⚙️ Network Protocols
A communication protocol is a system of rules that allows two or more entities of a communications system to transmit information via any kind of variation of a physical quantity.
TCP/IP#
Transmission Control Protocol/Internet Protocol
- TCP/IP: A suite of communication protocols used to interconnect network devices on the internet and private networks.
- TCP: A connection-orientated protocol which establishes and maintains a connection until the application programs at each end have finished exchanging messages.
- IP: The method that governs how computers share data across the Internet or private networks. When a device sends data, such as an email or web form, its message gets parsed into smaller packets that contain the sending computers address, and part of the message.
ARP#
Address Resolution Protocol
A procedure for mapping a dynamic Internet Protocol address (IP address) to a permanent physical machine address in a local area network. The physical address is also known as a Media Access Control or MAC address.
DHCP#
Dynamic Host Configuration Protocol
A network management protocol used on UDP/IP networks whereby a DHCP server dynamically assigns an IP address and other network configuration parameters to each device on a network so they can communicate with other IP networks.
DNS#
Domain Name System
A protocol used on internet based and private servers which maintains a directory of domain names and translate them to IP addresses. This is necessary because, although domains names are easy for people to remember, devices access websites based on IP addresses.
FTP#
File Transfer Protocol
A standard Internet Protocol for transmitting files between computers on the internet over TCP/IP connections. FTP is a client-server protocol where a client will ask for a file and a local or remote server will provide it.
HTTP#
Hyper Text Transfer Protocol
The underlying protocol used by the World Wide Web. HTTP defines how messages are formatted abs transmitted, and what actions web servers and browsers should take to various commands
HTTPS#
Hypertext Transfer Protocol Secure
- A secure variant of HTTP
- Adds a layer of security on the data in transit through a Secure Socket Layer or Transport Layer Security protocol connection.
- Enables encrypted communication and secure connection between a remote user and the primary web server.
ICMP#
Internet Control Message Protocol
An error reporting protocol
Network devices such as routers use to generate error messages to the source IP address when network problems prevent delivery of IP packets.
This is also used for the PING command
IMAP#
Internet Message Access Protocols
A standard email protocol that stores email messages on a mail server, but allows the end user to view and manipulate the messages as though they were stored locally on the end users device.
POP3#
Post Office Protocol version 3
A standard mail protocol used to receive emails from a remote server to a local email client. Allows you to download email messages on your local computer and read them even when you're offline.
This is contrast to IMAP
SMTP#
Simple Mail Transfer Protocol
Standard protocol for email services on a TCP/IP network. Provides the ability to send email messages. Application-layer protocol that enables the transmission and delivery of email over the internet
SSH#
Secure Shell OR Secure Socket Shell
A network protocol that gives users particularly system administrators a secure way to access a computer over a unsecure network. Not as secure as VPN
UDP#
User Datagram Protocol
An alternative communications protocol to TCP used primarily for establishing low-latency and loss-tolerating connections between applications on the internet. Connectionless communication ideal for streaming, VOIP or online gaming.
RIP#
Routing Information Protocol
A dynamic routing protocol which uses hop count as routing metric to find the best path between the source and the destination network. Not suitable for larger networks as its limited to a hop count of 15
OSPF#
Open Shortest Path First
A routing protocol for Internet Protocol (IP) networks. Keeps track of a complete topological database of all connections in the local network. No hop count limitation Ideal for traffic engineering purposes, where routes can be constrained to meet quality of service requirements.
Telnet#
Telnet
Telnet is a simple text-based network protocol. Telnet was and is still used by some people to access remote computers over TCP/IP networks, like the internet.
TFTP#
Trivial File Transfer Protocol
A simple protocol that is used for sending a file from the server to the client. Trivial File Transfer Protocol uses the concept of UDP to share files between server and client.