Quality of service support, security and OSPF interconnection in a MANET using OLSR, Journal of Telecommunications and Information Technology, 2008, nr 2

The MANET networks are of prime interest for military networks. One of the proeminent routing protocols for MANET is OLSR, and indeed, OLSR has been used in many evaluations and experiments of MANETs. As OLSR is on its way to standardization, there are still a number of extensions that are useful and sometimes necessary for practical use of OLSR networks: such extensions are quality of service support, security, and OSPF interconnection. In this paper, we present the architecture, design, specifications and implementations that we made to integrate these features in a military test-bed. This test-bed is a real MANET comprising 18 nodes. These nodes communicate by radio and use the IEEE 802.11b MAC protocol. The OLSR routing protocol updates the routing table used by the IP protocol to forward packets

Optimal Number of Message Transmissions for Probabilistic Guarantee in the IoT

International audienceThe Internet of Things (IoT) is now experiencing its first phase of industrialization. Industrial companies are completing proofs of concept and many of them plan to invest in automation, flexibility and quality of production in their plants. Their use of a wireless network is conditioned upon its ability to meet three Key Performance Indicators (KPIs), namely a maximum acceptable end-to-end latency L, a targeted end-to-end reliability R and a minimum network lifetime T. The IoT network has to guarantee that at least R% of messages generated by sensor nodes are delivered to the sink with a latency ≤ L, whereas the network lifetime is at least equal to T. In this paper, we show how to provide the targeted end-to-end reliability R by means of retransmissions to cope with the unreliability of wireless links. We present two methods to compute the maximum number of transmissions per message required to achieve R. M F air is very easy to compute, whereas M Opt minimizes the total number of transmissions necessary for a message to reach the sink. M F air and M Opt are then integrated into a TSCH network with a load-based scheduler to evaluate the three KPIs on a generic data-gathering application. We first consider a toy example with eight nodes where the maximum number of transmissions M axT rans is tuned per link and per flow. Finally, a network of 50 nodes, representative of real network deployments, is evaluated assuming M axT rans is fixed. For both TSCH networks, we show that M Opt provides a better reliability and a longer lifetime than M F air, which provides a shorter average end-to-end latency. M Opt provides more predictable end-to-end performances than Kausa, a KPI-aware, state-of-the-art scheduler

Optimal Number of Message Transmissions for Probabilistic Guarantee in the IoT

International audienceThe Internet of Things (IoT) is now experiencing its first phase of industrialization. Industrial companies are completing proofs of concept and many of them plan to invest in automation, flexibility and quality of production in their plants. Their use of a wireless network is conditioned upon its ability to meet three Key Performance Indicators (KPIs), namely a maximum acceptable end-to-end latency L, a targeted end-to-end reliability R and a minimum network lifetime T. The IoT network has to guarantee that at least R% of messages generated by sensor nodes are delivered to the sink with a latency ≤ L, whereas the network lifetime is at least equal to T. In this paper, we show how to provide the targeted end-to-end reliability R by means of retransmissions to cope with the unreliability of wireless links. We present two methods to compute the maximum number of transmissions per message required to achieve R. M F air is very easy to compute, whereas M Opt minimizes the total number of transmissions necessary for a message to reach the sink. M F air and M Opt are then integrated into a TSCH network with a load-based scheduler to evaluate the three KPIs on a generic data-gathering application. We first consider a toy example with eight nodes where the maximum number of transmissions M axT rans is tuned per link and per flow. Finally, a network of 50 nodes, representative of real network deployments, is evaluated assuming M axT rans is fixed. For both TSCH networks, we show that M Opt provides a better reliability and a longer lifetime than M F air, which provides a shorter average end-to-end latency. M Opt provides more predictable end-to-end performances than Kausa, a KPI-aware, state-of-the-art scheduler

Journal of Telecommunications and Information Technology, 2008, nr 2

kwartalni

Quality of Service Routing in a MANET with OLSR

http://www.jucs.orgAd hoc wireless networks have enormous commercial and military potential because of their self-organizing capacity and mobility support. However, some specificities of these networks such as radio interferences and limited resources make more complex the quality of service (QoS) support. Indeed, on the one hand, the bandwidth offered to users is strongly affected by radio interferences. On the other hand, flooding information in such a network must be optimizedin order to save resources. Therefore, we propose in this paper, a solution taking into account radio interferences in mobile ad hoc network routing and optimizing flooding. This solution is based on a modified version of the OLSR routing protocol that considers bandwidth requests and radio interferences in the route selection process while providing a very efficient flooding.A comparative performance evaluation based on NS simulations shows that despite the overhead due to QoS management, this solution outperforms classical OLSR in terms of QoS perceived by the users (e.g. bandwidth amount granted to a flow and delivery rate). The efficiency of the optimized flooding is equal to that provided by the native version of OLS