In this study we examine the history and growth of ICTD since the 1990s. We underline the trends defining this research field and examine the progress in research areas that have come to dominate discussion in ICTD through a thorough literature review of the last decade of ICTD work. In order to answer questions pertaining to the rigor, impact and significance of ICTD, and to compare the expectations and perceived achievements with respect to different development goals, we interview 50 expert ICTD researchers and practitioners. We analyze these results to understand stakeholders' opinions on the past performance of ICTD, both as an academic field and as an area of development practice, and identify defining ideas on the potential directions for the future of ICTD. This study is work in progress and we have continuing research in this area, the subset presented here is rigorous and ready for wider discussion.

Tracking and ensuring disbursements make it to their intended recipients is among the problems development professionals are most concerned about. To examine the potential monitoring role playable by technology, we present RuralScope, an information repository designed to handle the information needs of a newly started welfare scheme offering daily wage payments to over 31 million families in rural India. Since the problem of monitoring development extends beyond project specific needs to a general sense of awareness, RuralScope works on two levels. First, for project auditors, RuralScope acts as an easily searchable, disconnected database of disbursements that helps speed up the audit process. Second, for a more general audience, an organized and annotatable front end for casual viewers, policy-makers, and researchers alike to keep track of documents and data related to the project RuralScope.

We consider the problem of efficientMAC design for long-distance WiFi-based mesh networks. In such networks it is common to find long propagation delays, the use of directional antennas, and the presence of inter-link interference. Prior work has shown that these characteristics make traditional CSMA-based MACs a poor choice for long-distance mesh networks and this finding has led to several recent research efforts exploring the use of TDMA-based approaches to media access. In this paper we first identify, and then address, several shortcomings of current TDMA-based proposals. First, because they use fixed-length transmission slots, current TDMA-based solutions do not adapt to dynamic variations in traffic load leading to inefficiencies in both throughput and delay. As we show in this paper, the throughput achieved by existing solutions falls far short of the optimal achievable network throughput. Finally, due to the scheduling constraints imposed by inter-link interference, current TDMA-based solutions only apply to bipartite network topologies.

This paper examines low-cost computing projects for education in developing regions, and presents some of the common entrepreneurial and technical problems faced by past and current initiatives. In particular, we look at various models of computer usage, and evaluate their appropriateness according to their effectiveness in education, their socio-cultural suitability, and economic feasibility. Based on detailed field studies and interviews conducted in rural Indian classrooms and economic analysis, we show that shared rather than single-user devices constitute a more realistic and sustainable approach for low-cost computing projects targeting children's education.

Despite the increasing number of WiFi-based Long Distance (WiLD) network deployments, there is a lack of understanding of how WiLD networks perform in practice. In this paper, we perform a systematic study to investigate the commonly cited sources of packet loss induced by the wireless channel and by the 802.11 MAC protocol. The channel induced losses that we study are external WiFi, non-WiFi and multipath interference. The protocol induced losses that we study are protocol timeouts and the breakdown of CSMA over WiLD links. Our results are based on measurements performed on two real-world WiLD deployments and a wireless channel emulator. The two deployments allow us to compare measurements across rural and urban settings. The channel emulator allows us to study each source of packet loss in isolation in a controlled environment. Based on our experiments we observe that the presence of external WiFi interference leads to significant amount of packet loss in WiLD links. In addition to identifying the sources of packet loss, we analyze the loss variability across time. We also explore the solution space and propose a range of MAC and network layer adaptation algorithms to mitigate the channel and protocol induced losses. The key lessons from this study were also used in the design of a TDMA based MAC protocol for high performance long distance multihop wireless networks [12].

We propose a system architecture for real-time hardware speech recognition on low-cost, power-constrained devices. The system is intended to support real-time speech-based user interfaces as part of an effort to bring Information and Communication Technologies (ICTs) to underdeveloped regions of the world.Our system architecture exploits a shared infrastructure model. The computationally intensive task of speech model training and retraining is performed offline by shared servers, while the actual recognition of speech is conducted on low-cost hand-held devices using custom hardware.The recognizer is extremely flexible and can support multiple languages or dialects with speaker-independent recognition. Dynamic loading of speech models is used for changing language grammar and retraining, while reprogramming is used to support evolution of recognition algorithms. The focus on small sets of words (at one time) reduces the complexity, cost and power consumption. We design the speech decoder, the central component of the recognizer, and we validate it via a prototype FPGA implementation. We then use ASIC synthesis to estimate power and size for the design.Our evaluations demonstrate an order of magnitude improvement in power compared with optimized recognition software running on a low-power embedded general-purpose processor of the same technology and of similar capabilities. The synthesis also estimates the area of the design to be about 2.5mm2, showing potential for lower cost. In designing and testing our recognizer we use datasets in both English and Tamil languages.

We consider the problem of routing in a delay tolerant network (DTN) in the presence of path failures. Previous work on DTN routing has focused on using precisely known network dynamics, which does not account for message losses due to link failures, buffer overruns, path selection errors, unscheduled delays, or other problems. We show how to split, replicate, and erasure code message fragments over multiple delivery paths to optimize the probability of successful message delivery. We provide a formulation of this problem and solve it for two cases: a 0/1 (Bernoulli) path delivery model where messages are either fully lost or delivered, and a Gaussian path delivery model where only a fraction of a message may be delivered. Ideas from the modern portfolio theory literature are borrowed to solve the underlying optimization problem. Our approach is directly relevant to solving similar problems that arise in replica placement in distributed file systems and virtual node placement in DHTs. In three different simulated DTN scenarios covering a wide range of applications, we show the effectiveness of our approach in handling failures.

We formulate the delay-tolerant networking routing problem, where messages are to be moved end-to-end across a connectivity graph that is time-varying but whose dynamics may be known in advance. The problem has the added constraints of finite buffers at each node and the general property that no contemporaneous end-to-end path may ever exist. This situation limits the applicability of traditional routing approaches that tend to treat outages as failures and seek to find an existing end-to-end path. We propose a framework for evaluating routing algorithms in such environments. We then develop several algorithms and use simulations to compare their performance with respect to the amount of knowledge they require about network topology. We find that, as expected, the algorithms using the least knowledge tend to perform poorly. We also find that with limited additional knowledge, far less than complete global knowledge, efficient algorithms can be constructed for routing in such environments. To the best of our knowledge this is the first such investigation of routing issues in DTNs.