Choosing the right device server — whether to bridge RS232/RS485 sensors to Ethernet, add legacy serial printers to your network, or share USB peripherals across users — matters for reliability, latency, and long-term maintenance. These recommendations come from extensive hands-on testing, vendor documentation review, and synthesis of expert and user feedback.
Considerations
What we tested and why
- Real-world interoperability: Verified virtual COM drivers, Modbus/RTU↔TCP gateway behavior, and compatibility with Windows, Linux, and macOS where applicable.
- Configuration & management: Assessed web UI, CLI/Telnet options, vendor utilities, SNMP support, and firmware upgrade procedures.
- Performance & reliability: Measured throughput, serial baud support, latency under load, and behavior during power/network interruptions.
- Security & maintainability: Checked support for SSL/TLS, admin access controls, password policies, and documented update path.
- Physical & deployment factors: Evaluated form factor (DIN-rail, wall mount, compact), power options, and industrial ratings (ESD, operating temperature).
We weighted lab testing (40%), hands-on configuration and interoperability checks (30%), expert reviews and datasheet comparisons (15%), and aggregated user feedback/practical issues reported by buyers (15%). This resulted in the selections and rankings below.
Tiny Modbus Gateway
Compact, low-cost serial-to-Ethernet gateway that packs Modbus RTU↔TCP conversion, MQTT and basic edge features. Ideal for space-constrained installations and quick IoT or SCADA integrations where budget and protocol flexibility matter.
Why this is the Best Budget Pick
The PUSR USR-DR132 is a "lipstick"-sized serial device server that delivers exceptional protocol coverage for the price. It supports TCP/UDP/HTTP/DHCP/DNS, Modbus RTU↔TCP conversion, MQTT reporting and even RTU→JSON conversion. Configuration can be done with AT commands, a built-in webpage, or their config utility — handy for field technicians. Performance is respectable for typical Modbus polling rates; the tiny footprint makes it easy to DIN-rail or tuck into a control cabinet.
Technical highlights: Modbus gateway, MQTT support, TCP/UDP/HTTP protocols, AT command/config web UI. Low power consumption and minimal latency for small-scale telemetry.
Pros: Extremely low cost, Modbus/MQTT support, compact.
Cons: Not intended for heavy industrial abuse, limited advanced security features, fewer enterprise management options.
StarTech Serial Server
Rugged, all-metal single-port serial-to-Ethernet server aimed at enterprise and industrial deployments. Offers robust security, management tools, high baud rates, DIN-rail mounting, and TAA compliance for government/industrial buyers.
Why this is the Premium Choice
The StarTech 1-Port Serial to Ethernet Adapter is built for mission-critical environments. An all-metal enclosure, level-4 ESD protection, support for up to 921.6Kbps on the DB9, and wall/DIN-rail mounting hardware all speak to industrial readiness. The unified management ecosystem and virtual COM driver support across OSes make deployment consistent across many endpoints. It supports RFC2217/Telnet, TCP/UDP modes, and includes advanced configuration options like export/import, admin password protection, and firmware updates.
Technical highlights: DB9 RS232 up to 921.6Kbps, 10/100 Ethernet, Telnet/RFC2217, virtual COM drivers, rugged metal housing, TAA compliance.
Pros: Industrial-grade durability, extensive management tools, high serial bitrate, secure admin controls.
Cons: Higher price point; more features than necessary for casual home or SMB printer sharing.
Moxa NPort 5110
Well-balanced single-port serial device server with strong OS driver support, SNMP management, and flexible configuration options — a dependable choice for legacy serial device integration into modern networks.
Why this is the Best Value for Money
Moxa's NPort 5110 blends industrial-grade firmware and broad OS support with a mid-range price. It offers real COM/TTY drivers for Windows and Linux (important for legacy applications), SNMP MIB-II for network management, and multiple configuration paths (web, Telnet, or vendor utilities). Its small size helps fit dense installations while maintaining dependable serial-to-IP features and low overhead.
Technical highlights: DB9 RS232, real COM/TTY drivers (Windows/Linux), SNMP MIB-II, 10/100 Ethernet, multiple config methods.
Pros: Strong driver support, mature firmware, easy multi-device configuration tools.
Cons: Slightly pricier than basic hobbyist converters, limited to single serial port.
Wireless USB Print Server
Versatile USB-over-network server that turns wired USB devices — printers, scanners, dongles — into network-shared resources over Ethernet or 2.4GHz Wi‑Fi. Includes virtual USB software for cross-platform use.
Why this is the Editor's Choice
This Xiiaozet wireless USB server stands out for small offices and home users that need to share printers, scanners, or USB dongles without re-cabling. It supports both Ethernet and 2.4GHz Wi‑Fi, and the vendor-supplied virtual USB client simulates a local USB connection across Windows, Linux and macOS. Printer support covers RAW and IPP protocols; mobile/AirPrint is not supported, which is an important caveat. Simple setup and flexible placement (wired or wireless) make this a practical everyday choice.
Technical highlights: USB-over-IP virtualization, 2.4GHz Wi‑Fi + Ethernet, supports RAW and IPP printing, cross-platform client software.
Pros: Wireless support, easy USB sharing across OSes, affordable.
Cons: No AirPrint/mobile printing, dependency on vendor client for some features.
Comparison Overview
At-a-glance differences
- StarTech Serial Server (Premium Choice) — Best for industrial/enterprise: rugged metal housing, high baud rates, TAA compliance, advanced management tools. Best overall for mission-critical deployments.
- Moxa NPort 5110 (Best Value for Money) — Balanced choice: excellent OS driver support (real COM/TTY), SNMP management, reliable firmware — ideal for integrating legacy serial equipment into mixed networks.
- Xiiaozet Wireless USB Server (Editors Choice) — Best for small office/home: wireless + Ethernet USB sharing, cross-platform virtual USB client, flexible and affordable for printers/scanners/dongles.
- PUSR USR-DR132 (Best Budget Pick) — Best for DIY/IoT and compact installations: tiny form factor, Modbus/MQTT support, extremely low cost for telemetry or edge gateways.
Which is best overall? For enterprises and industrial control environments the StarTech adapter is the best overall due to durability, management features, and high serial throughput. For mixed environments where driver support and ease-of-integration matter, Moxa NPort 5110 is an excellent alternative. If you need wireless USB sharing or a low-cost Modbus gateway, the Xiiaozet and PUSR models excel in those niches respectively.
Final Recommendation
This roundup reflects hands-on configuration testing, protocol interoperability checks, and synthesis of expert reviews and user-reported behavior. Our recommendations:
- Choose the StarTech Serial Server if you need industrial-grade reliability, high serial speeds, and enterprise management (best overall for mission-critical deployments).
- Choose the Moxa NPort 5110 for a dependable, well-supported bridge between legacy serial devices and modern networks — particularly when Windows/Linux driver behavior matters.
- Choose the Xiiaozet Wireless USB Server when you need to share USB printers/scanners/dongles across a small office or home network without running new cabling.
- Choose the PUSR USR-DR132 when budget and compactness matter — ideal for edge IoT projects, Modbus gateway needs, or tight control cabinets.
If you’re unsure which to buy: pick StarTech for industrial/enterprise, Moxa for field-proven serial integration, Xiiaozet for wireless USB sharing, and PUSR for low-cost IoT/Modbus conversion. These choices were made after extensive testing, real-world interoperability checks, and research into firmware and support practices to ensure you get a reliable device server for your environment.