Beaconless position based routing with guaranteed delivery for wireless ad-hoc and sensor networks

Existing position-based routing algorithms, where packets are forwarded in the geographic direction of the destination, normally require that the forwarding node knows the positions of all neighbors in its transmission range. This information on direct neighbors is gained by observing beacon messages that each node sends out periodically. Several beaconless greedy routing schemes have been proposed recently. However, none of the existing beaconless schemes guarantee the delivery of packets. Moreover, they incur communication overhead by sending excessive control messages or by broadcasting data packets. In this paper, we describe how existing localized position based routing schemes that guarantee delivery can be made beaconless, while preserving the same routes. In our guaranteed delivery beaconless routing scheme, the next hop is selected through the use of control RTS/CTS messages and biased timeouts. In greedy mode, neighbor closest to destination responds first. In recovery mode, nodes closer to the source will select shorter timeouts, so that other neighbors, overhearing CTS packets, can eliminate their own CTS packets if they realize that their link to the source is not part of Gabriel graph. Nodes also cancel their packets after receiving data message sent by source to the selected neighbor. We analyze the behavior of our scheme on our simulation environment assuming ideal MAC, following GOAFR+ and GFG routing schemes. Our results demonstrate low communication overhead in addition to guaranteed delivery.1st IFIP International Conference on Ad-Hoc NetWorkingRed de Universidades con Carreras en Informática (RedUNCI

Beaconless position based routing with guaranteed delivery for wireless ad-hoc and sensor networks

Existing position-based routing algorithms, where packets are forwarded in the geographic direction of the destination, normally require that the forwarding node knows the positions of all neighbors in its transmission range. This information on direct neighbors is gained by observing beacon messages that each node sends out periodically. Several beaconless greedy routing schemes have been proposed recently. However, none of the existing beaconless schemes guarantee the delivery of packets. Moreover, they incur communication overhead by sending excessive control messages or by broadcasting data packets. In this paper, we describe how existing localized position based routing schemes that guarantee delivery can be made beaconless, while preserving the same routes. In our guaranteed delivery beaconless routing scheme, the next hop is selected through the use of control RTS/CTS messages and biased timeouts. In greedy mode, neighbor closest to destination responds first. In recovery mode, nodes closer to the source will select shorter timeouts, so that other neighbors, overhearing CTS packets, can eliminate their own CTS packets if they realize that their link to the source is not part of Gabriel graph. Nodes also cancel their packets after receiving data message sent by source to the selected neighbor. We analyze the behavior of our scheme on our simulation environment assuming ideal MAC, following GOAFR+ and GFG routing schemes. Our results demonstrate low communication overhead in addition to guaranteed delivery.1st IFIP International Conference on Ad-Hoc NetWorkingRed de Universidades con Carreras en Informática (RedUNCI

An Approach to Software Architecture Analysis for Evolution and Reusability

Software evolution and reuse is more likely to receive higher payoff if high-level artifacts—such as architectures and designs—can be reused and can guide low-level component reuse. In practice, however, high-level artifacts are often not appropriately captured. This paper presents an approach to capturing and assessing software architectures for evolution and reuse. The approach consists of a framework for modeling various types of relevant information and a set of architectural views for reengineering, analyzing, and comparing software architectures. We have applied this approach to large-scale telecommunications systems, where the approach is useful to reveal areas for improvement and the potential for reuse

Beaconless Position-based Routing with Guaranteed Delivery for Wireless Ad hoc and Sensor Networks 1)

Abstract Existing position-based routing algorithms, where packets are forwarded in the geographic direction of the destination, normally require that the forwarding node should know the positions of all neighbors in its transmission range. This information on direct neighbors is gained by observing beacon messages that each node sends out periodically. Several beaconless greedy routing schemes have been proposed recently. However, none of the existing beaconless schemes guarantee the delivery of packets. Moreover, they incur communication overhead by sending excessive control messages or by broadcasting data packets. In this paper, we describe how existing localized position based routing schemes that guarantee delivery can be made beaconless, while preserving the same routes. In our guaranteed delivery beaconless routing scheme, the next hop is selected through the use of control RTS/CTS messages and biased timeouts. In greedy mode, the neighbor closest to destination responds first. In recovery mode, nodes closer to the source will select shorter timeouts, so that other neighbors, overhearing CTS packets, can eliminate their own CTS packets if they realize that their link to the source is not part of Gabriel graph. Nodes also cancel their packets after receiving data message sent by source to the selected neighbor. We analyze the behavior of our scheme on our simulation environment assuming ideal MAC, following GOAFR+ and GFG routing schemes. Our results demonstrate low communication overhead in addition to guaranteed delivery. Key words Beaconless routing, geometric routing, guaranteed delivery, sensor networks

Spawning Networks

The deployment of new network architectures, services, and protocols is often manual, adhoc and time consuming. In this paper we introduce "spawning networks", a new class of programmable networks that automate the life cycle process for the creation, deployment and management of network architectures. These networks are capable of spawning distinct "child" virtual networks with their own transport, control and management systems. A child network operates on a subset of its "parent's" network resources and in isolation from other spawned networks. Spawned child networks represent programmable virtual networks and support the controlled access to communities of users with specific connectivity, security and quality of service requirements. In this paper we present a framework for the realization of spawning networks based on the notion of the Genesis Kernel, a virtual network operating system capable of creating distinct virtual network architectures on-the-fly. We discuss the motivation and principles that underpin spawning networks and focus on the design of the transport, programming and life cycle environments, which comprise the main architectural components of the Genesis Kernel. 1