Page 44 - ITU Journal Future and evolving technologies – Volume 2 (2021), Issue 2

ITU Journal on Future and Evolving Technologies, Volume 2 (2021), Issue 2

nated to initiate content discovery, which decreases colli‑ cache placement algorithms. In the advertisement based
sions and improves of loading. scheme (ABD2D) Help Users (HUs) advertise cached con‑
tent and Ordinary Users (OUs) look for content over a lim‑
6.5 6 ABD2D-BM ited number of dedicated resource blocks (RBs). On the
Number of Beacons for Unit Offloading 4.5 5 4 In both cases, HUs have a clustered structure, which im‑
other hand, in the discovery based scheme (DBD2D), Or‑
ABD2D
dinary Users (OUs) send discovery messages in order to
DBD2D-BM
DBD2D
5.5
express to the HUs their need for content.
proves both cache placement and content delivery. For
both procedures, we make comprehensive simulations
for various performance metrics and against varying pa‑
3.5
rameters. Simulation results show that ABD2D along

tency, and improves of loading performance even for
2.5
compelling circumstances, such as, high user density, less
2 3 with clustered HUs, provides less overhead, reduced la‑
number of dedicated RBs, and high SINR requirement.
-10 -5 0 5 10 15 20
SINR Threshold (dB)
In the scope of this paper, we have assumed that the
Fig. 13 – Mean Number of Beacons for Unit Of loading for Varying SINR content popularity among users is time‑invariant, well
Threshold Value known and not user dependent. In a more realistic sce‑
nario, stationary and totally identical user preferences
are not expected. Therefore, HU‑side time‑varying pop‑
400
ularity and its estimation is planned to be investigated in
future work. Furthermore, the attitude of the proposed
350
procedures against mobility will be examined in detail
ABD2D-BM later on in conjunction with cluster lifetime estimation
Mean Offloading 250 DBD2D riod. Also the proposed model and methods for in‑band
300
ABD2D
and adaptive clustering and cache placement renewal pe‑
DBD2D-BM
DBCA+HCA
MPCC
D2D communication must be applicable to existing and
future technologies. The LTE Direct framework is consid‑
200
ered while deriving a proposed resource allocation model
and access methodology. On the other hand, technical re‑
150
ports and speci ication documents prepared by the 3GPP
that cover 5G proximity services are not available yet. Ac‑
100
-10 -5 0 5 10 15 20 cordingly, adaptation of the network model and proposed
SINR Threshold (dB) methodologies to 5G technology is prioritized for upcom‑
ing research.
Fig. 14 – Mean Of loading for Varying SINR Threshold Value
Lastly, Figs. 13 and 14 present the performance indica‑ REFERENCES
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