In the context of computing or network in particular, the bandwidth is the total amount of data that can be communicated in a specified amount of time from source to destination. An internet connection with large bandwidth can transfer the data or files in a shorter period of time than an internet connection with low bandwidth capacity. The term bandwidth is applicable to both wired and wireless networks and is measured in bits per second(bps) or Megabits per second(Mbps) or Gigabits per second (Gbps).
Types of Bandwidth
Symmetric Bandwidth
In this type of bandwidth, the amount of data that travels or communicated between two points is same in volume or speed. In terms of internet, symmetric bandwidth means the data capacity will be same in both uploading and downloading of files. The common example of symmetric communication is Cable internet connection or fiber optics network which is available in many cities. Video conferencing is a good example of an application that needs symmetric bandwidth for buffer-free transfer of video files.
Asymmetric Bandwidth
In asymmetric bandwidth type, the amount of data communicated per second is not the same in both directions. ADSL (asymmetrical Digital Subscriber Line) is a perfect example of this type of bandwidth where the downstream data flow is much higher than upstream data transfer. In ADSL broadband internet connection, the download speed is high compared to upload speed since a user needs to download media and other files whereas the upload requests only include a request to access URLs.
Bandwidth Requirements
How much bandwidth do you need? This can be correctly answered only if you are clear about your application needs. For example, if you need to open your emails, Facebook or browse the internet, you can go for ADSL internet connection or in other words you require a low bandwidth. But in case, you have a requirement of videoconferencing or want to run FTP connection or any such requirement where you have to upload large files on the cloud or another portal, you will definitely need a symmetric bandwidth of large bandwidth. Optical Fiber or cable internet is the best internet solution in this scenario.
How does it Work?
Have you seen a water-pipe? The data flows the same way as the water flows in a pipe from one point to other. If the size (diameter) of the pipe is large, more water will flow and if it is small, less amount of water can travel in a specified time period. Similar is the case with data or Network bandwidth.
If your internet download speed is 10 Mbps that mean you can download a file sizing 10 megabytes in one second in standard optimum conditions (no data-loss). If there are more users on the network using same internet connection, the available bandwidth will be divided between them. So in a large network setup, Network administrators have to manage the bandwidth across the network. By using network monitoring and bandwidth control tools, they can limit the bandwidth at some nodes and allow large bandwidth to some other users as per the application requirements.
Thanks @brandonkcochrane!