An Analytical Model for Multi-Tenant Radio Access Networks Supporting Guaranteed Bit Rate Services

Abstract

Network slicing is a key feature of forthcoming fifth generation (5G) systems to facilitate the partitioning of the network into multiple logical networks customized according to different business and application needs. Network slicing is a fundamental capability for enabling a cost-effective deployment and operation of 5G, as it allows the materialization of multi-tenant networks in which the same infrastructure is shared among multiple communication providers, each one using a different slice. This paper proposes a Markovian approach to characterize the resource sharing in multi-tenant scenarios with diverse guaranteed bit rate services by considering a slice-aware admission control policy. After describing the Markov model and its implementation and discussing its suitability, the model is applied to study the performance attained in a scenario with two different slices, one for enhanced mobile broadband communications and the other for mission critical services. The system is analyzed under standard and disaster situations, thus illustrating the capability to properly manage the different multi-tenant and multi-service traffic loads. INDEX TERMS Admission control, Markov processes, mobile communication, multi-tenancy, radio access networks, RAN slicing.

An Analytical Model for 5G Network Resource Sharing with Flexible SLA-Oriented Slice Isolation

“…For the most part, this category revolves around RAN and radio spectrum (channel) resources, since the latter inherently cannot be easily scaled up. However, the ways to consider and slice RAN resources vary-while many studies address the slicing of the radio resources of a single base station [8][9][10][11][12][13][14][15][16][17], others consider a combination of specific RAN-related resources, namely the base station's radio channel capacity, cache and backhaul bandwidth [18], a cluster of several homogeneous [19][20][21] or heterogeneous [22][23][24] base stations, or the capacity of a Cloud-RAN (C-RAN), in which the baseband resources of several homogeneous [25,26] or heterogeneous [27,28] radio systems are centralized into a single resource pool. Besides, some studies deal with finite sets of purely abstract [29,30] or more specific-radio, transport and computing [31]-network resources.…”

“…In Reference [32], slices are assumed to carry either elastic or inelastic traffics. References [17,18] consider a set of slices, each providing a finite number of services with certain characteristics. Finally, many studies consider a set of slices without specifying the nature of the carried traffic [9,12,14,[19][20][21][22]25,29]; in this case, the scenario of MVNOs is sometimes exploited, although from a broader perspective than that of the one currently deployed.…”

“…Some works adopt auction models, where resource allocation follows the tenants' bids for their slices [14] or for their slice users [20,21]. Some works [16,17] specifically consider slice isolation, which is provided by setting a fixed upper limit on the slice's capacity. Slice isolation via guaranteed minima is proposed in References [8,9,19,29].…”

“…Slice isolation via guaranteed minima is proposed in References [8,9,19,29]. Finally, some authors, namely References [15,17,27], take into account slice priorities.…”

“…In the literature, the majority of studies, except for the most technology-specific ones, assume each of the considered resources to be homogeneous and divisible, and propose an algorithm for determining slices' sizes (capacities) as shares of the resources' capacities [9,[12][13][14][15]18,20,21,29,30]. If the services provided in the slice to end users require a certain minimum data rate, such as Guaranteed Bit Rate (GBR) services, the slicing policy may include not only resource allocation but also admission control [17,21,23,27]. Network slicing at the admission-control level is discussed in Reference [33] along with other approaches to RAN slicing, while user blocking probabilities for such systems are estimated in References [17,21].…”