Project Background The project was initiated among a group of reindeer herders. Why is ICT a matter for reindeer herders? There are egalitarian – same to all – qualities or potentials in ICT, e.g. business and education, taking part in political processes, leisure, social contacts. There are qualities related to the reindeer herders as part of an indigenous population living as minority in four national states – the Sámi. E.g. creating spaces for discourse, promoting own language. Yet, the terms are crucial. If ICT is available only on terms of stationary living much of the potential is lost, because the herding is a semi-nomadic activity.
Potential of ICT In the case of semi-nomadism ICT has great potential. A crucial potential of ICT is to enable overcoming the strains put on reindeer herding communities by the need to adapt to stationary solutions This is a potential because ICT has capacity to overcome boundaries in time and space
Traditional herding Families moving with the herd throughout the year All generations, both genders included
Reindeer herding today The herding continues to require organic organization and constant moving Modernity requires adaptation to mechanical time and stationary living Reindeer herding is nowadays a male dominated business Approximately 10% of professional herders are women
Culture and Knowledge Cultural diversity is a global concern The reindeer herders and Sámi culture in general carry knowledge of how to build a society on scarce resources Sámi cultural landscape is conceived of as wilderness by many others
Problem The Swedish state has established goals that information and communication technologies shall be available to all citizens This is considered necessary for, among other things, democratic and economic reasons Standards for achievement refer to population density and permanent address Both these standards exclude reindeer herders and their families as individuals Both standards also exclude reindeer herding as economy
Potentials inherent in the SNC proposition Technology transfer: opportunity for local people building knowledge and establishing useful contacts new impulses to high-tech research and to industry Insights into contradictions and shortcomings of information and communication technologies: supposed to make time and place irrelevant, yet not available to the nomadic economy post-modern visions of nomadism are challenged by the Sirges example
First Assumptions It is worth getting basic network coverage to people who live in infrastructure challenged areas even if it is not yet possible to use standard off the shelf technology and even if the features provided are not the same features available at the cutting edge of technology use. While capital costs of establishing the network should be kept as low as possible, it is even more critical that the recurrent costs for running the network must be locally sustainable.
Assumptions Because of area size and population density: o Wireline is not a practical solution o GSM and 3G are not practical solutions The undesirability of putting up sufficient antennas in the nature reserves is another consideration. Satellite coverage is expensive, of limited bandwidth and intermittent TV broadcast is available for data delivery in some remote zones WiFi hotspots are possible, but it is not possible, at this point in time, to build a continuous communications zone with WiFi It is possible to build a network composed of WiFi hotspots and wireline access points all connected by mobile relays.
Project Components Community access Email Web access Educational opportunity Business service Herd telemetry Small business opportunities Web sales Software development and support
Project elements Topographical study of area to be covered – this is necessary to understand population flow and geographical characteristics necessary to locate gateways, WiFi hotspots and corridors. WiFi hotspots: Equipment will need to be modified to produce a narrower longer range access.
Project Elements (contd) Since the relay connectivity is intermittent, the network will require delay tolerant networking support including: Application level gateways Routing software to handle the intermittently connected ad-hoc network. Network elements include: Gateways Relays
Initial Project Phases Initial Topographical SW systems for mapping placement of WiFi hotspots Routing software for relay Application level gateway for email Phase result; prototype demo (in lab) Small Field trial Define a region and install WiFi hotspots and corridors Prototype and deploy gateways Prototype and deploy relays Phase result; Test live network in very confined area
Long Term goal After the test phases are completed, the project should be modeled to allow for rapid deployment within the affected communities. Involves: Developing product quality systems Providing education for local residents to train as network system developers and technicians who can install and maintain the network as well as develop it further.
Participation & Education are key goals In order to make the system sustainable, in fact In order to even get the production system off the ground A large amount of involved and trained local talent must be brought into the project early. Ultimately, it must end up a local project in order to be sustainable.
Solution Space Involves: Opportunistic use of any available network substructure Opportunistic use of work being done by IRTF, JPL, NASA and others on Delay Tolerant Networking (DTN) Bundling Specialized routing protocols Using NAT or similar IPv6 private network capabilities Building on web caching technology used by web content distributors (e.g. Akamai)
Opportunistic use of any available network substructure Use of any network infrastructure that is available. Broadband Fixed phone lines GSM/3G Short Wave Radio Digital TV Broadcast (for data delivery) Use of 802.11 hotspots wherever possible and feasible. Use of mobile relays wherever necessary
Requirements for opportunistic networking Requires detailed knowledge of the opportunities. Electricity Wire Wireless Broadcast Requires topographical mapping of geographical domain Requires knowledge of population flow over time
Delay Tolerant Networking (DTN) While most networks are called store and forward networks, they really only store a data for a very short time. In a DTN there may be long periods of isolation where a network node does not have any neighbors, and thus data may need to be stored for a long time. This long latency effects the way applications can use the network, and requires a different transport and routing strategy.
Normal Internet Message sent Now Now +1 sec Now +2 sec Now +3 sec Now +4 sec
Normal Internet Connection In a normal internet connection, the sub-network, in this case a community, is connected for the entire time that communication is ongoing. For example: In an email dialogue: A persons system (the mail client) sends an hello The mail server responds with its own hello The persons system sends the message The mail server acknowledges receiving the message The message is delivered In other words, the dialogue between the client and the server takes place by taking turns across the network. This entire dialogue must be completed within seconds.
In Delay Tolerant Network Message sent Now Now +1 hour Now +3hours Now +6 hours Now +12 hours
In Delay Tolerant Network Due to the lack of a continuous connection in a DTN, the delay makes using the normal procedure impossible. In this case the mail dialogue would be as follows: Persons computer sends Hello and the message Some time later mail server accepts hello and message and sends acknowledgement Some time later persons computer receives acknowledgement.
In other words Instead of having a normal network conversation – similar to a telephone call Participant in a DTN uses a form of communication that is more like sending a letter.
Applications possible in DTN EMAIL WEB with caching File transfer Telemetry Sensor Reading Herd Tracking
Applications not possible in DTN Transaction based, e.g. Internet Banking Airline Reservations Remote use of other computer, e.g. Telnet Applications that require a ongoing spontaneous dialogue IP Telephony
Bundling Gateways In order to allow complete network exchanges to be packaged into a single transaction, a bundling transport technology has been developed. Prototype of basic bundling code has been made available by Intel/JPL & UC Berkeley
Possible Network Scenarios Fixed relay points Mobile relay points
Fixed Relay SNC – Time 0 Internet Relay Internet Connection Point e.g. Jokkmokk Internet Internet Connection Point e.g. Jokkmokk Community A GW Internet Connection Point e.g. Gällivare GW Community C GW
Fixed Relay SNC – Time 1 Relay Internet Internet Connection Point e.g. Jokkmokk Community A GW Community C GW Internet Connection Point e.g. Gällivare GW
Fixed Relay SNC – Time 2 Internet Relay Internet Connection Point e.g. Jokkmokk Community C GW Internet Internet Connection Point e.g. Jokkmokk Community A GW Internet Connection Point e.g. Gällivare GW
Fixed Relay SNC – Time 3 Internet Relay GW Internet Connection Point e.g. Jokkmokk Internet Internet Connection Point e.g. Jokkmokk Community A GW Internet Connection Point e.g. Gällivare Community C GW
Mobile Relay SNC – Time 0 Internet GW Relay Internet Relay Bundles Blue I Green A Red C Internet Internet Connection Point e.g. Jokkmokk Community A GW Community C GW Community B GW
Mobile Relay SNC – Time 1 Internet GW Relay Bundles Blue - I,A Green -A,I Red - C Internet Internet Connection Point e.g. Jokkmokk Community A GW Community C GW Community B GW
Mobile Relay SNC – Time 2 Internet GW Relay Bundles I2,A A,I,C C,A,I Internet Internet Connection Point e.g. Jokkmokk Community A GW Community C GW Community B GW
Mobile Relay SNC – Time 3 Internet Relay Bundles I2,A,C A2,I,C C,A,I,B Internet Internet Connection Point e.g. Jokkmokk Community A GW Community C GW Community B GW
DTN Routing Method Developing probabilistic routing algorithm with Anders Lindgren at LTU Loosely based on Epidemic Routing Effective but expensive Assumption that a node encountered in the recent past is more likely to be encountered again in the future. As relays encounter each other they exchange probabilities for known destinations and then nodes decide whether to pass/accept a bundle for a destination.
DTN Routing Algorithm Probability Based Algorithm - P [0,1] Still under study For each node - P (a,b) = P init except for home node where P (a,b) =1 Upon encounter - P (a,b)= P (a,b) old +(1- P (a,b)old )x P init If no encounter within time threshold P (a,b)= P (a,b) x k [0,1), k - number of timeout units
DTN Routing Algorithm (contd) Transitive property If node A often encounters node B and node B often encounters node C then node C is a good node for forwarding toward node A P (a,b)= P (a,b) old +(1- P (a,c)old )xP (a,b) xP (a,c) x [0,1) - scaling factor
Status of DTN routing development Currently testing simulations of algorithm Working on several protocol operational issues including: Frequency of exchange of probability vectors Acknowledgement policy Bundle deletion policy
Private networks Each community should be able to set up its own addresses IPv4 IPv6 NAT
Caching Technology Assumes that much of what a community want to see on the web can be predicted based on history and thus can be pre-delivered to local caches When a non-cached page is requested, the request should be posted and the user should be informed when the page becomes available. When a request is filled, not only the requested URL should be returned, but a section of the tree below that URL should also be returned.
And finally We have a need We have a possible set of solutions We have started We have long way to go yet.