Suchergebnisse

Through providing a historical overview of border disputes between Vietnam & neighboring Laos & Cambodia in Indochina, the article aims to evaluate the success gained by Vietnam in its efforts to secure the western & southwestern land border & thus maintain a peaceful external environment for the domestic reform. Since the Cambodian endgame, Vietnam has sought to improve political relations with all neighbors (including China) &, on that basis, consistently applied fundamental principles of international law while adopting the region's common practice in order to resolve border issues. In return, the Communist leadership in Laos & the Hun Sen regime in Cambodia have been eager to sustain the Cold War border treaty system with Vietnam in order to stabilize the border, address cross-border non-traditional security issues, & ensure Vietnam's assistance for economic development & regime security. In addition, Vietnam's border disputes with Cambodia prove harder to deal with because the latter's domestic power struggle has turned the issue into a political card played by opposition parties in their election campaigns. References. Adapted from the source document.

Through providing a historical overview of border disputes between Vietnam and neighbouring
Laos and Cambodia in Indochina, the article aims to evaluate the success gained by Vietnam in its
efforts to secure the western and southwestern land border and thus maintain a peaceful external
environment for the domestic reform. Since the Cambodian endgame, Vietnam has sought to
improve political relations with all neighbours (including China) and, on that basis, consistently
applied fundamental principles of international law while adopting the region's common practice
in order to resolve border issues. In return, the Communist leadership in Laos and the Hun Sen
regime in Cambodia have been eager to sustain the Cold War border treaty system with Vietnam
in order to stabilize the border, address cross-border non-traditional security issues, and ensure
Vietnam's assistance for economic development and regime security. In addition, Vietnam's border
disputes with Cambodia prove harder to deal with because the latter's domestic power struggle
has turned the issue into a political card played by opposition parties in their election campaigns.

Delay Tolerant Networks (DTNs) are sparse mobile ad-hoc networks in which there is typically no complete path between the source and destination. Content retrieval is an important service in DTNs. It allows peer-to-peer data sharing and access among mobile users in areas that lack a fixed communication infrastructure such as rural areas, inter-vehicle communication, and military environments. There are many applications for content retrieval in DTNs. For example, mobile users can find interesting digital content such as music and images from other network peers for entertainment purposes. Vehicles can access live traffic information to avoid traffic delay. Soldiers with wireless devices can retrieve relevant information such as terrain descriptions, weather, and intelligence information from other nodes in a battlefield.In this dissertation, we propose the design of a secure and scalable architecture for content retrieval in DTNs. Our design consists of five key components: (1) a distributed content discovery service, (2) a routing protocol for message delivery, (3) a buffer management policy to schedule and drop messages in resource-constrained environments, (4) a caching framework to enhance the performance of data access, and (5) a mechanism to detect malicious and selfish behaviors in the network. To cope with the unstable network topology due to the highly volatile movement of nodes in DTNs, we exploit the underlying stable social relationships among nodes for message routing, caching, and placement of the content-lookup service. Specifically, we rely on three key social concepts: social tie, centrality, and social level. Centrality is used to form the distributed content discovery service and the caching framework. Social level guides the forwarding of content requests to a content discovery service node. Once the content provider ID is discovered, social tie is exploited to deliver content requests to the content provider, and content data to the requester node. Furthermore, to reduce the transmission cost, we investigate and propose routing strategies for three dominant communication models in DTNs: unicast (a content is sent to a single node), multicast (a content is sent to multiple nodes), and anycast (a content is sent to any one member in a group of nodes).We also address several security issues for content retrieval in DTNs. In the presence of malicious and selfish nodes, the content retrieval performance can be deteriorated significantly. To address this problem, we use Public Key Cryptography to secure social-tie records and content delivery records during a contact between two nodes. The unforgeable social-tie records prevent malicious nodes from falsifying the social-tie information, which corrupts the content lookup service placement and disrupts the social-tie routing protocol. The delivery records from which the packet forwarding ratio of a node is computed, helps detect selfish behavior. Furthermore, we propose a blacklist distribution scheme that allows nodes to filter out misbehaving nodes from their social contact graph, effectively preventing network traffic from flowing to misbehaving nodes.Through extensive simulation studies using real-world mobility traces, we show that our content retrieval scheme can achieve a high content delivery ratio, low delay, and low transmission cost. In addition, our proposed misbehavior detection method can detect insider attacks efficiently with a high detection ratio and a low false positive rate, thus improving the content retrieval performance.

Introduction : Agent Orange, Rural Development, and Enduring Farmers -- Changing Vietnam and Farmers -- Development, Agriculture, and Farmers -- Agent Orange and Vietnamese Farmers : A Distant Legacy -- Farmers in Post-Doi Moi Vietnam -- Health and Elusive Risks -- Health and the Farmers : Whose Responsibility Counts? -- Farmers' Logic : Loss Aversion -- Seed for Action, Seed for Change.