6 research outputs found
AODV-UI with Malicious Node Detection and Removal for Public MANET
A node in Mobile Ad-hoc Network (MANET) solely depends on neighbor nodes for its connectivity to the outer networks. It is completely different with fixed network connection where a central infrastructure is providing connectivity to the outside network for all mobile nodes there. This kind of situation makes MANET easier to build rather than fixed network with certain infrastructure. However, this nature of MANET makes it very vulnerable to various attacks, especially by nodes within the MANET that is called malicious nodes. This paper provides a preliminary result for MANET security enhancement based on AODV-UI routing protocol. In this work we implement an algorithm to detect and remove malicious nodes in AODV-UI routing protocol. We evaluate our work in different scenarios by varying the number of nodes, the number of malicious node, the sending rate of the node in concern, and the type of the attack i.e. route poisoning, black hole, packet spoofing. Our experiment shows that on average, an attack can be completely removed within 0.48 seconds in the worst case, with the traffic rate of 100 kbps, and 0.04 seconds in the best case, with the sending rate of 10 kbps
Adaptive multi-polling scheduler for QoS support of video transmission in IEEE 802.11e WLANs
The 802.11E Task Group has been established to enhance quality of service (QoS) provision for time-bounded services in the current IEEE 802.11 medium access control protocol. The QoS is introduced throughout hybrid coordination function controlled channel access (HCCA) for the rigorous QoS provision. In HCCA, the station is allocated a fixed transmission opportunity (TXOP) based on its TSPEC parameters so that it is efficient for constant bit rate streams. However, as the profile of variable bit rate traffics is inconstant, they are liable to experience a higher delay especially in bursty traffic case. In this paper, we present a dynamic TXOP assignment algorithm called adaptive multi-polling TXOP scheduling algorithm (AMTXOP) for supporting the video traffics transmission over IEEE 802.11e wireless networks. This scheme invests a piggybacked information about the size of the subsequent video frames of the uplink streams to assist the hybrid coordinator accurately assign the TXOP according to actual change in the traffic profile. The proposed scheduler is powered by integrating multi-polling scheme to further reduce the delay and polling overhead. Extensive simulation experiments have been carried out to show the efficiency of the AMTXOP over the existing schemes in terms of the packet delay and the channel utilization