Broadband has boosted e-learning with video-streaming and videoconferencing services. Streaming allows you to distribute lessons to many users during real-time videoconferencing interactions. Here is a picture of the central systems
The e-learning systems consist of hardware and software technologies that enrich traditional learning processes by offering students and teachers new school, academic and professional education tools.
What is e-learning: meaning and characteristics
An e-learning system offers the following basic functionalities:
- be accessible via the Internet, allowing the attendance of distance courses;
- provide for learning paths based on textual, audio, and video multimedia material;
- carry out continuous monitoring of the activities carried out by students;
- submit learning level assessment tests;
- allow interaction between students and professors through exchanging messages or a videoconference system.
The increase in computing, memory, and data storage potential obtained on devices such as personal computers, tablets, and smartphones, in conjunction with the availability of broadband Internet connections, has allowed the creation of E-Learning services that can be accessed by hundreds of thousands of students geographically dispersed in a heterogeneous way.
The best e-learning platforms
Khan Academy, created in 2006 by Salman Khan, is a non-profit organization that offers free online courses based on video lessons uploaded to the YouTube portal.
Coursera was created in 2011 by professors Andrew Ng and Daphne Koller of Stanford University; it involves a hundred universities; allows you to obtain official certificates of course attendance by registering for a fee on a verification platform.
Udacity: created in 2011 by Sebastian Thrun, David Stevens 3 and Mike Sokolsky; each course consists of video lessons accompanied by evaluation tests; allows the issuing of an official certificate of attendance for a fee.
How an e-learning platform works
From the analysis of the characteristics offered by these best e learning platforms, some common features can be seen:
- video lessons broadcast in streaming;
- intermediate and final assessment tests;
- possibility of interaction between students and teachers.
The learning process implemented by the E-Learning systems is mainly based on on-demand video streaming systems (YouTube in most cases), which reach thousands of connected users through a network connection. Internet and a standard web browser. The remote platforms must also integrate learning paths through the organization of the material offered to users and by creating assessment tests that teachers must be able to insert, modify, and intuitively.
One of the open-source platforms explicitly created to provide E-Learning services is Moodle (Modular Object-Oriented Dynamic Learning Environment), created by Martin Dougiamas in 2002. Unlike the platforms mentioned above, Moodle allows you to download and modify the service’s source code, allowing complete customization and integration with existing systems. As in the systems seen above, video lessons can be uploaded by connecting to external providers such as YouTube, or the video can be uploaded as material attached to the study.
The video streaming for e-learning
Video lessons are an essential feature that allows e-Learning services to improve the courses’ quality and reach a wider audience of students. It is necessary to highlight how users’ most widespread E-Learning systems are based on on-demand video lessons (i.e. pre-recorded content). Still, none implements a video distribution system, delegating the task to portals like YouTube. The distribution of video content massively on the Internet requires a large number of computing resources for encoding the uploaded videos, storage for storage and bandwidth for distribution to end-users. Furthermore, to guarantee the highest quality to end-users, it is necessary to use automatic adaptation systems of the distributed video quality, which allow you to dynamically vary the resolution and quality of the video depending on the size of the screen—the device used in reception and of the available band.
The most used Internet streaming systems are HTTP Live Streaming proposed by Apple (HLS) and MPEG Dynamic Adaptive Streaming over HTTP (MPEG-DASH). Both HLS and DASH define formats for the representation of audio and video information that allow you to index various versions of the same video encoded at different resolutions and quality. These descriptions are downloaded when users play the video through the browser. Through the use of standardized technologies based on the W3C consortium (Media Source Extensions – MSE), modern browsers can download video indexes, automatically decide the quality level to be played and start the download of video fragments (chunks) that are reproduced in a meaningful manner within the same web page, without the need to install third-party applications or plugins. The ability to view video streams within common web browsers has considerably increased video traffic on the web. According to the Cisco report [CVN15], the percentage of video traffic compared to total data traffic on the Internet will increase from 73% in 2016 to 82% in 2021.
Video conferencing services for e-Learning
The technologies standardized by the W3C consortium and already available to all users through common browsers include, in addition to streaming video streams directly within web pages, the possibility of establishing audio/video connections in real time between one or more users (videoconference).
The set of technologies that allow real-time communication through browsers has developed within the WebRTC framework. The key feature of this framework is the standardization process that involves developers. This process has led to the definition of an interoperable service between all major browsers (Google Chrome, Mozilla Firefox, Microsoft Edge and Apple Safari), allowing users to make video calls without installing additional software on both devices desktop and mobile. It is essential to underline that video conferencing systems to connect students with professors are not currently provided for in the most popular e-Learning systems, leaving the task to be free or paid services developed by third parties.
The use of these services could further improve the quality of the lessons, allowing:
- the conduct of lectures at a distance in real-time;
- the verification of the results obtained through a remote examination session.
The advantages of studying with online learning
The adoption of video streaming and video conferencing systems for distributing content on the Internet is constantly on the rise, thanks to the increase in available bandwidth computing resources and the standardization of formats and communication protocols. The e-Learning services can benefit from these systems allowing them to overcome the current limits for the performance of didactic activities.
In particular, the approach based on video streaming allows lessons to be distributed to a large number of users. In contrast, the system based on video conferencing allows real-time interaction between students and teachers.