• Bankapalli Goutham
• Prof. Kuda Nageswara Rao

Provisioning of Quality of Service (QoS) is a key issue in any multi-media system. However, in wireless systems, supporting QoS requirements of different traffic types is more challenging due to the need to minimize two performance metrics - the probability of dropping a handover call and the probability of blocking a new call. Since QoS requirements are not as stringent for non-real-time traffic types, as opposed to real-time traffic, more calls can be accommodated by releasing some bandwidth from the already admitted non-real-time traffic calls. Long Term Evolution (LTE) network standard defines requirements to guarantee Quality of Service (QoS) for diverse applications such as VoIP, video and web browsing according to the Third Generation Partnership Project (3GPP) specifications. The Radio Resource Management (RRM) techniques such as Call Admission Control Schemes play an important role in providing such guarantees. Consequently, several schemes have been proposed to manage resources while ensuring QoS to wireless applications. This paper presents a survey of Call Admission Control (CAC) Schemes. These algorithms are classified into CAC with Pre-emption, Resource Reservation (RR), Resource Degradation (RD), Delay Awareness (DA) or Channel Awareness (CA). The operational procedure, strengths and weaknesses of each scheme are discussed. If we require that such a released bandwidth to accept a handover call ought to be larger than the bandwidth to accept a new call, then the resulting probability of dropping a handover call will be smaller than the probability of blocking a new call. In this paper we propose an efficient Call Admission Control (CAC) that relies on adaptive multi-level bandwidth-allocation scheme for non-real-time calls. The scheme allows reduction of the call dropping probability along with increase of the bandwidth utilization. The numerical results show that the proposed scheme is capable of attaining negligible handover call dropping probability without sacrificing bandwidth utilization. In addition, we proposed reservation and degradation approach to admit many users when there is a limited number of bandwidth, which also achieved effective utilization of network resources. Simulation results show that the proposed scheme significantly outperforms the reservation-based scheme and bandwidth degradation schemes in terms of admitting many calls and guaranteeing QoS to all the traffic types in the network. Numerical results imitate to experimental results with in significant differences..

Adaptive bandwidth allocation, Quality of Service, multi-class services, multi-class traffic, call dropping probability, call blocking probability, call admission control, CAC, LTE Networks, Call Admission Control, Radio Resource Management

"A implementation of call switching over volte networks using dynamic initiation of voice request", International Journal of Emerging Technologies and Innovative Research (www.jetir.org), ISSN:2349-5162, Vol.5, Issue 12, page no.292-301, December-2018, Available :http://www.jetir.org/papers/JETIR1812344.pdf

"A implementation of call switching over volte networks using dynamic initiation of voice request", International Journal of Emerging Technologies and Innovative Research (www.jetir.org | UGC and issn Approved), ISSN:2349-5162, Vol.5, Issue 12, page no. pp292-301, December-2018, Available at : http://www.jetir.org/papers/JETIR1812344.pdf