Δημοσιεύσεις

@article{Chousainov2021,

title = {Multiservice Loss Models for Cloud Radio Access Networks},

author = {I.A. Chousainov and I. Moscholios and P. Sarigiannidis and M. Logothetis},

url = {https://www.researchgate.net/publication/353991171_Multiservice_Loss_Models_for_Cloud_Radio_Access_Networks},

doi = {10.1109/ACCESS.2021.3105946},

year  = {2021},

date = {2021-08-18},

journal = {IEEE Access},

abstract = {In this paper, a cloud radio access network (C-RAN) is considered where the remote radio heads (RRHs) are separated from the baseband units which form a common pool of computational resource units. Depending on their capacity, the RRHs may form one or more clusters. Each RRH accommodates multiservice traffic, i.e., calls from different service-classes with different radio and computational resource requirements. Arriving calls follow a Poisson process and simultaneously require radio and computational resource units in order to be accepted in the serving RRH. If their resource requirements cannot be met then calls are blocked and lost. Otherwise, calls remain in the serving RRH for a generally distributed service time. Assuming the single-cluster C-RAN, we model it as a multiservice loss system, prove that a product form solution exists for the steady-state probabilities and determine call blocking probabilities via an efficient convolution algorithm whose accuracy is validated via simulation. Furthermore, we generalize the previous multiservice loss model by considering the more complex multi-cluster case where RRHs of the same capacity are grouped in different clusters.},

keywords = {call blocking, Cloud-radio access, convolution, poisson process},

pubstate = {published},

tppubtype = {article}

}

@article{Chousainov2021b,

title = {Multiservice loss models in single or multi-cluster c-ran supporting quasi-random traffic},

author = { I.-A. Chousainov and I. Moscholios and P. Sarigiannidis and M. Logothetis},

url = {https://www.researchgate.net/publication/354616239_Multiservice_Loss_Models_in_Single_or_Multi-Cluster_C-RAN_Supporting_Quasi-Random_Traffic},

doi = {10.3390/app11188559},

year  = {2021},

date = {2021-01-01},

journal = {Applied Sciences (Switzerland)},

volume = {11},

number = {18},

abstract = {In this paper, a cloud radio access network (C-RAN) is considered where the baseband units form a pool of computational resource units and are separated from the remote radio heads (RRHs). Based on their radio capacity, the RRHs may form one or many clusters: a single cluster when all RRHs have the same capacity and multi-clusters where RRHs of the same radio capacity are grouped in the same cluster. Each RRH services the so-called multiservice traffic, i.e., calls from many service classes with various radio and computational resource requirements. Calls arrive in the RRHs according to a quasi-random process. This means that new calls are generated by a finite number of mobile users. Arriving calls require simultaneously computational and radio resource units in order to be accepted in the system, i.e., in the serving RRH. If their requirements are met, then these calls are served in the (serving) RRH for a service time which is generally distributed. Otherwise, call blocking occurs. We start with the single-cluster C-RAN and model it as a multiservice loss system, prove that the model has a product form solution, and determine time congestion probabilities via a convolution algorithm whose accuracy is validated with the aid of simulation. Furthermore, the previous model is generalized to include the more complex case of more than one clusters. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.},

note = {cited By 0},

keywords = {Cloud-radio access, Cluster, convolution, Product form, Quasi-random, Time congestion},

pubstate = {published},

tppubtype = {article}

}

@article{Moscholios202051,

title = {Performance evaluation of the threshold call admission policy in multi-rate loss systems},

author = { I.D. Moscholios and I.-A. Chousainov and P.I. Panagoulias and P.G. Sarigiannidis and M.D. Logothetis},

url = {https://www.researchgate.net/publication/342568954_Performance_Evaluation_of_the_Threshold_Call_Admission_Policy_in_Multi-rate_Loss_Systems},

doi = {10.26636/jtit.2020.142120},

year  = {2020},

date = {2020-01-01},

journal = {Journal of Telecommunications and Information Technology},

number = {2},

pages = {51-60},

abstract = {In this paper we consider a link, characterized by specific capacity, that services multi-rate random or quasirandom traffic. Random traffic is generated by an infinite number of traffic sources, while quasi-random traffic is generated by a finite population of traffic sources. The link is modeled as a multi-rate loss system. Handover and new calls are distinguished. New calls compete for the available bandwidth under a threshold call admission policy. In that policy, a new call of a particular service-class is not allowed to enter the system if the in-service handover and new calls of the same service-class plus the new call, exceed a predefined threshold (which can be different for each service-class). On the other hand, handover calls compete for the available bandwidth based on the complete sharing policy. We show that the steady state probabilities in the proposed models have a product form solution (PFS). The PFS leads to a convolution algorithm for accurate calculation of congestion probabilities and link utilization. © 2020 National Institute of Telecommunications. All rights reserved.},

keywords = {blocking, Congestion, convolution, Product form, Quasi-random, Rando},

pubstate = {published},

tppubtype = {article}

}