Page 166 - ITU Journal, Future and evolving technologies - Volume 1 (2020), Issue 1, Inaugural issue

ITU Journal on Future and Evolving Technologies, Volume 1 (2020), Issue 1

it can be broadly classified into two groups based on categories:
whether the resource management is driven by pric-
ing ([7, 8, 17, 31, 42, 58, 59, 76, 136, 146, 154, 155]) or not 1. partitioning and allocation of resources shared by
([50,62,63,68,73,79,97,123,130,132,133,138,151]). For multiple operators,
instance, Ho et al. in [58] consider the case when there 2. the literature on Wireless Network Virtualization
is a single InP serving multiple MVNOs, each charac- that mostly deals with the sharing of resources
terized by a fixed number of users and a Service Level between a single InP and multiple SPs; this sub-
Agreement (SLA) given in terms of a minimum resource category, can be further subdivided into:
requirement and a maximum aggregate rate (over all its
users). The InP has to decide how to price and allo- (a) articles that base their modelling on pricing
cate its available BS resources among all users of all issues and
MVNOs so as to maximize its profit while guaranteeing (b) articles that base their modelling on other is-
the SLA of each MVNO. In this work MVNOs are also sues, such as performance metrics, and
self-interested as the goal of each MVNO is to maximize
its own profit given by the difference between the total 3. a large body of 5G literature that deals with re-
rate obtained from resources allocated by the InP and source management and network slicing.
their cost. The problem is then modeled as a one-leader
multi-follower variant of the Stackelberg game with the 3.3 Enablers and architectures
InP being the leader and each MVNO being a follower.
Instead, Kamel et al. in [73] address a scheduling prob- Although the different alternatives for infrastructure
lem over one time frame which is modeled through math- and spectrum sharing can be financially attractive for
ematical programming. In details, there is a single InP MNOs, they where not always supported by the 3GPP
and a set of VOs, each having a fixed number of users specifications; in fact, while a basic type of network shar-
and a minimum resource requirement (total Physical ing was supported as of Release 5, there was no sup-
Resource Blocks (PRBs) over the time frame). The InP port for more involved network sharing scenarios for the
4
has to decide to which user to assign each PRB and the 3GPP GSM EDGE RAN (GERAN) prior to Release
amount of power to allocate to each PRB so as to max- 10 ([3]).
imize the total rate over the time frame while satisfying
the maximum power constraint, the minimum resource Standardization apart, the research community has
requirement of each VO and a VO-specific proportional largely contributed on the topics of enabling network
fairness constraint for cell-center and cell-edge users. sharing, e.g., through novel architectures. While passive
sharing (i.e., site/tower sharing) is the simplest network
In 5G, the problem of resource management reemerges sharing alternative to implement, the different types of
in the context of multi-tenancy and its enabler, network active sharing demand architectural changes in mobile
slicing ([5, 6]). Tenants (such as MVNOs, Over The networks e.g., to guarantee the isolation of the involved
Top (OTT) providers and vertical industries) have dis- MNOs in terms of their private information in order to
tinct requirements to support their services which have avoid harming competition, or they demand changes at
to be translated into appropriate network resources. It the protocol stack level to implement the novel resource
is worth noting that network slicing does not involve management algorithms etc. According to [64], radio re-
only the RAN segment but it can be end-to-end. How- source management should be delegated to a third party
ever, the problem of resource management at the RAN provider to ensure isolation and therefore not to inter-
segment has brought about a significant amount of at- fere with competition. In [56] the authors introduce
tention from the research community due to the intrin- AppRAN which relies on a centralized scheduler to per-
sically complex nature of the radio (wireless) access. form application-level resource allocation for a shared
For instance, the authors in [125] propose the “5G Net- RAN.
work Slice Broker”, a centralized scheduler based on the In particular, different flavors of virtualization have been
3 rd Generation Partnership Project (3GPP) specifica- widely considered by the research community as candi-
tions for network sharing. The proposed scheduler has date enablers for network sharing. For instance, the
a global view of the shared network and applies admis- virtualized network architecture proposed in [60] can
sion control and resource allocation, translating the ten- support network sharing. Other papers that resort to
ants’ request, with given SLAs, into available network virtualization are e.g., [10, 34, 72, 117, 152]. In particu-
resources. Other examples on resource management at lar, the authors of [38] and of [43] propose the “Network
the RAN in the context of multi-tenancy/network slic- without Borders”, namely the virtualized pool of (het-
ing are given in [9,44,47,122,144,148,153]. erogeneous) wireless resources for which infrastructure
and spectrum pooling are essential. Costanzo et al. in
Summarizing, the Resource Management category is [37] suggest an architecture for 4G RAN sharing based
a very rich part of the infrastructure sharing litera- on SDN and NFV.
ture. Within this category, we have identified three sub- 4 Enhanced Data rates for GSM Evolution

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