Enhancing Scalability in Wi-Fi IoT Networks with Logical Data Plane
Segregation Using SDN Principles
Gabriel Vieira
a
, Ana Rita Ortigoso
b
, Daniel Fuentes
c
, Luis Fraz
˜
ao
d
, Nuno Costa
e
and
Ant
´
onio Pereira
f
Computer Science and Communication Research Centre, Polytechnic University of Leiria, Portugal
{gabriel.m.vieira, ana.l.ortigoso, daniel.fuentes, luis.frazao, nuno.costa, apereira}@ipleiria.pt
Keywords:
Data Plane Segregation, IoT, Wi-Fi 6, ESP-NOW, SDN, Scalability.
Abstract:
The increasing demand for wireless connectivity, with IoT devices projected to exceed 20 billion by 2025,
reinforces Wi-Fi as the dominant technology. However, the standard star topology limits coverage for widely
dispersed IoT devices. While mesh networking extends coverage, most IoT endpoints lack native mesh sup-
port, posing scalability and security challenges. This study proposes an IoT architecture leveraging a dual-
stack and dual logical data plane approach based on SDN principles. It separates control and data traffic into
three planes: IoT data, Wi-Fi extension, and control. The control plane employs ESP-NOW for mesh optimisa-
tion, while Wi-Fi ensures compatibility and expanded functionality. A prototype using ESP32-C6 DevKitC-1
modules demonstrates cost-efficiency, supporting stable connectivity with performance degradation beyond
50 metres. Experimental results confirm the architecture’s ability to establish a self-organising, resilient mesh
network with dynamic reconfiguration, offering a scalable and flexible solution for IoT mesh networks.
1 INTRODUCTION
Wi-Fi technology is evolving rapidly, driven by the
increasing societal demand for wireless connectiv-
ity. It has become the preferred choice for Internet
of Things (IoT) devices, with the number of con-
nected devices worldwide expected to surpass 20 bil-
lion by 2025 (Analytics, 2024). Several initiatives
have been implemented to establish heterogeneous
networks that enable communication between differ-
ent devices (Zegeye et al., 2023). However, the in-
creasing demand for enhanced security and efficient
device configuration highlights the limitations of a
single data plane, particularly in terms of scalabil-
ity and vulnerability to security threats. As a result,
the use of multiple planes to forward data can help
mitigate (Kaljic et al., 2019). Providing Wi-Fi cover-
age for IoT devices, which are often widely dispersed,
presents significant challenges. This is especially rel-
evant in environments and smart buildings such as ho-
a
https://orcid.org/0009-0000-2300-8441
b
https://orcid.org/0009-0001-7529-5857
c
https://orcid.org/0000-0001-9726-1087
d
https://orcid.org/0000-0003-2571-7940
e
https://orcid.org/0000-0002-2353-369X
f
https://orcid.org/0000-0001-5062-1241
tels, corporate offices, factories, hospitals, and univer-
sity campuses. (Khanna and Kaur, 2020). A solution
that involves extending the Wi-Fi network by lever-
aging existing IoT devices through a mesh network,
as there are already numerous devices available (e.g.,
microwaves, refrigerators, sensors, and other actua-
tors) is favourable. Ideally, this could be achieved by
simply updating the firmware of compatible devices,
enabling networks to become more configurable and
extend their coverage area.
This research aims to provide a solution that en-
hances current IoT devices with dual logical data
planes with the capability to create an IoT Wi-Fi mesh
network using the latest fully specified Wi-Fi protocol
(Ferro and Potorti, 2005), the Wi-Fi 6 / 802.11ax (Is-
lam and Kashem, 2022), and the low-level communi-
cation protocol ESP-NOW, which facilitates manag-
ing IoT devices and their mesh network. The solution
makes the following contributions:
Development of a Dual Data Plane Architec-
ture: Conceptualised an architecture that makes
the use of two logical data planes possible, for IoT
devices and for Wi-Fi end devices users.
Development of a Dual Stack Single Radio
Mesh Architecture: Designed an architecture
that integrates two different communication pro-
378
Vieira, G., Ortigoso, A. R., Fuentes, D., Frazão, L., Costa, N. and Pereira, A.
Enhancing Scalability in Wi-Fi IoT Networks with Logical Data Plane Segregation Using SDN Principles.
DOI: 10.5220/0013428800003944
Paper published under CC license (CC BY-NC-ND 4.0)
In Proceedings of the 10th International Conference on Internet of Things, Big Data and Security (IoTBDS 2025), pages 378-385
ISBN: 978-989-758-750-4; ISSN: 2184-4976
Proceedings Copyright © 2025 by SCITEPRESS Science and Technology Publications, Lda.
tocols (Wi-Fi 6 & ESP-NOW), to provide both
data segregation and extend coverage by using
other IoT devices as part of the network.
Logical Separation of Data and Control
Planes: The architecture proposed introduces a
separation between control and two logical data
planes. This introduces an Software-Defined Net-
working (SDN) inspired virtual separation that al-
lows independent management of data, reducing
interference and enhancing security.
Cost-Effective Prototype Implementation: De-
velopment of a functional mesh network proto-
type using low-cost IoT devices that implement
the Wi-Fi 6 and ESP-NOW protocols concur-
rently.
Comprehensive Functional and Performance
Evaluation: Testing the feasibility of the solu-
tion and the prototype to evaluate feasibility, func-
tional integrity, and performance metrics.
The article is structured as follows: section 2 pro-
vides an overview of the technologies employed and
their alternatives. Section 3 offers a literature review,
placing this research in the context of similar solu-
tions and prior work. Section 4 describes the pro-
posed architecture, integrating existing IoT devices
into the Wi-Fi infrastructure to provide network ac-
cess to nearby end-user devices. In Section 5, the im-
plemented prototype is presented with details on hard-
ware components, testing setup, control plane and
data plane. Section 6 outlines the results obtained
from the prototype, which are further analysed and
discussed in section 7 to provide insights into the so-
lution’s performance and functionality. Finally, sec-
tion 8 concludes the research by summarising key
findings and highlighting potential future work.
2 BACKGROUND
Wi-Fi is the most widely used wireless system, known
for its low cost, ease of installation and use, and mini-
mal skill requirements. The latest standard for IoT de-
vices, Wi-Fi 6 (802.11ax), is increasingly adopted in
industrial and IoT markets due to its high throughput,
low latency, precise localisation capabilities, efficient
resource management through Resource Units (RUs),
support for speeds up to 9.6 Gbps, and tri-band oper-
ation (2.4, 5, and 6 GHz) (Karamyshev et al., 2024).
These recent advancements enable its use in battery-
powered IoT devices, solidifying its role as one of the
preferred choices for connecting both IoT and user
devices (Oughton et al., 2021) (Mozaffariahrar et al.,
2022b) (Perez-Ramirez et al., 2022).
ESP-NOW is a protocol designed to deliver low
latency, low power consumption, and long-distance
communication on the 2.4 GHz spectrum (Eridani
et al., 2021). The ESP-NOW protocol can transmit up
to 250 bytes of data and can coexist with both Wi-Fi
and Bluetooth (Espressif, 2023d) (Espressif, 2023c).
While the 250-byte payload may seem restrictive, it
is sufficient for many IoT use cases, such as sending
sensor readings or control data. The following tables
1 and 2, detail the structure of ESP-NOW frame.
Table 1: ESP-NOW frame.
MAC
Header
24 bytes
Category
Code
1 byte
Organisation
ID
3 bytes
Random
4 bytes
Vendor
Specific
7-257 bytes
FCS
4 bytes
Table 2: ESP-NOW vendor specific packet.
Element
ID
Length Organisation
ID
3 bytes
Type Version Body
1 byte 1 byte 1 byte 1 byte 0-250 bytes
Bluetooth is a Personal Area Network (PAN)
that operates within the 2.4 GHz spectrum using fre-
quency hopping to transmit data. There are two ver-
sions of this technology, Classic and Bluetooth Low
Energy (BLE) (Bisdikian, 2001). However, when us-
ing a dual-stack technology, BLE must share antenna
time, which results in reduced performance. (Espres-
sif, 2020b).
Thread is an Internet Protocol (IP) solution using
the IPv6 on the standard IEEE 802.15.4. Thread aims
for reliable, flexible, low-power, device-to-device, ag-
nostic communication, and a self-configuring net-
work that enhances functionality and reduces main-
tenance costs (Thread Group, 2020) (Thread Group,
2024). According to the scope of the work and to au-
thors in (Espressif, 2023f), concurrency with the other
mentioned protocols will not work.
ZigBee, based on IEEE 802.15.4, provides a low
data rate and simple connectivity, designed for low-
powered (battery-operated) devices. ZigBee supports
standard mesh networking, enhancing range and reli-
ability (ZigBee Alliance, 2017). However, it operates
on the same 2.4 GHz band as Wi-Fi, risking interfer-
ence. Its dual PHY adds complexity but offers limited
performance gains. In contrast, Wi-Fi, particularly
Wi-Fi 6, provides higher throughput, lower latency,
and better scalability for modern IoT networks, es-
pecially when leveraging SDN principles for logical
data segregation (Zigbee2MQTT, 2024).
In summary, Wi-Fi offers robust interconnectiv-
ity and performance, while ESP-NOW supports ex-
Enhancing Scalability in Wi-Fi IoT Networks with Logical Data Plane Segregation Using SDN Principles
379
tended ranges with minimal latency. Bluetooth has a
low power consumption, making it an optimal choice
for long-term applications across a range of devices.
ZigBee targets low-powered devices and has a built-
in mesh topology. Among these technologies, ESP-
NOW is noted for its low interference, better energy
efficiency, and lowest latency (Eridani et al., 2021).
A comparative analysis was conducted to iden-
tify low-cost IoT devices that support communica-
tion technologies like Wi-Fi 6, ESP-NOW, Bluetooth,
Thread, and ZigBee. The results highlight the com-
munication capabilities and average prices of the se-
lected devices, as presented in table 3.
Looking at the comparison in table 3 with device
features and prices in conjunction of the aforemen-
tioned, we conclude that for the required, ESP32-C6
meets the desired criteria: Wi-Fi 6 and ESP-NOW
support at a low cost. This device is a new addi-
tion to Espressifs product line, featuring support for
Wi-Fi 6, BLE, Thread, and ZigBee. Additionally,
it integrates the Espressif IoT Development Frame-
work (ESP-IDF), an open-source project based on the
FreeRTOS kernel, offering well-documented drivers,
protocol support, and storage solutions that simplify
IoT development (FreeRTOS, 2024).
3 LITERATURE REVIEW
The scientific community has yet to extensively ex-
plore the integration of complementary communica-
tion protocols in resource-constrained environments.
Current research lacks comprehensive investigations
into their combined application for achieving scala-
bility, energy efficiency, and cost-effectiveness, high-
lighting a significant gap in the field. To the best of
our knowledge, this is one of the few prototypes in
this area.
In the study by (Muhendra et al., 2017), the Quick
Mesh Project (QMP) framework was used to de-
velop a WiFi mesh network with TP-LINK MR3020
routers, configured with the Quick Mesh Project
(QMP) based OpenWRT and BMX6 routing proto-
col. The network utilised the MQTT protocol for
machine-to-machine communication via a publish-
and-subscribe model. An IoT WiFi Client, based on
the low-power ESP8266 module, was also developed
to connect electronic devices such as sensors and ac-
tuators to the network. In contrast to this, the present
solution proposes using devices as network propaga-
tors with multiple planes, eliminating the need for
dedicated mesh routers and creating its own managed
mesh network.
Furthermore, the article by (Gergeleit, 2019) im-
plements a mesh network using the painlessMesh li-
brary, relying on NAT for external network access but
without incorporating a routing protocol. In a simi-
lar vein, Autotree utilises NAT alongside a distance
vector-like routing mechanism tailored for ESP8266
modules, forming a dynamic tree topology with lim-
ited node mobility and simplified deployment. How-
ever, it lacks inter-node IP connectivity. By contrast,
our solution introduces a dual-stack architecture with
logical data plane segregation based on SDN princi-
ples. By isolating control and data traffic using ESP-
NOW and Wi-Fi 6, the system improves scalability
and route management. Moreover, it employs ESP32-
C6 modules to support contemporary protocols, such
as Wi-Fi 6, while enabling self-organising mesh net-
works.
In a related approach, the study by (Manvi and
Maakar, 2020) develops a wireless mesh network with
ESP-32 nodes, allowing decentralised communica-
tion without requiring internet access or routers. Data
is exchanged through TCP servers on port 5555, and
the network exhibits self-healing capabilities when
routes fail. Our work differs by enhancing compat-
ibility and implementing SDN principles to segregate
control and data planes. Through the use of ESP-
NOW and Wi-Fi 6, it achieves optimised traffic flow
and more efficient resource utilisation, thereby sur-
passing the basic peer-to-peer methodology adopted
in (Manvi and Maakar, 2020).
The work of (Khanchuea and Siripokarpirom,
2019) explores the integration of ZigBee, ESP-NOW,
and ModBus protocols within a multi-protocol gate-
way to control IoT devices. ESP-NOW serves as
the foundation for a low-power, multi-hop wireless
network, while ZigBee forms subnetworks for de-
vice communication. Field trials highlight the ef-
fectiveness of ESP32 Wi-Fi/BLE chips combined
with ESP-NOW in constructing energy-efficient, self-
organising sensor networks. In contrast, our solu-
tion focuses on logical data plane segregation using
SDN principles. By leveraging different protocols for
each distinct planes, the system ensures more effi-
cient traffic integration, moving beyond the modular,
multi-protocol approach presented in (Khanchuea and
Siripokarpirom, 2019).
Lastly, Espressif provides the ESP-WIFI-MESH
implementation (Espressif, 2024b), which supports
various configurations, including ”Internal Commu-
nication”, ”IP Internal Network”, and ”Manual Net-
working” (Espressif, 2024a). However, its functional-
ity is restricted to internal network communications,
as external devices (other Wi-Fi clients) cannot con-
nect to or interact with the mesh network.
Table 4 provides a comparison of the key fea-
IoTBDS 2025 - 10th International Conference on Internet of Things, Big Data and Security
380
Table 3: Comparison of native communication technology support in IoT devices.
Features /
Devices
Wi-Fi 6 ESP-NOW Bluetooth Thread ZigBee Avg. Price
Arduino
Nano ESP32
- - - 20$
Arduino
UNO Wi-Fi
REV2
- - - 25$
Espressif
ESP32-C6
8$
Raspberry
Pico W
- - - - 5$
Raspberry
Pi Zero W
-
Adapted
(Flayols, 2024)
- - 16$
Raspberry
Pi 5
Adapted
(Flayols, 2024)
- - 70$
tures from the mentioned articles and the pro-
posed architecture, including: MQTT over ESP-NOW
(MoE), Data-Plane Technology (DPT), Control-
Plane Technology (CPT), Self-Organisation/Healing
(SOH), SDN Capable (SDNC), Propagates Network
(PN), Internet Connection, (IC), Data and Control
Planes Separation (DCPS), Easy One-click Config-
uration (EOC), Monitoring (M), NAT Service (NS),
ESP-WIFI-MESH (EWM), Allow External Device
Connections (AEDC).
4 PROPOSED ARCHITECTURE
The work proposes a new architecture that integrates
IoT devices with Wi-Fi mesh network, to ensure net-
work access to nearby end devices. The selection of
Wi-Fi and ESP-NOW is critical for the architecture’s
scalability and efficiency. Wi-Fi ensures high data
transmission capacity and broad compatibility for the
data plane, while ESP-NOW enables low-latency and
energy-efficient operations for the control plane. This
combination leverages the strengths of both proto-
cols to enable concurrent operations across multiple
planes. This concurrent operation reduces interfer-
ence from each other and is crucial for the concurrent
use of both Wi-Fi and ESP-NOW.
Figure 1 illustrates the proposed architecture,
where connections between existing IoT devices cre-
ate a self-expanding mesh network. Wi-Fi and ESP-
NOW will work concurrently in different roles, acting
as the dual data plane and control plane, respectively,
to establish distinct production and management net-
works at separate layers. These run in the same inter-
face as shown in the figure 2.
The network includes a common router serving as
the internet gateway (where is possible to have multi-
Figure 1: Proposed mesh architecture with devices as
network propagators for both data and control planes.
Virtual
Interface 1
Virtual
Interface 2
Virtual
Interface
Device Interface
Data Plane (IoT) Control Plane
Wi-Fi
Thread
ZigBee
BLE
Wi-Fi
EspNow
HaLow
Data Plane (Wi-Fi ext)
Figure 2: Device with a single interface for both dual data
and control planes.
ple gateways) and a simple Wi-Fi Access Point (AP)
that connects directly to the router. Both allow wire-
less access for other devices, namely IoT devices with
sensors and/or actuators (e.g., smart light bulbs, smart
doors, or a smart appliance). The IoT devices use
the ESP-NOW protocol to communicate, selecting the
best route based on peer signal strength, reachable
APs/routers or other metric. They monitor changes
in their surroundings and adjust their connections,
which are visible and configurable through an SDN
Controller accessible to any device. After achieving
convergence, IoT devices configure the Wi-Fi mesh
Enhancing Scalability in Wi-Fi IoT Networks with Logical Data Plane Segregation Using SDN Principles
381
Table 4: Comparison between related work and proposed architecture features.
Features (Espressif,
2024b)
(Muhendra
et al., 2017)
(Gergeleit,
2019)
(Manvi and
Maakar,
2020)
(Khanchuea
and
Siripokarpirom,
2019)
Proposed
DPT Wi-Fi MoE Wi-Fi ad-hoc Wi-Fi Zig-Bee Wi-Fi
CPT Wi-Fi MoE NAT TCP ESP-NOW &
ModBus
ESP-NOW
SOH
SDNC - - - - -
PN - - -
IC - - -
DCPS - - - -
EOC - - - - -
M - - - -
NS - - -
AEDC - - - -
network by connecting to various APs/routers, ex-
tending the network using the same SSID. The Wi-
Fi mesh network remains active among IoT devices,
but broadcasting to end-user devices requires explicit
controller configuration. The IoT devices can per-
form their primary functions, including acquiring sen-
sor data, executing actuator tasks, and communicating
with the IoT data collector. End-user devices (laptops,
smartphones, etc.) can connect to the Wi-Fi network
via any AP/router or any IoT device broadcasting that
network.
Figure 3 illustrates the implementation process of
the architecture: starting with raw operation, con-
figuring interfaces and services, separating control
and data planes, initialising mesh networks for device
communication, and loading specialised software for
sensors or actuators.
Raw Operation
Initialization
Data Plane
Network
Configuration
Control Plane
Network
Configuration
Control Plane
Mesh
Initialization
Data Plane
Mesh
Initialization
Extra Software
Interfaces and
Services
Configuration
Figure 3: Proposal of the Software Flow the IoT devices.
5 IMPLEMENTED PROTOTYPE
Wi-Fi 6 is a relatively new technology in IoT terms
(Mozaffariahrar et al., 2022a), and manufacturers are
still in the process of adopting and releasing com-
patible devices. One such device is the Espressif
ESP32-C6 DevKitC-1 v0.0, which has been selected
for use in this project. This development board sup-
ports Wi-Fi 6, Bluetooth 5, Thread, and ZigBee com-
munications, according to the official documentation
(Espressif, 2023e), making it the first low-cost IoT de-
vice capable of implementing Wi-Fi 6 for mesh net-
work development. A necessary note, is that the de-
vice used in the present work is a sample version
(v0.0), it has power stability issues as noted in the
sample paper accompanying the device, ”The ADC
in the current samples is not calibrated”, and also
doesn’t support external antennas (The ESP32-C6-
WROOM-1U version, which came out later (Espres-
sif, 2024c) supports and has this problems addressed).
The implemented prototype was developed us-
ing the Espressif ESP32-C6, as it is currently the
only low-cost IoT device meeting the necessary re-
quirements for the intended functionality (Espressif,
2023g). This device can communicate using both
protocol stacks concurrently via a single antenna, en-
abling the separation of the planes, with Wi-Fi serv-
ing the data plane (wireless clients) and ESP-NOW
for the control plane (IoT devices).
The dual data plane is constructed atop a mesh
network, where each device forwards data to the next
one until it reaches a gateway (an access point or
router). This implementation was necessary because
native routing cannot be set up directly on the de-
vice (Espressif, 2023a) (Espressif, 2020a) (Espressif,
2015). By this, it is meant that the devices select
the next hop by signal strength. The routing is han-
dled simply by the inherent features of a NAT device.
As such, it uses a NAT mechanism to forward traffic
(Gergeleit, 2019). Implementing NAT in this specific
context has performance costs, especially for devices
closest to the gateways due to high traffic volumes and
the number of dependent devices. Consequently, a re-
striction imposed by the manufacturer only allows up
to 17 connections (Espressif, 2024d) to be connected
to each network node. This value is further reduced to
8 devices per interface due to the requirement of two
virtual interfaces per node (6 devices and 2 nodes per
interface), and this can be rearranged according to the
necessities up to 8 slots per interface.
IoTBDS 2025 - 10th International Conference on Internet of Things, Big Data and Security
382
For the control plane, several technologies and
protocols are suitable for IoT communications, in-
cluding ZigBee, Thread, BLE, HaLow, and ESP-
NOW. Although all these protocols could theoreti-
cally implement a wireless communication architec-
ture, only ESP-NOW fully meets the requirements for
this specific use case. See section 2 for further details.
The device broadcasts a packet every 10 seconds
to announce its presence to other nearby devices.
There are two packet types: a search packet and a
keep-alive packet, and both currently transmit iden-
tical information, differ only in retransmission inter-
vals. The keep-alive packet having the longest inter-
val. When a neighbouring device receives a packet,
it checks whether the sender is already in the cached
neighbours list, if it exists, its dead timer is set to 0,
or else it increments.
In addition to the aforementioned, the device also
scans periodically for Wi-Fi access points in the vicin-
ity and then selects the nearest gateway/mesh. Before
connecting to any node (device or gateway), a false
positive check is performed three times, and if vali-
dated, the device attempts the connection, otherwise,
it attempts on another node. The process repeats ev-
ery 10 seconds for unconnected nodes and 30 seconds
for connected ones. These values were chosen as de-
fault settings to balance responsiveness and resource
usage. While they have not been experimentally vali-
dated, they can be adjusted based on specific applica-
tion needs in future work.
6 RESULTS
The prototype testing aimed to record the overall net-
work uptime, from boot to full operational mode,
and assess stability and performance using tools like
iperf3, hping3, nuttcp, and ping. The tests were con-
ducted using four devices spaced between 1 and 15
metres apart (1, 5, 10, and 15 metres), covering up
to 50 metres in a linear hop-by-hop mesh configu-
ration. While this approach allowed for straightfor-
ward evaluation of individual hops, it does not fully
exploit the resilience and redundancy typically asso-
ciated with mesh networks. In this setup, failure of
an intermediary node disrupts service for subsequent
nodes. Although the development of the project used
a full mesh topology, the testing phase employed a
hop-by-hop NAT configuration for practical evalua-
tion of individual node performance. The same mesh
code was utilised in the test environment, ensuring
consistency between the mesh architecture and the
test configuration. Future testing should investigate
the use of a mesh topology with more devices.
To streamline test execution, a Python script was
developed, incorporating both client and server re-
quirements in separate threads. The script’s server
mode provides an HTTP server to monitor device
readiness in the network, a Mosquitto server for re-
sult sharing, a nuttcp server to test throughput, and
an iperf3 server for bandwidth and data loss analysis.
Figure 4 illustrates the setup and the communication
between them, forwarded by the Espressif devices.
All devices have a default route to ensure connectivity
to the server and the Internet.
Figure 4: Arrangement of test equipment.
Table 5 summarises the results of the network
setup readiness and convergence tests, measuring up-
time from a cold boot at various distances. Each net-
work configuration was tested 10 times with different
device quantities, totalling 40 tests (4 devices × 10
tests each). The overall average uptime across all dis-
tances was 28.75 seconds.
Table 5: Average uptime submitted by the devices.
Devices \Distance 1m 5m 10m 15m
Device 1 30s 30s 30s 30s
Device 2 26s 26s 26s 28s
Device 3 29s 30s 51s 26s
Device 4 50s 50s 148s 28s
Table 6 displays the response times and packet
loss rates measured by the ping tool, which gradually
increase with the distance between devices. Nuttcp
tools in 7, shows that results degrade as the dis-
tance increases, leading to higher response times.
This results in longer Round-Trip Times (RTT), re-
duced throughput, and increased packet loss. Re-
transmissions were not observed. All the results are
a compilation of 10 tests. The iperf3 results in table
8 also highlight the trend of significant performance
degradation with increasing distance. However, when
using UDP, the connection maintains a stable rate of
1.05 Mbits/sec.
Table 6: Ping tool results.
Ping \Distance 1m 5m 10m 15m
Minimum 6.982ms 10.859ms 8.834ms 6264.071ms
Average 17.482ms 33.028ms 18.113ms 7078.394ms
Maximum 51.641ms 130.871ms 42.200ms 8609.763ms
Packet Loss 0% 0% 0% 50%
Enhancing Scalability in Wi-Fi IoT Networks with Logical Data Plane Segregation Using SDN Principles
383
Table 7: Nuttcp results.
Nuttcp \Distance 1m 5m 10m 15m
TCP Throughput 6.7604 Mbps 2.1619 Mbps 0.0524 Mbps -
TCP RTT 7.98ms 10.59ms 154.43ms -
TCP Retrans 0 0 0 -
UDP Throughput 1.0002 Mbps 1.0012 Mbps 0.2756 Mbps 0.0164 Mbps
UDP Packet Loss 0% 0% 66.18% 98.69%
Table 8: Iperf3 TCP, UDP, retries and jitter results.
iperf3
\Distance
1m 5m 10m 15m
TCP 7.15 Mbits/sec 2.25 Mbits/sec 78.6 Kbits/sec -
UDP 1.05 Mbits/sec 1.05 Mbits/sec 1.05 Mbits/sec -
Retry 17 9 2 -
Jitter 1.096 ms 3.996 ms - -
7 DISCUSSION
The prototype demonstrates the use of a single an-
tenna to accommodate the two data planes and a con-
trol plane. The antenna is used for three roles: IoT
client, access point for IoT end devices, and manage-
ment network. While the client and access point rely
on Wi-Fi 6, the management network uses ESP-NOW.
The use of a single-antenna design aims to deliver
functionality for existing devices at a low cost. Multi-
ple antennas could improve system performance, but
may shift the focus from simple, low-cost solutions to
complex implementations.
A concern on the prototype is the use of NAT in
the Lightweight TCP/IP (LwIP) stack that does not
support creating a network bridge, and as a solution
NAT was used instead, resulting in an inherent ”de-
lay” when many client devices are present in the net-
work, as it works like a funnel. While there is an
Ethernet Network Interface Card (NIC) based solu-
tion (Espressif, 2023b), the LwIP stack currently only
supports Ethernet interfaces for bridging. Each node
is limited to 8 connected devices (Espressif, 2024e)
an can be configured up to 17 different devices.
The use of NAT was necessitated by the lack of
support for direct interface bridging in the current de-
velopment framework. While NAT offers advantages
such as simplified route creation and privacy protec-
tion, its inherent limitations, including increased la-
tency and reduced number of connected neighbors,
highlight the need for future code framework im-
provements to support direct bridging for enhanced
performance. However these inherent limitations do
not affect the scalability of the mesh network.
The testing revealed coverage limitations possi-
ble due to a single antenna, IoT nature, and experi-
mental software/hardware. The best stable outcome
was achieved with devices with 10 metres, and reach-
ing up to 50 metres for a usable network. The data
shows that device uptime is relatively stable around
30 seconds, with constraints based on the connection
time from lower layers. If layer 3 devices cannot boot
due to layer 2 devices being inactive, subsequent lay-
ers wait for predefined time intervals to recheck and
establish connections. Performance degradation be-
yond 10 metres is likely attributed to a combination of
factors, including the prototype’s development stage,
lack of external antennas, unoptimised code, and the
simultaneous use of multiple planes with a single an-
tenna attempting concurrent operations. Addressing
these hardware and software limitations could signif-
icantly enhance range and stability.
8 CONCLUSION
The paper presents a dual data plane architecture and
functional prototype enabling new and existing IoT
devices to establish their own mesh network while
separating data streams. It achieves this by allowing
devices to communicate via ESP-NOW for settings
adjustments and decision-making, thereby fostering
autonomous operation within the network, while the
Wi-Fi planes handle IoT functionality and Wi-Fi ac-
cess to end devices. The architecture supports concur-
rent operation of Wi-Fi 6 and ESP-NOW on ESP32-
C6 (v0.0) devices, utilising a single 2.4 GHz inter-
face. This setup enables devices to manage control
independently without requiring an SDN Controller
or central device, though it remains compatible with
such configurations if needed.
Future work should focus on seamless integra-
tion across multiple vendors and broader testing un-
der varied conditions. While this work does not en-
compass a detailed security analysis, future iterations
could include exploring security challenges specific
to ESP-NOW and mesh architectures. The integra-
tion of artificial intelligence techniques and a SDN
controller can improve network performance through
data-driven optimisation, failure prediction, and real-
time parameter adjustments. Code revisions can im-
prove environment scanning, routing, and updating
neighbour statuses. A study should investigate effi-
ciency challenges and security aspects in communi-
cations, particularly in the ESP-NOW protocol.
ACKNOWLEDGEMENTS
This work was funded by FCT Fundac¸
˜
ao para
a Ci
ˆ
encia e Tecnologia, I.P. under the project
UIDB/04524/2020.
IoTBDS 2025 - 10th International Conference on Internet of Things, Big Data and Security
384
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