIA A+ | Module 2.4 - Common TCP and UDP

By: sgirvin | Related Course: CompTIA A+ | Published: December 20, 2017 | Modified: December 20, 2017
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NotepadCommunication Protocols: TCP

TCP – Transmission Control Protocol

-Header is 20 bytes

-Connection Oriented Protocol(Makes sure the packets get there and numbers them in order) Sends one packet and waits for conformation before sending another packet. Has error checking!!

-Three way handshake/Ending handshake

-Packets stream(can cut packets whenever it wants, doesn’t have to be full packets at once) can always resend packets

-Good for files or text documents

NotepadCommunication Protocols:UDP

UDP- User Datagram Protocol

+smaller packets then TCP 

+Packet Header is only 8 bytes

+Connectionless protocol doesn’t make sure the packets make it. (Just keeps sending) no error checking

+Sends in logical chunks

+Good for streaming 







NotepadNetworking Protocols

Networking Protocols

+Needs to know if it is in TCP or UDP 

+What port is it traveling over



NotepadNetworking Protocols: Telnet, SMPT, POP3 & IMAP

-Telnet- Port 23- UDP/TCP

+Remote terminal


-SMTP – Port 25- TCP (Sending Emails)

+Simple Mail Transfer Protocol (Emails)

-POP3- Port 110 – TCP (Downloading Emails)

+Post Office Protocol 3

+Doesn’t send Email but does receive Emails by downloading the email from server to client via program.

+Will delete Email from server after client receives mail but can be configured to retain the information of both sides. 

-IMAP – Port 143 – TCP (Downloading Emails)

+Downloads message from server to client but will also keep a copy on the server.

+More robust and has more fetchers then POP3


NotepadNetworking Protocols:DNS, HTTP & HTTPS

-DNS- Port 53- TCP/UDP most of the time UDP (Domain Name Service)

+FQDN to IP(Fully Qualified Domain Name)

+www.google.com to

-HTTP-Port 80- TCP (Hyper Text Transfer Protocol)

+Send/Receive Command/Info to web servers

+Uses Clear Text that’s insecure(Anyone can see the information over your network with programs such as wireshark)

-HTTPS-Port 443- TCP


-HTML(Hyper Text Markup Language)

+The language of the internet <body>, <P>, Link address exe.. 


NotepadNetworking Protocols:FTP, TFTP & SFTP

*Need to know  that protocols go with what ports

-FTP- Port 21- TCP (File Transfer Protocol)

+File Transfer Protocol(No coding protocols) just sent over the net

+File Transfer w/minimal overhead

-TFTP-Port 69- UDP (Trivial File Transfer Protocol)

+sometimes set to multiple clients at once

-SFTP-Port 22- TCP

+Secure File Transfer Protocol (Is encrypted)

+SSH Encryption (requires encryption keys on both sides)



NotepadNetworking Protocols:RDP Remote Desktop

 RDP- Port 33389- TCP/UDP

+Remote Desktop (Windows OS)

NotepadOther Protocols: DHCP,LDAP,SNMP,SMB/CIFS & SSH

-DHCP (Dynamic Host Configuration Protocol)

+Automatically allows our computer to receive a IP, subnet mask, DNS & other settings

-LDAP (Lightweight Directory Access Protocol)

+Connect w/Directory Servers (Active Directory)

-SNMP (Simple Network Management Protocol)

+Allows us to connect with several different devices… switches/router/printer/exe.

-SMB/CIFS (Sever Message Block/Common Internet File System)

+Allows us to connect to servers and access files exe.

+Mainly used for File servers

-SSH (Secure Shell)

+encrypted using shared keys between client and server

+Command Line Control over a system



-65,535 ports

- (80 is the port) just like teamspeak

-Allows us to have multiple network connections over one network.

Different Layers(Our ports work on the Transport layer)






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