Reaching the Islands with MOOC: Store-and-Forward Approach
One of the challenges to implement MOOC (Massive-Open-Online-Course), or any eLearning methods, in the rural areas is that we need to deal with the situation where continuous network connectivity is not available due to the lack (or low availability) of telecommunication infrastructure. To put it into context, for Sam Ratulangi University, the COMPETEN-SEA Project is targetting people who live in three islands regencies in North Sulawesi Province, Indonesia. The province is located at the northest part of Indonesia, near the border with the Phillipines. The three regencies are Sitaro, Sangihe and Talaud, with the total area of about 39,000 km2, with population about 315,000. These regencies have 155 total number of islands, 43 of the them are inhabited, with ten of these islands are categorized by the goverment as remote and outer islands (Figure 1).
The economy of the people who live in these islands depends on the marine and coastal sectors. However, the fishing business is usually small scale with low capital, because the fish processing industries are mostly located in the main island, in Bitung or Manado city, which are far away from these island so it is costly in terms of transportation. And storing the fish is not an option, because of the supply of electricity in the islands usually depends on diesel generator, not enough to power a cooling storage to store the fish for a long time. So it is a kind of dilematic for the islands community as even though the fish are richly provided by the sea, by they cannot get enough benefit from that.
The solution that we proposed is, we need to develop/strengthen entrepreneurship skills for the people in the islands, especially the skills that are related with the processing and marketing of fisheries products. So, through COMPETEN-SEA Project, we want to develop a MOOC on entrepreneurship, targetting the fisherman family who live in these three islands regions of North Sulawesi Province.
Coming back to the problem of connectivity, although most of the main islands are connected to the Internet, at least with cellular data network, but some of the smaller islands are still difficult to reach the Internet. In this article I will focus on the effort to connect and deliver the MOOC material with how we reach this smaller islands.
Our solution is to use store-and-forward data delivery on the DTN (Disruption-Tolerant Network). The basic idea behind DTN network is that the endpoints are not always continuously connected. DTN uses store-and-forward approach in order to transfer data between the endpoints. The store-and-forward data delivery could be done in various ways, for example (see Figure 2):
- by foot, in which the data in one server is stored wirelessly in a portable device like a smartphone or Raspberry pi, and then transported by human to the other server in the remote area, and then completing the transmission; Another approach is called Sneaker-net (https://en.wikipedia.org/wiki/Sneakernet), that use a passive device like USB flashdisk, or harddrive, to transmit the data between computers,
- by vehicles, in which the data carrier could be a car or bus, traversing from one server location to the other on land, for example from the main city to the small villages, or
- by ship (like what we use in our project), that travel or passing near the island where the remote server is located.
Our design use case is shown in the Figure 3. As you can see, in this design we use ships or ferries that are the main transportation means between the mainland to the islands. Everyday we usually have at least one or two trips, either from Manado or Bitung city, to the islands. The routes are served either by the private companies or government-owned company (PELNI). Our idea is to utilized these ships as data carrier from the mainland or main islands, where the Internet is available, to islands where any of the telecommunication means is not available. The use case is as follows:
- On the ship, we have a small computer running on Raspberry pi, where the teacher could put the materials that will be transported to the audience, the students, who are located at the islands.
- When the ship start the trip and traversing near the islands at a certain distance, the computer on the ship will build a connection wirelessly, using a long-range WiFi connection, to another computer (also running on Raspberry Pi) at the island. There will be a delta-t, which is a time duration of connection that we could use either for transmitting or receiving data to/from the island. The whole process is done automatically every time the ship traversing near the islands.
- When the ship reach the place where Internet is available, the updated from the island could be synchronized back to teacher site.
In conventional and dedicated network, LMS (Learning Management System) is commonly utilized and installed in a centralized server to be accessed by multiple clients, usually through the Internet. To implement e-Learning in the rural areas where the locations could spread in huge distributed places, we could have a local LMS server that can be accessed locally in each of that area, and then to establish integrated learning environment among these areas, we would need to synchronize these LMS servers, at least at the database level. Since we are dealing with a non-continuously connected network here, then the challenge is how to implement multiple LMSs synchronizations in the DTN context.
There are some factors the we need to consider in this situation:
- Portability: the system need to be possible for physically transported between places. Ideally, the system need to be powered with battery and small enough to be carried anywhere.
- Low cost: implementation in rural area requires the system to be cost-effective.
- Fast synchronizing: whenever an ad-hoc connection is established between two LMSs, the synchronization process needs to be done automatically and as fast as possible because there’s no guarantee that the connection will be available for a long time.
By considering above factors, we chose to deploy the Moodle LMS that run on Raspberry Pi system. In fact, we use MoodleBox (Figure 4) which is a ready-made Moodle 3.4 platform on Raspberry Pi that can turn into Wi-Fi accesspoint to provide direct access to clients in the range of a few meters. It’s enough to serve the learning content for a household. The system could be powered with a power-bank via USB cable, with that we could run the system continuously one or two days per charge. The Raspberry Pi system and power-bank could be combined in one integrated body to provide easiness in transport.
Cost is another reason we chose Raspberry Pi-based system such as Moodlebox. In Indonesia, the cost for a complete Raspberry Pi 3 model B system is around USD 56, including the shipping fee. So it is quiet cheap, but usable for our use case.
In the DTN context, many times the connection is limited in terms of time, so it is important to use the connection time as efficient as possible. For example, the synchronization between two LMSs should only take place when there are differences in the database, so that we can minimize the data interaction when the connectivity is available. Because all of the data updates are timestamped, then we could know which data is updated or added after the last synchronization. Then we could build a dumpfile that includes only of those updated data. This file, together with other media files such as image, audio or video, should be compressed first before sending to the other server. By doing this we could save the bandwidth and increase the datarate.