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Primary path reservation using enhanced slot assignment in TDMA for session admission.

Koneri Chandrasekaran S, Savarimuthu P, Andi Elumalai P, Ayyaswamy K - ScientificWorldJournal (2015)

Bottom Line: In such cases the QoS session is affected.Many TDMA based reservation mechanisms are proposed but need some improvement over slot reservation procedures.A network topology has been simulated and our approach proves to be a mechanism that admits the session effectively.

View Article: PubMed Central - PubMed

Affiliation: Department of Computer Science and Engineering, Tagore Engineering College, Chennai 600127, India.

ABSTRACT
Mobile ad hoc networks (MANET) is a self-organized collection of nodes that communicates without any infrastructure. Providing quality of service (QoS) in such networks is a competitive task due to unreliable wireless link, mobility, lack of centralized coordination, and channel contention. The success of many real time applications is purely based on the QoS, which can be achieved by quality aware routing (QAR) and admission control (AC). Recently proposed QoS mechanisms do focus completely on either reservation or admission control but are not better enough. In MANET, high mobility causes frequent path break due to the fact that every time the source node must find the route. In such cases the QoS session is affected. To admit a QoS session, admission control protocols must ensure the bandwidth of the relaying path before transmission starts; reservation of such bandwidth noticeably improves the admission control performance. Many TDMA based reservation mechanisms are proposed but need some improvement over slot reservation procedures. In order to overcome this specific issue, we propose a framework-PRAC (primary path reservation admission control protocol), which achieves improved QoS by making use of backup route combined with resource reservation. A network topology has been simulated and our approach proves to be a mechanism that admits the session effectively.

No MeSH data available.


Related in: MedlinePlus

Bandwidth calculation interfered by hidden and exposed terminal problem.
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fig2: Bandwidth calculation interfered by hidden and exposed terminal problem.

Mentions: The purpose of backup route discovery is to find the residual capacity of each and every node in a route. Such a mechanism discovers many routes, among which the efficient routes are selected (the mechanism involved in backup route discovery has been discussed in Section 3.1). The reservation approach in our proposal focuses only on the primary route. When the destination node receives the first RREQ packet of a session, it is considered as the primary path and reservation reply is sent along the reverse direction of the same primary path. When the second RREQ packet is received, this path is not reserved but it will be considered as a backup path thereby sending a normal reply. This reservation process is coupled with backup route discovery. The above facts discussed address how the reservation process integrates the route discovery stage. The reason behind using TDMA for reservation in this paper is that it tolerates the radio interference problem and it holds good in our scenario, since all the nodes share the single common channel. We propose a new approach in TDMA which considers both hidden terminal and exposed terminal problem. A glance on the following example helps us to understand the problem in making reservation. In Figure 2, consider the path from A to C. Here the grey slots depict that they are busy and similarly the white slots are free. Between A and B there are five matching free slots {1, 2, 3, 4, 5} and between B and C there are four matching free slots {3, 4, 5, 6}. If we reserve slots {1, 2, 3} for A to transmit and slot {4, 5, 6} for B to transmit, then the path bandwidth is only three. Suppose that if the other pair D and E are currently using slot 2 to communicate, two possible cases will arise.


Primary path reservation using enhanced slot assignment in TDMA for session admission.

Koneri Chandrasekaran S, Savarimuthu P, Andi Elumalai P, Ayyaswamy K - ScientificWorldJournal (2015)

Bandwidth calculation interfered by hidden and exposed terminal problem.
© Copyright Policy - open-access
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC4385671&req=5

fig2: Bandwidth calculation interfered by hidden and exposed terminal problem.
Mentions: The purpose of backup route discovery is to find the residual capacity of each and every node in a route. Such a mechanism discovers many routes, among which the efficient routes are selected (the mechanism involved in backup route discovery has been discussed in Section 3.1). The reservation approach in our proposal focuses only on the primary route. When the destination node receives the first RREQ packet of a session, it is considered as the primary path and reservation reply is sent along the reverse direction of the same primary path. When the second RREQ packet is received, this path is not reserved but it will be considered as a backup path thereby sending a normal reply. This reservation process is coupled with backup route discovery. The above facts discussed address how the reservation process integrates the route discovery stage. The reason behind using TDMA for reservation in this paper is that it tolerates the radio interference problem and it holds good in our scenario, since all the nodes share the single common channel. We propose a new approach in TDMA which considers both hidden terminal and exposed terminal problem. A glance on the following example helps us to understand the problem in making reservation. In Figure 2, consider the path from A to C. Here the grey slots depict that they are busy and similarly the white slots are free. Between A and B there are five matching free slots {1, 2, 3, 4, 5} and between B and C there are four matching free slots {3, 4, 5, 6}. If we reserve slots {1, 2, 3} for A to transmit and slot {4, 5, 6} for B to transmit, then the path bandwidth is only three. Suppose that if the other pair D and E are currently using slot 2 to communicate, two possible cases will arise.

Bottom Line: In such cases the QoS session is affected.Many TDMA based reservation mechanisms are proposed but need some improvement over slot reservation procedures.A network topology has been simulated and our approach proves to be a mechanism that admits the session effectively.

View Article: PubMed Central - PubMed

Affiliation: Department of Computer Science and Engineering, Tagore Engineering College, Chennai 600127, India.

ABSTRACT
Mobile ad hoc networks (MANET) is a self-organized collection of nodes that communicates without any infrastructure. Providing quality of service (QoS) in such networks is a competitive task due to unreliable wireless link, mobility, lack of centralized coordination, and channel contention. The success of many real time applications is purely based on the QoS, which can be achieved by quality aware routing (QAR) and admission control (AC). Recently proposed QoS mechanisms do focus completely on either reservation or admission control but are not better enough. In MANET, high mobility causes frequent path break due to the fact that every time the source node must find the route. In such cases the QoS session is affected. To admit a QoS session, admission control protocols must ensure the bandwidth of the relaying path before transmission starts; reservation of such bandwidth noticeably improves the admission control performance. Many TDMA based reservation mechanisms are proposed but need some improvement over slot reservation procedures. In order to overcome this specific issue, we propose a framework-PRAC (primary path reservation admission control protocol), which achieves improved QoS by making use of backup route combined with resource reservation. A network topology has been simulated and our approach proves to be a mechanism that admits the session effectively.

No MeSH data available.


Related in: MedlinePlus