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Extended Scenario and User Stories

To create our user-stories, we will follow the Serval Project’s long focus on post-disaster response and recovery among the general public. We will thus imagine a situation where a community has had infrastructure damaged, and is without functioning communications infrastructure to reliably connect them to the outside world. Of course this scenario has strong parallels to what we see when people are living in regions of unrest as well, so it’s a good starting point for us. The following user-stories will walk us through an extended scenario in such a post-disaster situation. All names and locations are fictitious.

2.0 Scenario Background

The communities of Ulia, Luania, Saua and Kiatu live on, Tija, a long and thin island of 800 square kilometres at the northern end of the archipeligo, some 400km from the national capital of Ari Ula, and 90km from the next nearest populated island. The 3,500 people living on Tija enjoy life on their tropical island, located in the South Pacific. Kiatu, the regional capital, is the largest population centre on the island, with a population of just over 2,000 living in the town and surrounding villages. There is 4G cellular coverage in the town centre, with 2G coverage extending out to the surrounding villages. The cellular service, including internet access, is connected to the rest of the country via a VSAT satellite link. Luania is the nearest of the other communities to Kiatu, although it is still some 15km away. Depending on weather conditions, can sometimes use mobile phones from on the top of a nearby hill, that has line of sight to Kiatu. Saua is 7km on the other side of Luania from Kiatu, and has no cellular network access. Ulia is yet another 12km further on from Saua, and also lacks cellular coverage. There are NGOs or small government presences in Saua and Ulia, who have HF radios, that are used to provide a basic level of communications back to Kiatu and the national capital.

Tija’s location in the southern tropical zone of the Pacific exposes it to considerable geophysical hazards, including cyclone, tsunami and earthquake, like many other Pacific Island Countries. GDP per capita is relatively low, yet as has become common around the world, almost all families and most adults have access to a low-end smart-phone. The relative expense and difficulty accessing mobile internet means that the population is quite familiar with “side loading” of applications on their Android phones, as is the case in many Pacific Island Countries. The Tijans have a strong community structure based around traditional chiefdoms in each of the four communities, and work constructively with one another whenever disasters strike.

Because of their vulnerability, and isolation from conventional communications, a number of residents in each of the four communities on Tija already use the Serval Mesh peer-to-peer software on their Android smart-phones.

Our scenario begins with a 7.2 magnitude earthquake that causes substantial damage, especially in Kiatu, which is nearest to the epicentre. Fortunately the earthquake triggers only a relatively small tsunami, and there is no immediate loss of life. However the combination of the earthquake and tsunami have destroyed the cellular infrastructure and its satellite earth-station. It will likely take the mobile network operator a couple of weeks to restore service, as they are also having to proritise restoration of service to larger communities nearer the national capital.

2.1 Forming a community

With conventional communications to the outside world down, the Tijan communities need to find their own ways to communicate, so that they can coordinate their own response to the disaster, and generally keep their communities functioning as effectively as possible.

The larger community in Kiatu is particularly keen to enable local businesses to continue trading, and to ensure that the limited local resources can be readily used where required, e.g., building materials required to repair infrastructure, as well as the people required to undertake such work. They also have a need to identify where infrastructure is damaged, so that they have the situational awareness that will enable them to be effective in their response. Knowing where damaged infrastructure is will also be helpful for re-routing traffic and ensuring public safety.

The smaller out-lying communities are also keen to ensure that local communications is possible, so that they can ensure the well-being of their communities, and collate information about any damaged infrastructure so that this can be communicated to the regional and national capitals, so that remedial works can be carried out when the expected foreign aid support starts to flow into the country.

To support this, in each of the communities someone opens the Serval Mesh app, and uses the Create Community function to create a new local community on the mesh network. As well as a community name, a shared secret is set up that is required by participants who wish to contribute material into the community, but reflecting the friendly socio-political environment on Tija, the communities are set up to allow read and search access without needing the shared secret. Also in the smaller communities, the shared secret is set to something quite simple, such as 1234, as the communities prioritise ease of access over security.

In Kiatu, the larger population means that several different people have attempted to create the community, resulting in some initial confusion. Later in the day, the regional administration select one of those communities to be the official Kiatu earthquake response community on the Serval Mesh. Nonetheless, it takes a few days for almost all members of the dupliate communities to switch to the official community. These problems do not emerge in the smaller communities, as their populations are small enough that the normal village meeting mechanisms are able to lead a unified approach in each community.

At this point, there are four primary communities that have been created: Official Kiatu Earthquake Response, Ulia Earthquake, Luania Together, and Saua Saua. This is inaddition to the short-lived duplicate communities in Kiatu: Kiatu Earthquake Help, Earthquake Help, and Kiatu Together. However, there are relatively few users in each. Initially, the duplicate Kiatu communities have more users than the official community, reflecting the ability of grass-roots organisation to be faster than government processes, especially following a disaster.

2.2 Building a community

After creating the communities, individuals within those communities approach others and ask if they have joined the new communities, and explain to them how the communities can help them, by allowing the collection and sharing of information of relevance to them. For those who do not yet have the Serval Mesh on their phone, they side-load the application using the bluetooth tools for doing so that they are already familiar with, or they use the wifi-based sharing mechanism in the Serval Mesh app.

This process continues until all community members who wish to join a community have joined.

2.3 Searching for communities

Some community members don’t wait until someone invites them, but use the Search for communities function in the Serval Mesh app to find communities. Most users use the Find communities that my contacts are in function to do this in a safe way, that avoids the risk of seeing offensively named communities. Some users choose to search through all available communities, after clicking on a confirmation that unprotected searching may result in them seeing offensive material. Either way, when they find the community that they are looking for, they use Join Community, and if they make an error, or wish to otherwise leave a community, they use the Leave community function.

As members of the communities have family and friends in the other villages on Tija, they use the Search for communities function to discover and join the other communities that have been setup on Tija. Among those is Neire, who lives in Ulia.

2.4 Searching for people: User discovery

Neire helps to look after her grandmother, Iu. Neire helps her grandmother setup the Serval Mesh on her phone, and helps her to join the Ulia Earthquake community. She then uses the find users function, with the search scope set to only look for people in my community, to find herself on Iu’s phone, and to find Iu on her phone. They confirm that they can send each other text messages and voice messages. Neire then helps Iu to find other relatives who have joined the community, and adds them all to Iu’s contact list, so that she can easily communicate with them.

2.5 Searching for services: Service & Data discovery

Neire is helping with the recovery effort. As she can drive, the village chief allows her to use the village‘s truck to help move people and goods, as required. Neire uses the offer service function to advertise to each of the communities the availability of freight and transport services for the next three days. She offers this for free.

The truck has only a ¼ of a tank of Diesel, so Neire uses the service search feature to search for available sources of diesel fuel. She also uses the publish request feature to announce that she is looking for diesel fuel. Using this, after a short time, she receives a resource match alert, that contains a list of current offers for diesel fuel that have been made in the communities that she is participating in. She thus discovers that there is some diesel available in Saua, and prepares to head to Saua. Before departing, she searches the list of published requests from the Saua community.

By this time, more people have had time to make requests, and she discovers that Saua is running short on fresh drinking water, because the earthquake has damaged some of their water tanks, and the tsunami has caused contamination of several other water tanks. Neire thus arranges with others from her village to cart 900L of drinking water in a variety of containers. One of the other community members uses the offer resources function to announce the availability of ample fresh drinking water in Ulia. Finally, Neire and several of her extended family set off to Saua with the water, and to collect the diesel.

2.6 Searching for data/information: Data discovery

Other members of the communities use the search published requests and search services functions, both to find resources that they need, as well as to understand what resources and services they might be able to provide to meet unmet needs.

Boli from Luania notices that there are unmet requests for diesel fuel, because the only offers for diesel fuel are from a few community members who have diesel in portable containers. Boli assumes that this means that the fuel distribution centre in Kiatu was damaged in the earthquake or tsunami. Boli and several others in Luania have coconut plantations, and have hand-presses for extracting the oil from coconuts, which can be used in adapted diesel engines, provided that the weather is warm enough that it doesn’t solidfy. Fortunately, the tropical climate on Tija means that this is a very rare event. Boli thus uses the publish service and offer resources functions to offer diesel fuel and fueling services. Boli and the other coconut plantantion managers arrange for the production of several hundred litres of oil over the next 24 hours, and keep an eye on demand through customers and through the search published requests function.

2.7 Searching for places: Mapping and geoinformatic discovery

Meanwhile, Neire and her team are making their way down towards Saua. Along the way, they discover several places where the road has been damaged due to rock slides or erosion from the tsunami. Neire has one of her team use the crowd-sourced mapping function to mark these locations on the map, so that others will know about the damage, allowing them to avoid it, or to begin work on repairing them. Some of the damage is quite near to Saua, and after Neire arrives, she shows some of the people in Saua how to use the crowd-sourced mapping to search for damaged infrastructure, and search for resource offers to find the materials that they need to start repairing the worst of the damage.

Neire uses the crowd-sourced mapping to navigate to the locations where people had requested fresh drinking water and helps distribute this. She is also able to efficiently plan her route to include collecting the diesel fuel. The recipients of the water use the cancel resource request after they receive the drinking water. They have in the meantime logged their damaged water tanks on the crowd-sourced mapping function. After Neire has collected the diesel fuel, that offer is also removed, using the update resource offer function.

Neire now has enough diesel fuel to respond to several other requests for moving materials around Saua, including helping the road repair volunteers get their tools and materials to the nearest damaged location. She knows that she will still need more fuel, and has been keeping an eye on the resource match alert function, and discovers the offer of coconut oil for use as diesel substitute. She uses the Serval Mesh‘s MeshMS text messaging function to make arrangements to collect 300 Litres of coconut oil, enough to fuel her truck for the next couple of days. Because she is able to communicate with Boli, she knows when the coconut oil will be ready, and is able to help with other recovery activities beforehand. The crowd-source mapping function also lets her discover ahead of time the condition of the road, and allow sufficient time to get there, and to bring some repair materials and volunteers to stabilise the worst of the damage.

Neire arrives at Luania in the early evening, soon after Boli has her fuel ready. Neire uses the search for services function to find a place where she and her team can spend the night, before they continue helping their communities the next morning.

2.8 Searching by low-literacy user

Not everyone on Taji has a high level of literacy. Yeco is an older man in Luania who lives on his own when his family travel to Kiatu for work. This is the case following the earthquake. His family have not been able to return from Kiatu yet, as a bridge has been damaged by the earthquake, making the road impassible. However, Yeco is able to exchange voice messages with his family sporadically, as people walk from Luania and Kiatu to opposite sides of the damaged bridge, allowing messages to be automatically exchanged via the Serval Mesh. Thus Yeco and his family know that one another are safe. However, Yeco’s kitchen has been damaged, and so he will require assistance finding nutritious food. Based on instructions from his family, he opens the crowd-sourced mapping function, and uses emojis attached to the service offers and resource offers to find someone nearby who is offering food. He sends them a voice message asking if they can bring him some food. They ask him in a voice message to use the share location function, which he does, thus enabling them to deliver him food until his family are able to return from Kiatu.

2.9 Searching by visually impaired user

Ado is another elderly person living in Luania, and while she is literate, her eyesight has deteriorated over the years, making it very difficult for her to read. She is, however, able to use the vision impaired interface option to access basic functions of the Serval Mesh. This provides a text-to-speech interface, which allows her to access and send voice messages to her contacts. She also requires assistance with obtaining food while her family are busy with the recovery efforts. She is able to send them voice messages to let them know how she is going, and set their minds at ease, and that she has used the vision impared interface to listen to the various resource offers, and thus find someone nearby who is able to provide her with nutritious food, and to communicate with them using voice messages.

2.10 Summary

The above scenario and its embedded user stories show how communications in these sorts of situations can be very effective at helping vulnerable communities. The combination of the existing Serval Mesh functions, with the ability to share, discover and request services and resources makes it much easier for isolated communities to respond efficiently and with effective situational awareness in ways that have not previously been possible. Now our challenge is to collate the functions required to enable these improvements, and map them to the Serval Mesh‘s delay-tolerant networking primitives.

content/searchanddiscoveryscenario.txt · Last modified: 30/09/2022 04:04 by Paul Gardner-Stephen