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Abstract

This paper introduces a STIgmergy based Routing protocol (STIR) for Content Centric Delay Tolerant Networks. STIR makes the most of spatio-temporal interactions between nodes to set up bio-inspired gradient fields between content producers and content users. STIR routing follows this gradient field to efficiently route information in Delay Tolerant Networks. The validation of this protocol has been coupled with the definition of a new mobility parametric model that makes possible to easily express the preferential locations and movements commonly observed in real human mobility traces. Performance evaluations by simulations demonstrate that STIR delivers better performances than traditional protocols even in case of highly dynamic networks.

Abstract

Rate-based congestion control, such as TFRC, has not been designed to enable reliability. Indeed, the birth of TFRC protocol has resulted from the need for a congestion-controlled transport protocol in order to carry multimedia traffic. However, certain applications still prefer the use of UDP in order to implement their own congestion control on top of it. The present contribution proposes to design and validate a reliable rate-based protocol based on the combined use of TFRC, SACK and an adapted flow control. We argue that rate-based congestion control is a perfect alternative to window-based congestion control as most of today applications need to interact with the transport layer and should not be only limited to unreliable services. In this paper, we detail the implementation of a reliable rate-based protocol named Chameleon and bring out to the networking community an ns-2 implementation for evaluation purpose.

Abstract

In the context of a reconfigurable transport protocol framework, we propose a QoS-aware Transport Protocol (QSTP), specifically designed to operate over QoS- enabled networks with bandwidth guarantee. QSTP combines QoS-aware TFRC congestion control mechanism, which takes into account the network-level band- width reservations, with a Selective ACKnowledgment (SACK) mechanism in order to provide a QoS-aware transport service that fill the gap between QoS enabled network services and QoS constraint applications. We have developed a prototype of this protocol in the user-space and conducted a large range of measurements to evaluate this proposal under various network conditions. Our results show that QSTP allows applications to reach their negotiated QoS over bandwidth guaranteed networks, such as DiffServ/AF network, where TCP fails. This protocol appears to be the first reliable protocol especially designed for QoS network architectures with bandwidth guarantee.

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Abstract

The proliferation of laptops, cellular phones, and other mobile computing platforms connected to the Internet has triggered numerous research works into mobile networking. The increasingly dense set of wireless access networks that can be potentially accessed by mobile users open the door to an era of pervasive computing. However, the puzzle of wireless access networks that tends to become the natural access networks to the Internet pushes legacy "wire-oriented" communication architectures to their limit. Indeed, there is a critical gap between the increasingly used stream centric multimedia applications and the incapacity of legacy communication stacks to insure the continuity of these multimedia sessions for mobile users. This paper proposes a generic communication architecture (i.e. not dedicated to a specific protocol or technology) that aims to fill the gap between the application layer continuity needs and the discontinuity of the communication service inherent to the physical layer of wireless mobile networks. This paper introduces an end to end communication architecture that preserves efficiently session continuity in the context of mobile and wireless networks. This architecture is mainly based on end to end mechanisms that could be integrated into a new generation reconfigurable transport protocol as defined in [20]. The proposed contribution efficiently satisfies mobility requirements such as efficient location management, fast handover, and continuous connection support.

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