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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

Route maintenance.
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Related In: Results  -  Collection


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fig3: Route maintenance.

Mentions: The fact behind route maintenance is that the process monitors the primary and backup routes on a regular basis, checking for QoS requirements (session requirements) [12, 13]. In our proposed method, when the primary route fails, the control moves towards the backup path. Here, PRAC makes use of BRQ (backup route query) message that continuously monitors the stability and effectiveness of the backup path. Previous studies show that many other mechanisms use multiple backup routes, which accounts for increase in reliability but also increases the control overhead. But in our model, the possibility of the primary path failure is very low because of the reservation mechanism used, as described before. The control overhead in PRAC model is very low because path monitoring does not comprise many backup paths and instead is done for a single backup path only. In Figure 3 we describe overall route maintenance process. In case of failure of the primary path, in order to maintain the reliability of the network, the backup path is taken. This backup path is herewith considered to be primary and starts reservation process. Since our proposed model uses a single backup strategy, when the backup is taken as primary (in case of failure), then we lack the existence of a backup path (PRAC requires the presence of a primary and backup path always). Hence the source finds a backup path from route cache. As mentioned before, with the use of BRQ message, the route cache is analysed for the best route that accomplishes the session request. When a node receives a BRQ message, it calculates the contention difference (CD). In our maintenance model, we avoid the calculation of contention count. The reason is that the transmission flow along the primary path is likely to reduce the measured available bandwidth along the backup path. Calculating contention count may end up in insufficient metric; hence the contention difference proves to be an optimal method: (6)CD=CSneighbor∩Rbackup−CSneighbor∩Rprimary.The CD should hold a constraint in which BWavail > CD · BWreq. If the above condition fails, then it sends a BRQF message to the source, thereby removing the specific route from route cache. The advantage of PRAC route maintenance is that in the case of both primary and backup path being failed, the source does not go for route recovery process again and instead it makes use of the route cache information [21].


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

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

Route maintenance.
© Copyright Policy - open-access
Related In: Results  -  Collection

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

fig3: Route maintenance.
Mentions: The fact behind route maintenance is that the process monitors the primary and backup routes on a regular basis, checking for QoS requirements (session requirements) [12, 13]. In our proposed method, when the primary route fails, the control moves towards the backup path. Here, PRAC makes use of BRQ (backup route query) message that continuously monitors the stability and effectiveness of the backup path. Previous studies show that many other mechanisms use multiple backup routes, which accounts for increase in reliability but also increases the control overhead. But in our model, the possibility of the primary path failure is very low because of the reservation mechanism used, as described before. The control overhead in PRAC model is very low because path monitoring does not comprise many backup paths and instead is done for a single backup path only. In Figure 3 we describe overall route maintenance process. In case of failure of the primary path, in order to maintain the reliability of the network, the backup path is taken. This backup path is herewith considered to be primary and starts reservation process. Since our proposed model uses a single backup strategy, when the backup is taken as primary (in case of failure), then we lack the existence of a backup path (PRAC requires the presence of a primary and backup path always). Hence the source finds a backup path from route cache. As mentioned before, with the use of BRQ message, the route cache is analysed for the best route that accomplishes the session request. When a node receives a BRQ message, it calculates the contention difference (CD). In our maintenance model, we avoid the calculation of contention count. The reason is that the transmission flow along the primary path is likely to reduce the measured available bandwidth along the backup path. Calculating contention count may end up in insufficient metric; hence the contention difference proves to be an optimal method: (6)CD=CSneighbor∩Rbackup−CSneighbor∩Rprimary.The CD should hold a constraint in which BWavail > CD · BWreq. If the above condition fails, then it sends a BRQF message to the source, thereby removing the specific route from route cache. The advantage of PRAC route maintenance is that in the case of both primary and backup path being failed, the source does not go for route recovery process again and instead it makes use of the route cache information [21].

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