Since I am working with networking and computers, I need to have some basic knowledge about protocols and what they are. In one way, it’s the worst, since all these abbreviations are complicated and very technical. On the other side, they are such a big part of computing and networking, so you quickly learn the most important ones.
But what is a protocol really? In short, it’s a set of rules in networking. Protocols are making sure that both sides of a conversation (let’s say a client and a server) speak the same language and handle information the same way. Without protocols, all computers and servers would handle things differently and nothing would work together.
Protocols have existed since the end of the 1960’s and since then, many protocols have been created and updated. Many protocols are common things that the everyday user would recognize while other protocols are more techy. Come along for a ride when we take a deep dive into protocols and check out some common protocols.
What is a Protocol?
To help computers talk to each other, there needs to be some form of standard communication that both computers know. This is what protocols are defining. A protocol is basically a set of rules that define how the communication between two computer or other devices will talk to each other.
There is a long list of protocols that define how the communication should work. Many of these protocols are something that you are familiar of already, like WiFi or Bluetooth. These are what you could call Wireless Network Protocols. This is why WiFi in an ASUS laptop and in an Apple iPhone works the same way, even if they are different devices with different manufacturers; because a protocol exists.
When looking at many of the names in networking like TCP, UTP, IP, HTTP, FTP and so on, there is always a P in the end. That P stands for protocol, which means that all these functions above are a protocol. This is because everything has to be standardized if it should work with many different devices.
Who Decides About Protocols?
Before the internet existed, during ARPANET, engineers needed some form of documentation. In 1969, an internet engineer named Steve Crocker invented something called Request for Comments, or RFC for short. RFC was invented to record unofficial notes during the development of ARPANET. However, it has become more than that since.
RFCs are today the official documentation for the internet. In this documentation, you can find internet specifications, events or protocols. There are a couple of organizations that are handling the RFC documentation, like IETF, IRTF or IAB.
These are also the types of organizations that are deciding about protocols but in their own different genre, so to speak. For example, the organization that is deciding about the Bluetooth-protocol is the Bluetooth Special Interest Group (Bluetooth SIG) while the HTTP protocol is being handled by Internet Engineering Task Force (IETF).
5 Common Protocols for Networking
As you might know by now, there is a lot of protocols when it comes to networks, computers, and communication. It’s impossible to list them all but l would still like to expand the most common protocols that are being used in networking today. If you are interested to learn more about networking protocols, Wikipedia has a great collection-page where you can read more on protocols.
If you are on this website, you have probably heard of HTTP. In fact, if you are on any website, you have probably heard of HTTP. HTTP stands for Hypertext Transfer Protocol and is a network protocol for the web. This is the type of protocol that the web browser you are using and the web server that the website is on, is using to communicate with each other.
HTTP was created in the 90s and has since then been updated several times. In 2015, the latest HTTP standard was approved by IESG (Internet Engineering Steering Group), the HTTP 2.0 or HTTP/2. HTTP/2 comes with several new features that improve the speed of HTTP, making it faster to reach the website you want.
A problem with HTTP is that the communication between the browser and the server is unencrypted. Because of this, HTTPS (HTTP Secure) exist. This is an extension of the original protocol but with HTTPS, the communication is encrypted, thus making is much more secure, as the name suggests. If you see a green lock-icon in your web browser URL field, the connection to the web server is secure, using HTTPS.
TCP/IP is actually two protocols that are working together to make sure that everything is going where it’s supposed to without any faults on the way. TCP stands for Transmission Control Protocol and is a protocol used in anything that has to do with the internet, like routers, computers, phones, laptops and much more.
When you are sending a message over Facebook or a Skype chat, the TCP will split that message into bits and pieces and make packages out of it. These packages are then sent over to the destination using the internet. Once at the destination, the packages can be unpacked, and the message can be put together again. This is because the transmission control protocol handles both the packaging and unpacking, making sure that the sender and the receiver understand each other.
The Internet Protocol (IP) is making sure that the packages mentioned above actually reach the correct destination. As you may know, networks are using IP numbers as their address, so that the network can be identified. How hard wouldn’t it be for your package to reach your house if you didn’t have any address? It’s the same thing with network packages.
The DHCP is that kind of protocol that you never think about but if it didn’t exist, it would be a real hassle every time you had friends over. DHCP stands for Dynamic Host Configuration Protocol and it’s responsible for giving out IP addresses to the devices that connect to the network.
For a device to be able to connect to the internet or use any form of network feature at all, it needs an IP address. When a new device connects to a network, the DHCP server (usually the router) will give the device an IP address as well as other network details such as the DNS server address(es) and the default gateway.
In the configuration settings of a router, you can usually set the range of the IP addresses that DHCP should work with. If you do that, you can make sure that there will be no IP conflicts on your network. This is often not a problem unless you have set some static IP addresses on your network, then I suggest that you make sure these addresses are not in the DHCP range.
If DHCP didn’t exist, you would need to get the MAC address (unique network car identifier on all devices) of your friend’s phone and then go into the settings of your router to manually add an IP address to the phone. For a company with thousands of employees, that would be a huge workload. Thanks, DHCP, for your existence.
The Domain Name System (DNS) is a protocol that is translating IP addresses into names and vice versa. Instead of having to enter the IP address and the port of a web server, you can instead type the address of the website, and DNS servers will work in the background to find the correct web server for you.
You can test this for yourself, by doing the opposite of the above. If you would enter 126.96.36.199/ in your web browser, you would be taken to google.com. DNS servers are working together to get you where you want. The very first DNS server is your router, which will know all the devices in your LAN. When you go to a website, your router will forward the request to a DNS server outside your network, usually the ISP’s DNS.
A DNS can hold a lot of records. This is special pointers that will help the DNS to point in the correct direction. There are, for example, something called MX records. These type or records point to a mail server and is used for email. A (or AAAA) records are used for translating IP addresses (as in the example above) while NS records point to other name servers.
Something we all do is to share files between each other. I bet that many of you are uploading files to OneDrive, Google Drive, Dropbox or any other form of cloud storage. If you do, you are using a protocol called File Transfer Protocol, or FTP for short.
The name of the protocol is pretty much explaining itself. It’s a protocol that is being used for transferring files between a client and a server. The client is often your laptop, your phone or your PC while the server is whatever service you are using (OneDrive, DropBox etc).
When using FTP, you usually need to authenticate yourself with a username and a password. However, FTP has the same problem as HTTP, that the communication and file transfer is unencrypted. To solve this, SFTP (Secure FTP) is often used instead, which will encrypt the username, password and the files being transferred.