Abstract
Internet of Things integrates various technologies, including wireless sensor networks, edge computing, and cloud computing, to support a wide range of applications such as environmental monitoring and disaster surveillance. In these types of applications, IoT devices operate using limited resources in terms of battery, communication bandwidth, processing, and memory capacities. In this context, load balancing, fault tolerance, and energy and memory efficiency are among the most important issues related to data dissemination in IoT networks. In order to successfully cope with the abovementioned issues, two main approaches—data-centric storage and distributed data storage—have been proposed in the literature. Both approaches suffer from data loss due to memory and/or energy depletion in the storage nodes. Even though several techniques have been proposed so far to overcome the abovementioned problems, the proposed solutions typically focus on one issue at a time. In this article, we propose a cross-layer optimization approach to increase memory and energy efficiency as well as support load balancing. The optimization problem is a mixed-integer nonlinear programming problem, and we solve it using a genetic algorithm. Moreover, we integrate the data-centric storage features into distributed data storage mechanisms and present a novel heuristic approach, denoted as Collaborative Memory and Energy Management, to solve the underlying optimization problem. We also propose analytical and simulation frameworks for performance evaluation. Our results show that the proposed method outperforms the existing approaches in various IoT scenarios.
In this article
Where should a network keep a second copy?
A sensor network can lose information when a storage node runs out of battery or memory. Collaborative Memory and Energy Management (CoMEM) coordinates monitor and storage-node selection using both resources, combining data-centric retrieval with distributed storage.
Choosing storage nodes for energy alone can overlook memory exhaustion; choosing for memory alone can drain batteries. A practical data-dissemination method needs to account for both while balancing load.
From the question to the evidence
Treat memory and energy together
A storage node may lose information because it runs out of memory, energy, or reachable neighbors. The paper models the WSN as a directed graph and combines memory use, energy consumption and a resource-dependent load-balancing factor in a cross-layer objective. It includes sensing, forwarding, querying, link capacity and flow-conservation constraints.
2020 CoMEM article, PDF pp. 4-7, network model, Eqs. (1)-(22) and constraints C1-C17. Read source · PDF page 4 ↗
Establish zones and initial roles
Partition the sensing region into zones and use geographic hashing to choose an initial monitor and storage nodes. The reported setup assumes stationary targets and a fixed zone count. Monitors provide known destinations for storage and queries, while storage nodes retain detailed event records.
2020 CoMEM article, PDF pp. 7-8, DCS storage model and the CoMEM initialization description. Read source · PDF page 7 ↗
Share resource information
Nodes report normalized memory and energy information to their zone monitor, either along with sensed data or through dedicated packets. The monitor maintains a performance table and computes an election metric using both resources. A variation test triggers re-election instead of restricting replica selection to the current storage node's immediate neighbors.
2020 CoMEM article, PDF p. 8, performance table and Eqs. (23)-(25). Read source · PDF page 8 ↗
Re-elect storage nodes across the zone
The election procedure compares candidates using energy and memory coefficients. It builds coverage counts, excludes candidates covered by a stronger candidate in both dimensions, and selects a candidate with the highest coverage count. Figure 4 resolves ties by the energy coefficient and then the memory coefficient. This is a heuristic selection rule, not a proof of global optimality.
2020 CoMEM article, PDF pp. 8-9, replica election discussion and Fig. 4. Read source · PDF page 8 ↗
Rotate the monitor when needed
Storage nodes receive the zone's residual-energy information and evaluate the monitor's energy gap. When the paper's threshold test is met, the storage node announces a new monitor with the highest reported residual energy. The outgoing monitor transfers its records to the replacement. This addresses the resource cost of concentrating coordination traffic at one monitor.
2020 CoMEM article, PDF p. 9, monitor-election mechanism and Eq. (26). Read source · PDF page 9 ↗
Compare the full trade-off
Evaluate CoMEM against DCS, R-DCS and LCDDR using energy consumption, the combined objective, delay, data loss, computational work and scalability. The optimization problem is solved with a genetic algorithm to provide the study's optimization-based comparison. CoMEM leads on several resource measures, while basic DCS has lower delay and less computational work in the reported ranking.
2020 CoMEM article, PDF pp. 11-15, performance evaluation, Figs. 6-11, Table 3 and conclusions. Read source · PDF page 11 ↗
Architecture and compact method notes
Architecture & information flow
CoMEM uses the wireless sensor network portion of an IoT system with gateways, edge resources and cloud storage. Its contribution concerns storage and retrieval within the WSN. Each zone contains sensor nodes, a monitor and event-specific storage nodes. The monitor maintains summaries and resource reports, while storage nodes retain detailed records and participate in selecting a replacement monitor. Initial geographic hashing gives way to resource-driven role election. The study uses RPL to route traffic to monitors and storage destinations, with hop-count or expected-transmission-count objectives discussed in the simulator description.
2020 CoMEM article, PDF pp. 4 and 7-10, Fig. 1, CoMEM method and network-engine description. This architecture explanation comes from the published article, not the research presentation. Read source · PDF page 4 ↗
- Model the joint costFormulate a cross-layer mixed-integer nonlinear optimization problem that combines energy, memory use, and load balancing.
- Coordinate within zonesUse monitor nodes to organize storage and queries, retaining summaries while routing detailed records to selected storage nodes.
- Adapt roles and replicasElect monitor and storage nodes using the availability of both energy and memory, replicating data as resources become constrained.
- Evaluate the trade-offCompare the distributed CoMEM heuristic against related storage methods and an optimization-based benchmark.
What the study reports
The principal evaluation models static nodes in an IEEE 802.15.4/6LoWPAN network, with 30 nodes in a 12 m by 12 m area and one to ten targets. Mobility and other wireless technologies are outside the evaluated scope.
These are results reported by the source publication, not an independent reproduction. Conditions and source disagreements are retained beside the evidence they affect.
Ranks are reproduced from Table 3, which summarizes the article's comparative evaluation at the largest target count, ten. The scalability experiment also varies the number of deployed devices. A smaller rank is better, and equal ranks indicate similar reported performance.
| Performance indicator | DCS | R-DCS | CoMEM | LCDDR |
|---|---|---|---|---|
| Energy consumption | 3 | 1 | 1 | 2 |
| Combined objective | 3 | 2 | 1 | 4 |
| Delay | 1 | 2 | 3 | 4 |
| Data loss | 3 | 2 | 1 | 1 |
| Computational complexity | 1 | 2 | 2 | 3 |
| Scalability | 2 | 1 | 1 | 3 |
2020 CoMEM article, PDF pp. 14-15, Table 3 and its explanatory text; Figs. 6-11. Read source · PDF page 14 ↗
These are ordinal rankings, not improvement percentages or measurements in physical units. CoMEM is first or tied first on four indicators, but ranks third for delay and tied second for computational complexity.
The scenario assumes a stable radio range, static sensors and nodes that do not crash simply because of a traffic burst. These are study parameters rather than universal deployment defaults.
| Setting | Reported value or procedure |
|---|---|
| Sensing region | 12 x 12 m |
| Sensor nodes | 30 static nodes in the main evaluation |
| Target count | 1-10 stationary targets |
| Minimum node separation | 1.4 m |
| Wireless setting | IEEE 802.15.4 / 6LoWPAN, 2.4 GHz |
| Packet size / sample size | 127 bytes / 26 bytes |
| Sampling / query rate | 0.5 samples per second / 0.1 queries per second |
| Simulation duration | 80 seconds |
| Optimization comparison | The paper formulates an MINLP and reports solving it with a genetic algorithm |
2020 CoMEM article, PDF p. 11, Table 2 and evaluation assumptions; PDF p. 12, workload description; PDF p. 15, conclusions. Read source · PDF page 11 ↗
The optimization-based comparison is reported by the paper. A genetic-algorithm solution is not, by itself, a certificate of the global optimum.
Additional reported observations
- For the reported ten-target comparison, CoMEM ranks first (including ties) for energy consumption, the combined objective, data loss, and scalability.
2020 paper, PDF pp. 14-15, Table 3 and discussion. Read source · PDF page 14 ↗
- Those gains come with higher delay than basic DCS and greater computational work; the paper reports a trade-off rather than dominance on every metric.
2020 paper, PDF pp. 13-15, Figs. 8, 10 and Table 3. Read source · PDF page 13 ↗
Scope & limitations
- The evaluation assumes static nodes and relatively stable radio conditions.
- Extra coordination raises delay compared with basic data-centric storage.
- The reported comparisons depend on the study traffic, energy, memory, and physical-layer models; no universal percentage improvement is claimed.
Cited in context
Background citation in the introduction
A novel Hadamard matrix based hybrid compressive sensing technique for enhancing energy efficiency and network longevity
The compressive-sensing paper cites Hejazi and Ferrari in the opening sentence of its introduction, as a reference for WSN-based IoT systems that gather network data and periodically send it to a central base station.
The citation supports general background on sensor-network-based IoT. The citing paper does not describe, adapt or evaluate the data-loss-prevention method, and the citation does not establish a collaboration or endorsement.
Inspect reference [1] →Grouped related-work citation of the 2018 preprint
An Energy-Aware, Highly Available, and Fault-Tolerant Method for Reliable IoT Systems
The IoT reliability paper cites Hejazi and Ferrari within a group of four references ([7]–[10]) on sensor-network applications for monitoring and prevention, at the start of its related-work section. Its reference entry gives the title of Hejazi and Ferrari’s July 2018 preprint, “Energy and Memory Efficient Data Loss Prevention in Wireless Sensor Networks”, with the venue Sensors, 2018.
The reference matches the title and authors of the 2018 Preprints.org preprint (doi: 10.20944/preprints201807.0206.v1), not the title or venue of this 2020 article. The preprint addresses the same subject; this site does not establish whether it is an earlier version of the 2020 article, and no Sensors publication with this title was found. The grouped mention does not describe, reuse or evaluate the method, and does not establish a collaboration or endorsement.
Inspect reference [10] →Method outline
Conceptual pseudocode paraphrased from the CoMEM description and Figure 4. It is not the published implementation or a directly executable algorithm. Resource normalization and threshold tests remain as defined in the paper; the source's resource-coefficient notation requires care when implementing.
Conceptual CoMEM storage and role election · pseudocode
INPUT zone membership, event records and node memory/energy reports
INITIALIZE a monitor and storage nodes in each zone using geographic hashing
ON sensed data, SEND the record to the zone monitor
KEEP the summary at the monitor and FORWARD details to the assigned storage node
UPDATE the monitor's table with normalized resource reports from zone members
COMPUTE the joint election metric and its variation test from Eqs. (23)-(25)
WHEN the storage re-election condition holds:
INITIALIZE each candidate's coverage count to one
COMPARE each candidate with active candidates in its zone
IF another candidate has larger energy and memory coefficients:
MARK the weaker candidate covered and INCREMENT the stronger candidate's count
SELECT the highest coverage count, then energy coefficient, then memory coefficient
USE the elected candidate for the storage/replica role
PERIODICALLY SHARE residual-energy information with the storage node
WHEN the monitor energy-gap test in Eq. (26) exceeds its threshold:
ANNOUNCE the highest-residual-energy candidate as the new monitor
TRANSFER the outgoing monitor's records to the new monitor
ON a query, LET the monitor answer from its summary or contact the relevant storage node
EVALUATE resource use, delay and data loss together across the study scenarios2020 CoMEM article, PDF pp. 8-9, CoMEM storage model, Eqs. (23)-(26) and Fig. 4. Read source · PDF page 8 ↗
Presentation guide and further interpretation
Start with two ways data can become unavailable
Explain that an energy-rich node can have little free memory, while a node with free memory can have a nearly depleted battery. The joint resource objective makes this trade-off explicit before introducing the monitor and storage roles.
2020 CoMEM article, PDF pp. 4-6, motivation, resource definitions and Eq. (4). Read source · PDF page 4 ↗
Separate data storage from coordination
Follow one event record to the monitor: a summary remains there and details go to a storage node. Then follow a query through the same organization. This explains both the efficient lookup path and the extra coordination cost.
2020 CoMEM article, PDF pp. 7-8, DCS and zone-monitor storage/retrieval description. Read source · PDF page 7 ↗
Show why both roles must change
Replica election considers the resources of nodes throughout the zone, rather than only nearby nodes. Monitor election is a separate energy-based process coordinated by storage nodes. Changing only storage nodes would leave the monitor carrying a continuing traffic burden.
2020 CoMEM article, PDF pp. 8-9, Fig. 4 and monitor-election discussion. Read source · PDF page 8 ↗
Read the ranking as a trade-off
Present all six indicators together. CoMEM's resource and data-loss ranks accompany a delay cost and additional computation. Explain that rank one is a relative outcome for the evaluated configurations, not a universal gain or a guarantee of zero lost data.
2020 CoMEM article, PDF pp. 13-15, Figs. 8-11 and Table 3. Read source · PDF page 13 ↗
Further interpretation notes
- The main evaluation uses static sensor nodes and stationary targets. It does not establish performance for arbitrary mobility or rapidly changing channels.
- CoMEM is a heuristic for the cross-layer resource problem. The article's genetic-algorithm comparison should not be described as a proven global optimum without a separate optimality certificate.
- The paper uses normalized energy/memory coefficients in replica election and residual energy in monitor election. Its notation mixes availability and consumption language, so the conceptual roadmap avoids inventing an implementation-level normalization rule.
- The published Table 3 rankings are preserved directly. No numerical energy saving, memory saving, loss rate or delay has been estimated from the figures.
- Additional coordination improves several resource measures while increasing delay relative to basic DCS. No blanket claim of superiority on every metric is supported by the ranking table.
- The paper discusses detecting unauthorized nodes through monitor information, but this presentation does not claim that CoMEM supplies a formally validated security mechanism.
- The article's receive-energy prose and Table 2 differ, so a receive-energy value is intentionally excluded from the scenario table.
- This roadmap is grounded in the 2020 published article. The supplied doctoral presentation focuses on the later 6G studies and is not a source for these CoMEM details.
Cite this article
Pooya Hejazi; Gianluigi Ferrari. (2020). A novel approach for energy- and memory-efficient data loss prevention to support Internet of Things networks. International Journal of Distributed Sensor Networks, 16(6). https://doi.org/10.1177/1550147720929823
BibTeX
@article{Hejazi2020IotDataLoss,
title = {A novel approach for energy- and memory-efficient data loss prevention to support Internet of Things networks},
author = {Hejazi, Pooya and Ferrari, Gianluigi},
journal = {International Journal of Distributed Sensor Networks},
year = {2020},
volume = {16},
number = {6},
doi = {10.1177/1550147720929823},
url = {https://doi.org/10.1177/1550147720929823}
}Download BibTeX · Download RIS
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