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    Improving node reachability QoS during broadcast storm in Manets using neighbourhood density kowledge (NDK)
    (2008-12) Onifade, O. F. W.; Ojo, A. K.; Lala, O. G.
    The Counter-based scheme was developed to reduce Broadcast Storm problem. However, to be able to maintain high delivery ratio in either a sparse or dense networks, different thresholds are required. Because of the nature of MANETs determining this threshold require a level of dynamism, without which its operation will be marred. Our earlier research work proposed an algorithmic framework to address the BSP problem, using the knowledge of it neighbourhood density to dynamically determine the threshold so as to adapt to both dense and sparse network while limiting the above stated constrains. In this work, we present the simulation result of our attempt to improve reachability of nodes in MANETs using Neighbourhood Density Knowledge (NDK). While the major characteristics of MANETs remain indeterminate behaviours in the number of participating nodes, mobility and sporadic topology changes based on nodal movement, ability of any supporting protocol to function under both sparsely and densely population of nodes. With the Counter based threshold value based on the neighbourhood information, an important metric considered is the reacheability which is defined in terms of the ratio of nodes that received the broadcast message out of the entire node in the network. Overall, the NDK approach performs best on both sparser and dense networks.
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    Angular displacement scheme (ADS): providing reliable geocast transmission for mobile ad-hoc networks (MANETs)
    (2008-08) Onifade, O. F. W.; Ojo, A. K.; Akande, O. O.
    In wireless ad hoc environments, two approaches can be used for multicasting: multicast flooding or multicast tree-based approach. Existing multicast protocols mainly based on the latter approach, may not work properly in mobile ad hoc networks as dynamic movement of group members can cause the frequent tree reconfiguration with excessive channel overhead and resulting into loss of datagram. Since the task of keeping the tree structure up-to-date in the multicast tree-based approach is nontrivial, sometimes, multicast flooding is considered as an alternative approach for multicasting in MANET. The scheme presented in this research attempts to reduce the forwarding space for multicast packets beyond earlier presented scheme and also examine the effect of our improvements upon control packet overhead, data packet delivery ratio, and end-to-end delay by further reduction in the number of nodes that rebroadcasts multicast packets while still maintaining a high degree of accuracy of delivered packets. The simulated result was carried out with OMNeT++ to present the comparative analysis on the performance of angular scheme with flooding and LAR box scheme. Our result showed a better improvement compared to flooding and LAR box schemes.
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    An algorithmic framework for hybrid adaptive protocol (HAP) to manage broadcast storm problems in mobile ad-hoc networks (MANETS)
    (2008-09) Onifade, O. F. W.; Ojo, A. K.; Okiyi, K. U.
    The consequences of pure flooding which is amongst the simplest and the most straight forward approach to performing broadcast include redundant broadcast, contention and collision which are collectively referred to as broadcast storm problem (BSP). This is as a result of the use of plain broadcasting approaches leading to signal overlap in a geographical area with wireless communication. The Counter-based scheme was developed to reduce Broadcast Storm problem. However, to be able to maintain high delivery ratio in either a sparse or dense networks, different thresholds are required. Because of the nature of MANETs determining this threshold require a level of dynamism, without which its operation will be marred. This research work thus proposed an algorithmic framework to address the BSP problem, using the knowledge of it neighbourhood density to dynamically determine the threshold so as to adapt to both dense and sparse network while limiting the above stated constrains.
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    Estimation of outflow discharge from an ungauged river: case study of Awara in Ondo State Southwestern, Nigeria
    (2017-10) Alabi, O. O.; Sedara, S. O.; Adetoyinbo, A. A.; Akinwande, D. D.
    Flooding has become the annual experience of Nigerian cities especially in the southwestern states of country, precisely Ondo state. This study uses Muskingum Cunge method river routing techniques to compute outflow discharge and to determine hydrographs of inflow and outflow pattern of Awara river Ikare Akoko, North east LGA in Ondo State, Southwestern of Nigeria. The Muskingum Cunge method of flood routine reflects the interrelationship existing between the inflow and outflow of river. The average monthly inflow discharge for twenty years was worked on using Muskingum Cunge method of flood routine. Observation from the hydrograph shows th'at inflow peak occurs in the month of April, while the outflow in the same month is very low. This implies that the month of April is a critical month that needs a special attention and there is a need for channelization of this river before the month of April every year, in order to prevent occurrence of flooding whenever there is heavy rainfall.