Synchronizing Asynchronous Learning

Combining Synchronous and Asynchronous Techniques

Tom Worthington

Research School of Computer Science, Australian National University, Canberra, Australia

For ICCSE 2013, 28 April 2013, Colombo, Sri Lanka. Plus MOOCs with Books: Singapore 24 April, CSIRO Seminar Room at ANU 8 July and ACS Canberra 12 November.
Slides and notes:

Description: On-line learning uses the terms synchronous and asynchronous to describe tools and learning activities. This research looks into the origins of these terms, their use today and asks if these are the correct terms to use and if the use of these terms has held up the development of better tools and techniques. It is proposed that the use of syncronisation of asynchronous learning is particularly applicable to address issues with large scale e-learning, such as Massive Open Online Courses (MOOCs).

Keywords: Asynchronous Learning; Synchronous Learning; Electronic Learning; Web Conference; Videoconferencing; Pedagogy; Massive Open Online Courses, MOOC.

Please cite as:

Worthington, T. (2013). Synchronizing Asynchronous Learning: Combining Synchronous and Asynchronous Techniques. In Proceedings of 2013 8th International Conference on Computer Science & Education (ICCSE), 26 Apr - 28 Apr 2013 , Sri Lanka. URL:

Preprint available at:

Acknowledgment: This work started as a literature review for the University of Southern Queensland course "Online Pedagogy in Practice" (EDU8114). My thanks to Dr Petrea Redmond of the USQ Faculty of Education, for her patience in helping a computer programmer with pedagogy.

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Tom Worthington FACS CP

Tom Worthington

Tom Worthington is an IT consultant and course designer for vocational and postgraduate university courses. In 2010 he was awarded Canberra ICT Educator of the Year by the Australian Computer Society, for his work on sustainable e-learning. Tom is an Adjunct Senior Lecturer at the Australian National University. In 1999 he was elected a Fellow of the Australian Computer Society for his contribution to the development of public Internet policy and previously worked for the Australian Government. He is a Past President, Honorary Life Member, Certified Professional and a Certified Computer Professional of the society as well as a voting member of the Association for Computing Machinery and a member of the Institute of Electrical and Electronics Engineers.


From computing:

“Of a computer or part of one: not operating in accordance with clock signals; (of operations) beginning when the previous operation finishes, rather than occurring at regular intervals of time...” (a. asynchronous, OED)

The term synchronous in everyday use refers to “Existing or happening at the same time ... belonging to the same period” (a. synchronous, OED). Asynchronous is defined as “Not synchronous; not existing or occurring at the same time, not coinciding in time...” (a. asynchronous, OED). The terms originated in medicine and were then adopted in computing: “Of a computer or part of one: not operating in accordance with clock signals; (of operations) beginning when the previous operation finishes, rather than occurring at regular intervals of time...” (a. asynchronous, OED).

Use of the Terms in e-Learning

Synchronous e-learning emulates a traditional face-to-face classroom.

Hrastinski (2008) defines synchronous for on-line learning using the examples of videoconferencing and text chat. Asynchronous is defined by reference to e-mail and discussion boards and that asynchronous e-learning does not require teachers and students to be on-line “at the same time”. The definition of synchronous on-line learning would appear to agree with the dictionary definition, being concerned with events happening at the same time. However, the second part of Hrastinski's description of synchronous e-learning, provides a different description: “in real time”.

Benbunan-Fich (2012) refers to synchronous and asynchronous modes of education being used “... depending on whether the communication is carried out in real time or in delayed time...” and “... real time (synchronous lectures) or delayed time (asynchronous lectures) ...”. Thus the on-line event emulates a traditional classroom, where the teacher and students are at one location, able to speak to each other and share learning materials.

Synchronized Asynchronous

Large (video) files can be sent in advance (“Store and forward”in computer terminology) and played when required, or in educational terms: synchronized asynchronous.

It should be noted that all communication involves a delay in transmission. This delay is not perceptible in a classroom, but can become significant for on-line distance education. Ibrar (2012) reports that for India's satellite based on-line education, the Round Trip Time (RTT) from ground station to satellite and back to the ground can be 250 milliseconds. If the signal needs to be relayed further, such as through a terrestrial wireless network the delay and be several times this and disrupt normal conversation.

While not directly related to latency, Ibrar also describes overcoming limitations in the satellite system by sending large video files in advance of being used for a class. The interactive part of the class is then delivered via a terrestrial low bandwidth network and the locally stored video played as required. Such computer systems are described as “Store and forward”, the term also used for e-mail and bulletin board system (what in on-line learning is referred to as asynchronous).

The sending of material in advance to be used later at a specific time could be referred to as synchronized asynchronous.

Synchronous Learning

Important educational interactions:

  1. Asynchronous
    • learner – learner(s)
    • teacher – learner (“Learning to teacher”)
    • learner – material (“Learning to content”)
  2. Synchronous
    • teacher – learner

Soo (1998) and Anderson (2008).

Information diffusion analysis or Quantitative Data Analysis (QDA) of student discussion? (Agrawal, et al 2012 and Dreon and McDonald 2012).

Much of traditional education is synchronous, in the dictionary meaning of the word: students are provided a timetable of what they need to do and when. Students then synchronise their activities by reference to a calendar and clock, without the need for high speed electronic communications. Also many classroom activities are asynchronous, in that individual students, or groups, are performing different activities at the same time, or the same activities at different times.

Soo (1998) explores the concept of “interaction” in on-line distance education, using the Delphi technique with a group of education experts. Eight categories of interaction were identified, being permutations of synchronous/asynchronous, learner/teacher and material/self reflection/learner. The Delphi process found the important educational interactions were Asynchronous: learner – learner(s), teacher – learner and learner – material. The next most important was Synchronous teacher – learner. The least important were Synchronous learner interactions.

Anderson (2008) emphasizes the learner centric and social nature of on-line learning. However, their arguing that the on-line environment is a unique cultural context is overstating the case. Academics have used written communication for a culture of scholarship, long before the invention of the Internet.

In defining on-line learning, Anderson highlights the importance of "Interaction", with the "Educational interactions" model proposed identifying “Learning to content”, “Learning to teacher”, “learner to learning”, amongst other interactions. However, a simpler model could have just people communicating with each other, via any available media (such as a computer bulletin board, or a book).

Siemens (2005) equates three learning terms with epistemological terms:

  1. Behaviorism to objectivism: What is produced with education is an observable change in student behavior, as part of objective reality.
  2. Cognitivism to Pragmatism: Learning comes from doing practical exercises and thinking about that experience, not just abstract study of concepts.
  3. Constructivism and Interpretivism: The learning takes place when the student builds their own internal model of the topic of study.

Principles of connectivism are listed, including diversity of opinions, connecting information sources, Capacity to know, continual learning, and decision-making as a learning process. One principle which appears at odds with the others is: "Learning may reside in non-human appliances".  Coward (2009) reports how investigation of the physiology of the brain provides insights into how the brain works as well as a way to emulate it in software. This may provide new insights which could be applied to education.

Kop and Hill (2008) ask if learning theories, and connectivism in particular, meet the needs of learners and will do so in the future. The role of the " learning community" in connectivism is  emphasized. The paper goes on to describe "Epistemological Frameworks for Learning" and "Compatibility of Connectivism and Formal Education". The paper concludes by suggesting a "radical discontinuity" due to a flood of new on-line sources of information, which be particularly problematic for schools, which are less Connectivist than higher education.  The paper ends by suggesting a "paradigm shift" may be occurring, but does not say what it is.

The flood of new on-line information source's predicted by Kop and Hill has occurred, but without the predicted paradigm shift. The news media on-line sources mimic traditional broadcast and print publications. The limited interactivity provided is similar to the store and forward forums provided in educational software. On-line learning communities use software which supports a similar mode of interaction and appears conventional in format. This may be because on-line educators and tool developers are limited in their thinking by the synchronous/asynchronous dichotomy.

Information diffusion analysis has been applied to investigating how rumors spread through social networks (Agrawal, et al (2012)). The same analysis techniques could be applied to on-line student discussion, to identify what roles students (and the tutors) play in information diffusion in the class. This information could be used to identify when information has spread through the class. This electronic document is a “live” template and already defines he need for a formal test. The result would be a form of synchronization of the asynchronous learning process, identifying when the class has reached a level of understanding of a topic, so they can move on to the next.

Dreon and McDonald (2012) discuss the use of Quantitative Data Analysis (QDA) for a systematic analysis of the discussions in on-line courses to look at the development of critical thinking skills. However, such analysis has up to now only been a research activity, as it required the manual categorization of audio discussions and sufficient computing power for analysis of large amounts of text chat. With advances in transcription software and processing capacity this could now be done in real time, with the tutor (and perhaps the students) receiving an analysis of the discussion.

Combining Synchronous and Asynchronous Techniques

Learning Management (LMS) systems for both at ANU:

Oliver (1999) describes three aspects of what they term "Conventional Teaching": content, activities and implementation. The content is characterized as fixed, linear and structured. The activities are characterized as fragmented, with a lack of context and abstracted. Implementation is said to be teacher as expert, individual learning and discrete assessment.

Oliver contrasts conventional teaching with "Contemporary Teaching", having the inverse characteristics: flexible, unstructured, teacher as coach, outcomes oriented collaborative learning. Oliver was writing from the perspective of 1999. In 2012 post-secondary education, practices have moved toward the contemporary approach envisaged. However, Oliver's view of technology providing flexibility has mixed results. Learning Management (LMS) systems, such as Moodle, reinforce a fixed, linear and structured approach, by offering the course designer only one layout with a list of topics and set dates.

The lack of direct support for real-time learning in the LMS has encouraged a fragmented approach with the class having to switch software packages to move from store-and-forward to real-time mode.

With Oliver's third element "implementation", LMS have had more success, encouraging student discussion forums with the "teacher as coach", facilities for easily creating on-line groups encourages collaborative learning and the ability to easily mark digital artifacts encourages integrated assessment.

An example is the use of Moodle at the Australian National University (ANU). The same LMS is used to teach Sanskrit to small group (Taylor and Beckmann, 2009) and engineering to large classes (Johnson, et al, 2011). The Sanskrit class emphasizes individual performance by the student, in small group, with personal involvement of the teacher as coach. The ANU engineering approach is for a more highly structured courses delivered to large classes of engineering students.

A concept of "asynchronous learning within a synchronous framework" is used by the ANU engineering department. While not mentioned by the authors, this approach may have been inspired by engineering practice, which has regular check points in work, to monitor performance of a system or project. While this project was using "blended" learning (the synchronous components being face-to-face), the same approach should be applied to a pure on-line course which used a combination of synchronous and asynchronous tools.

Synchronous Learning With Near-Real-Time Comms

Face-to-face teaching is not "real-time": repeating important points, pausing for effect (Synchronous techniques used: show of hands, summing up, Q&A).

Same syncronisation techniques are used in virtual classroom (Isaacs and Tang, 1994)

Delay of a few seconds makes the system more efficient and flexible

On-line education theorists have assumed that synchronous learning requires “real-time” communication with no perceptible delays. However, near-real-time communication, with delays of several seconds, may better emulate a classroom situation, be educationally useful and also reduce the resource requirements on computers and networks.

In a face-to-face classroom there is not constant instant communication between all those present.  As an example, a teacher does not expect an instant answer to a question from every student simultaneously. Face-to-face teaching practices take into account the asynchronous aspects of the classroom, with repeating important points several times, pausing for effect, summing up, calling for a show of hands and calling for answers, to achieve occasional synchronization.

Cowan (2008) complied estimates of bandwidth used by the Wimba Classroom virtual classroom software product. A typical 40 minute Wimba session with the student watching video required 20kBps and 46.88MB. An interesting aspect of this is the lower bandwidth and total data for pre-recorded sessions (16kBps and 37.5MB). This is because better compression can be used. Just as students can assimilate information better if given more time, so can computers.

What was not mentioned by Cowan was the latency and reliability required for a real-time session. Store and forward systems are less susceptible to communications problems. A relatively simple near-real-time enhancement could be made to store and forward systems, such as Moodle and eliminate the need for completely separate real-time learning package, such as Wimba Classroom.

Real-time learning applications provide emulation of face to face class using audio, video and display of educational materials in real time. These features were available in previous video conferencing systems. Isaacs and Tang (1994) reported that a delay of more than one half-second on a video conference disrupted the usual verbal negotiation of turn-taking in a conversation, at which point participants begin to use gestures, such as holding up a hand for attention. The 2012 Follow the Sun on-line conference used formal verbal cues “Over to you now Tony...” (MIJS76, 2012). Learning applications have added features to emulate the gesture of a student raising their hand for attention, or to take a poll. These polling functions are used to synchronize the class: the teacher will wait until most students have replied to the poll and then report the results. This is a way to ensure that the focus of the class is on one point.

Synchronised Asynchronous Constructivist Learning

Airport by Iain Anderson (2005) made using DOT pictograms

HTML5 can synchronize text, images, audio and web content: WebVTT (Hickson, 2012).

LMS records activity times (Moodle)

Audio and video cab be synchronized with the LMS, bridging synchronous and asynchronous e-learning

Relaxing the "real time" limit allows for student reflection

The new web standard, HTML5, includes provision for synchronizing text, images, audio and other web content. One example is Web Video Timed Text (WebVTT) to synchronize closed captions for the deaf with  video (Hickson, 2012). A WebVTT text file contains start and stop times in microseconds for each the text caption. There is no requirement for the video, or the caption file to be transmitted real time, as synchronization is performed using a clock. HTML5 also includes provision for synchronizing other web content, such as web pages.

LMS, such as Moodle, already have some real time features. All activities by participants are logged with the time from a clock and some activities (such as forums, quizzes and assignments) can have start and end time limits. Moodle's instant messaging facility provides a similar service to text chat in Wimba Classroom. Provided a sufficiently fast Internet connection and Moodle server are used,   Moodle can be used for real time learning. Audio and video could be synchronized with the LMS, bridging the gap between synchronous and asynchronous forms of on-line learning.

The combination of synchronous and asynchronous forms of on-line learning could be used to promote a constructivist approach. This could be done by relaxing the current lockstep approach of packages such as Wimba Classroom, where the aim is for all the class to see precisely the same images on screen at precisely the same time. As well as imposing severe limited on the equipment, this also limits the opportunity for the student to build their own internal model by exploring the topic for themselves, as they have to keep up with the live presentation. Relaxing the real time aspect would also the student time for reflection and to be able to explore the materials themselves, within a time limit.

Large Scale Asynchronous e-Learning

or MOOCs with Books

Massive Open Online Courses ( MOOCs):

  1. Massive: 100,000 students, or more.
  2. Open: No scholastic or financial barrier to enrollment.
  3. On-line: Materials delivered and students interact via the Internet.
  4. Course: One semester, one quarter full time student load (a US course).

This postscript was added after preparation of the formal paper for ICCSE 2013. Massive Open Online Courses ( MOOCs) have recently been widely discussed in education forums and this is now spreading to the business and general media. These large scale courses present problems which synchronised asynchronous e-learning can help overcome.

It should be noted that MOOCs are an adaption of existing e-learning techniques, just using a different business model. The MOOC business model assumes that giving as way a product "free" on-line will attract revenue in other ways, such as students enrolling in other conventional courses. It is likely that this model will fail for most providers, resulting in a collapse of MOOC course offerings around the end of 2013. Similar to the previous Dot-com bubble, this will likely result in the bankruptcy of most for-profit and non-profit MOOC ventures and some universities. However, the idea of free open access to some course materials will likely survive.

Some characteristics of an MOOC are:

  1. Massive: 100,000 students or more. Australia's large university has less than 50,000 students.
  2. Open: No scholastic or financial barrier to enrollment. Materials may also be open educational resources.
  3. On-line: Materials delivered and students interact via the Internet.
  4. Course: Similar in size to an Australian university subject of about a 12 week semester one quarter full time student load (a US course). But does not provide a credential on completion.

Some MOOC Suppliers

Some MOOC Courses

Introduction to Computation and Programming Using Python by John V. Guttag
  1. Harvard edX CS50x: Introduction to Computer Science
  2. MIT edX 6.00x: Introduction to Computer Science and Programming (uses an optional textbook)

It should be noted that the MIT edX course 6.00x: Introduction to Computer Science and Programming uses a conventional textbook. The textbook (Introduction to Computation and Programming Using Python, by John V. Guttag) is optional and is purchased separately from a bookstore, not from MIT.

Software and Training for MOOCs

Implications of MOOCs for Universities

What is a MOOC?

  1. Massive: Systems and software need to scale to deliver materials, provide automated student support and ways for students to interact.
  2. Open: Wider range of students will need more help. Ways for students to find their group needed.
  3. On-line: Ways to support students who have limited and intermittent Internet access are required.
  4. Course: Will need to integrate with conventional university programs or create a whole new on-line university system. Ways to credential students on-line are required (edX Proctored Examinations through Pearson VUE).

Adapting Traditional Courses for Online Use with books

ICT Sustainability: Assessment and Strategies for a Low Carbon Future
eBook by Tom Worthington

Apply traditional synchronized asynchronous pedagogy to MOOCS:

  1. Books: Course content provided in a down-loadable standalone structured modules (textbook), using existing e-Book formats (HTML5, eBook IMS Content Package).
  2. Formative Feedback: Short tests can be used to aid learning by student (SCORM/HTML5).
  3. Groups: Students can be formed into groups for mutual support, on-line and off-line.

The scaling problems of massive on-line learning can be addressed using traditional synchronized asynchronous pedagogy, or "MOOCs with Books". On-line courses tend to present material in small chunks which the designer decided on. These present problems for the learner in terms of context and control. They also place demands on the server and communications network performance and reliability. The format of a traditional textbook, translated to an e-Book (such as ICT Sustainability) provides a carefully structured set of materials for a course, which can be used off-line. Existing e-Book formats can be used (HTML5, eBook IMS Content Package).

Formative Feedback and much of the interaction for the course can also be provided off-line using existing formats (SCORM/HTML5). Plug-ins and upgrades can be provided for existing LMS software, such as Moodle (and e-portfolios such as Mahara), to allow modules to be downloaded and used offline, with students checking back in later with their progress. This will greatly reduce the loads placed on these systems, allowing for millions of students. Software for large scale e-learning can be quickly developed by using existing e-learning and e-book standards (web, Moodle Book Module, EPUB, IMS Content Package, SCORM Package). Of-line support can use the features already built into HTML5 and also features for support of mobile devices.

Open Source e-Portfolio software

The Australian Computer Society (ACS) uses e-portfolios and mentors alongside on-line postgraduate courses in the ACS Computer Professional Education Program (CPEP). The ACS also uses e-portfolios and on-line examinations for Migration Skills Assessment, on behalf of the Australian Government.

Using e-portfolios requires new skills of the student and also of the assessors. These skills will be required of professionals in the workplace and so should be included in postgraduate professional programs.

Up until now, universities have tended to use paper based forms, word processing documents, or bespoke computer applications to record student progress. An example of this evolution is the Student Practice Evaluation Form (SPEF) system. This is currently a paper based system used for recording the progress of occupational therapy students at Australian universities. It is being implemented as a web based application.

Mahara is a free open source e-portfolio package widely used alongside Moodle. This combination can be used assist with recording progress with skills which do not fit neatly into discrete courses.

It should be noted that free open source software can be hosted on a server at the educational institution, or remotely (in "the cloud").

More Information

QR Code for These Notes
  1. The presentation notes are at: and machine translated into Chinese: 大规模开放式网络课程与书籍同步异步学习
  2. Slides for these notes are also available
  3. Demonstration of Using Moodle for Postgraduate Professional Education with eBooks and Smart phones
  4. See also: WORTHINGTON, T. 2012. A green computing professional education course online: designing and delivering a course in ICT Sustainability using Internet and eBooks. 7th International Conference on Computer Science & Education. Colombo, Sri Lanka: IEEE. URL:
  5. Tom Worthington

Version 1, 15 April 2013, Tom Worthington

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