I. Technical Background: Industrial IoT Demands More From Wireless Networks
As Industry 4.0 continues to advance, industrial IoT has become a core driver of digital transformation in manufacturing. However, the unique nature of industrial environments means their requirements for wireless networks are far more demanding than home or office scenarios — devices must maintain stable connections under high temperatures, low temperatures, vibration, and electromagnetic interference, with data transmission that cannot tolerate packet loss, disconnection, or latency.
At the same time, many factories and hospitals that have relied on wired equipment for years face a dilemma: replacing equipment with new models is prohibitively expensive, but keeping the old equipment means it cannot meet new demands for flexible mobility and remote management.
How can these "wired devices" gain wireless capability without replacing the original equipment? This is the central challenge in wireless transformation for industrial and medical settings.
Ethernet-to-Wi-Fi Layer 2 bridging technology is precisely the key to solving this challenge.
II. Core Technical Principles: Ethernet-to-Wi-Fi Layer 2 Bridging Technology and Its Mechanism
Technical Definition
The core of Ethernet-to-Wi-Fi bridging technology can be precisely defined as "Translational Bridging." It differs fundamentally from "transparent bridging" between devices of the same medium (such as switches), because it must perform bidirectional "translation" and conversion between two completely different frame formats — IEEE 802.3 (Ethernet) and IEEE 802.11 (Wi-Fi) — at the data link layer (Layer 2).
This process is far more complex than a simple "connection" — it is a precise and intelligent protocol conversion process.
Core Differences Between Ethernet and Wi-Fi Frames: Two Different "Languages"
Ethernet and Wi-Fi frame formats differ significantly. A standard 802.11 frame header is considerably more complex than an 802.3 frame header, containing additional control fields for managing wireless transmission.
Layer 2 Bridging Principles
The Translation Process: How the "Language" Is Converted
The job of a translational bridging device (such as a Wi-Fi access point) is to perform precise conversion between these two "languages."
Direction 1: Wi-Fi → Ethernet (Wireless to Wired)
When data is sent from a Wi-Fi client to the wired network, the device performs the following reverse conversion:
Receive and Verify: Receive the 802.11 frame, check its integrity, and verify the Frame Check Sequence (FCS).
Filter and Deduplicate: Check whether the frame's BSSID matches, and remove duplicate frames caused by wireless transmission.
Decrypt and Reassemble: Decrypt the frame if it is encrypted; reassemble it into a complete frame if it has been fragmented.
Frame Header Conversion (Key Step): This is the core translation work.
Destination MAC: Copied from the Address 3 field of the 802.11 frame header to the Ethernet frame header.
Source MAC: Copied from the Address 2 field of the 802.11 frame header to the Ethernet frame header.
Type: The upper-layer protocol type (such as IP) is extracted from the SNAP (Subnetwork Access Protocol) header within the 802.11 frame's data portion and inserted into the Ethernet frame's Type field.
QoS Mapping (Optional): If needed, map 802.11 QoS information to Ethernet's 802.1p priority.
Forward: Send the newly generated 802.3 Ethernet frame out through the wired interface.
Direction 2: Ethernet → Wi-Fi (Wired to Wireless)
This is the reverse of the above process, sending data from the wired network to the Wi-Fi client:
Receive and Verify: Receive the 802.3 Ethernet frame and verify its FCS.
Filter: Check whether the frame's destination MAC address belongs to a currently associated wireless client.
SNAP Encapsulation: Insert the Ethernet frame's Type field information into a SNAP header and attach it in front of the data payload.
Frame Header Conversion: Insert the destination and source MAC addresses from the Ethernet frame header into the corresponding Address fields of the 802.11 frame header.
Queue and Schedule: Place the frame into the send queue for scheduling according to QoS policy.
Encrypt and Fragment (Optional): Encrypt the frame according to security policy and fragment it if necessary.
Forward: Send the newly generated 802.11 frame out through the wireless interface.
Intelligent Forwarding: MAC Address Learning
While "translating" frames, the device also performs intelligent forwarding, the core of which is maintaining a MAC address table.
Learning Process: When a data frame enters through a given interface (such as Wi-Fi), the device records the source MAC address and its corresponding interface, storing this in the MAC address table.
Forwarding Decision: When a frame with destination MAC address X is received from another interface (such as Ethernet):
Precise Forwarding: The MAC address table is queried; if X is found, the converted frame is sent out only through the corresponding interface (Wi-Fi).
Flooding: If X is not found, the frame is forwarded to all other interfaces (except the receiving port).
Advanced Features
A mature translational bridging device also involves the following capabilities:
Spanning Tree Protocol (STP): To prevent network loops, the device runs the STP protocol, building a loop-free network topology by logically blocking redundant paths.
VLAN Support: Advanced devices can handle VLAN-tagged (802.1Q) frames, preserving or converting VLAN information during the conversion process.
Performance Optimization: Many devices use fast Layer 2 forwarding technology, using hardware caching to record data flow information and accelerate the forwarding of subsequent frames from the same flow.
III. Bridge Product Line: Full Coverage From Medical to Heavy Industry
Building on this core technology, Alinket has launched three Ethernet-to-Wi-Fi bridge products, each targeting a different application scenario.
ALXB10: Medical-Grade Lightweight Bridge, Plug-and-Play
The ALXB10 is Alinket's lightweight bridge designed for medical and healthcare scenarios. With a built-in antenna and an extremely compact size (64×49×21mm, just 40g), it connects to wired medical equipment through a single RJ45 port. Configuration can be completed quickly using a dedicated PC configuration tool, with no professional network engineer required.
Its ultra-low power consumption (1.2W standby) and wide operating temperature range (-40°C to 85°C) ensure long-term stable operation in all types of hospital environments, making it the preferred choice for wireless transformation of wired medical devices such as patient monitors, ECG machines, and ventilators.
Core Specifications:
ALXB15i: Industrial-Grade Flagship Bridge, Stable and Reliable
The ALXB15i is Alinket's flagship product for industrial scenarios. Building on the lightweight model, it introduces external dual antennas (MU-MIMO) and Wi-Fi 5 (802.11ac) protocol support, delivering faster transmission and stronger interference resistance to handle the complex electromagnetic environments of factory workshops. The aluminum alloy housing offers excellent heat dissipation and effectively resists corrosion, meeting industrial-grade usage requirements.
Since its launch, the ALXB15i has been deployed in real-world applications across multiple industrial sectors including automotive manufacturing, smart logistics, and energy and mining, making it the core solution for AGV roaming connectivity and wireless transformation of workshop equipment.
Core Specifications:
ALX-MWB524F: Heavy-Industry Flagship, Multi-Port Seamless Roaming
The MWB524F is Alinket's flagship product built specifically for ultra-high-reliability industrial Wi-Fi applications. Using a proprietary architecture and algorithm design, it features enterprise-grade capabilities including dual Wi-Fi hot standby, wireless link protection, and link aggregation. Its 4 RJ45 ports can simultaneously connect up to four wired devices, and its wide voltage input (DC 9V–36V) adapts to various industrial power supply environments, while its metal housing withstands extreme operating conditions.
Core Specifications:
Core Advantages: Dual Wi-Fi hot standby + wireless link protection ensures switchover without disconnection or packet loss; wireless link aggregation effectively expands bandwidth; full Layer 2 switching with complete protocol transparency, compatible with all Ethernet frame types.
IV. Application Scenarios and Success Cases
Scenario 1: Wireless Transformation of Medical Equipment (ALXB10)
Pain Point: Legacy wired medical equipment in hospitals — patient monitors, ECG machines, ventilators, mobile X-ray machines — can only connect to the network via Ethernet ports, preventing flexible movement and integration into smart hospital wireless management systems. Replacing all equipment with new models is extremely costly and the transformation cycle is long.
Solution: Connecting the ALXB10 to the medical device via its RJ45 port is plug-and-play — the device gains Wi-Fi connectivity immediately without any changes to its internal structure. Bedside monitors can connect to the central nursing station system, and mobile equipment can move freely within the hospital's Wi-Fi coverage area.
Success Case — Wireless Mobile X-Ray Machine: A hospital's legacy mobile X-ray machine only supported wired connections, limiting its operational scenarios. After adding an external ALXB10 bridge, the X-ray machine could move freely within the hospital's Wi-Fi range without any modification to the machine's internal structure. The equipment's usable lifespan was significantly extended, and the transformation cost was far lower than purchasing a new machine.
Success Case — Wireless Bedside Monitors and ECG Machines: A hospital's legacy bedside monitors, ECG machines, and similar equipment only supported wired connections, restricting their use to fixed bedside locations and preventing them from meeting the mobile management needs of smart hospitals. After adding external ALXB10 bridges, the devices connected to the central nursing station system via the hospital's Wi-Fi network, allowing flexible movement within the ward without any modification to the equipment's internal structure. The equipment's usable lifespan was significantly extended, and the transformation cost was far lower than purchasing new machines.
Scenario 2: AGV/AMR Seamless Roaming Connectivity (ALXB15i)
Pain Point: AGVs and smart forklifts move continuously throughout the factory, needing to cross multiple AP coverage zones. Traditional Wi-Fi solutions often experience disconnections during AP handoffs, causing AGVs to stall, take wrong routes, or stop entirely — directly impacting production efficiency and safety.
Solution: The ALXB15i supports fast roaming, with AP-to-AP handoff time controlled at the millisecond level, fundamentally eliminating packet loss during handoffs. It connects directly to the AGV controller via its RJ45 port, is powered via Micro USB, and its compact size makes integration easy.
Success Case — AGV Roaming Solution: A smart logistics client deployed an AGV roaming solution using the ALXB15i, resolving a long-standing critical wireless handoff issue in their project. The system achieved essentially zero disconnections under full operational load. The partner was highly satisfied with the results and sent a formal letter of appreciation.
Scenario 3: Wireless Transformation of Automotive Workshop Equipment (ALXB15i)
Pain Point: In automotive final assembly workshops and engine component production workshops, large amounts of industrial CNC equipment and robotic arms rely on wired connections, resulting in complex cabling, difficulty relocating equipment, and challenges achieving unified remote control and management.
Solution: The ALXB15i uses its underlying technology to achieve conversion and integration between industrial Ethernet and industrial wireless networks, quickly and stably completing the encoding/decoding conversion of data between wired and wireless industrial equipment — well-suited for industrial wireless transformation scenarios.
Success Case — Deployment Across Multiple Major Automotive Brands: The ALXB15i has been successfully tested and commercially deployed in workshops across multiple well-known automotive brands, covering both final assembly workshops and engine component production workshops. After multiple rounds of stress testing, it maintained stable performance under near-full operational load, with performance exceeding comparable client products currently on the market.
Scenario 4: Industrial Automation and Mobile Control Management (MWB524F)
Pain Point: Large mobile industrial equipment such as rail-guided vehicles, gantry cranes, and workshop sliding rails need to maintain real-time data exchange with the networked control center during operation, while potentially needing to connect to multiple control devices simultaneously — a requirement that single-port solutions cannot meet.
Solution: The MWB524F is equipped with 4 RJ45 ports that can connect up to four devices simultaneously. Combined with MU-MIMO low-latency, interference-resistant capability and a dual Wi-Fi hot-standby architecture, it provides continuous and stable multi-path wireless connectivity for large mobile industrial equipment, enabling unified wireless mobile control and management.
Scenario 5: Factory-Wide Network Interconnection (MWB524F)
Pain Point: Physical separations between workshops and buildings within a factory often make cabling costly or construction difficult, leaving network segments in different areas isolated from one another. Traditional WDS interconnection solutions also frequently face compatibility issues between devices from different manufacturers due to a lack of unified standards.
Solution: The MWB524F supports standard Layer 2 bridging interconnection, enabling network connectivity within workshops, across storage areas, and between buildings. It is broadly compatible with mainstream AP equipment, offering flexible deployment that is not restricted to a single brand.
Scenario 6: Energy and Special Operating Conditions (ALXB15i)
Pain Point: Environments such as coal mines and petrochemical facilities are extremely harsh, combining high dust, high humidity, and complex electromagnetic interference, placing extreme demands on a device's corrosion resistance, heat dissipation, and shock resistance — requirements that standard consumer-grade wireless equipment cannot meet.
Solution: The ALXB15i's aluminum housing provides excellent heat dissipation and effective corrosion resistance, operating stably across a wide temperature range of -30°C to 85°C, meeting the demanding requirements of special operating conditions in the energy sector.
Success Case — Smart Coal Mine: A smart coal mine project deployed the ALXB15i within the transportation and monitoring wireless communication network in the mine shaft environment. It operated stably under conditions of high dust, high humidity, and complex electromagnetic interference, meeting the stringent requirements for wireless communication in mining scenarios.
V. Product Comparison: Selecting the Right Model
VI. Conclusion
Ethernet-to-Wi-Fi Layer 2 bridging is a "translation" process performed at the data link layer — one involving loss and selective decision-making. It is not simply a "connection," but the precise translation of one "language" (802.3 frames) into another (802.11 frames), with intelligent forwarding decisions made throughout the process. This process is far more complex than transparent bridging between devices of the same medium, and it is the key technology that enables devices such as Wi-Fi access points (APs) to bridge the wired and wireless worlds.
Building on this core technology, Alinket has constructed a complete bridge product line spanning from lightweight medical applications to heavy-industry flagship solutions. Whether it's wireless transformation for a single piece of hospital monitoring equipment, seamless roaming for factory AGVs, or network interconnection across separated workshop buildings, Alinket's bridge products deliver plug-and-play solutions on the ground — no equipment replacement, no new protocols, no rewiring — completing IoT upgrades at minimal transformation cost.
