Xelivor
Xelivor
In modern telecom systems and high-density computing infrastructure, link verification is paramount. Xelivor Optoelectronics Co., Ltd. stands as a premier manufacturer of high-precision optical transceivers, network interfaces, and Ethernet loopback connectors. Established in 2016, we have dedicated over 8 years of manufacturing excellence to addressing complex link validation challenges for hyperscale data centers, cloud infrastructure, and telecom systems worldwide.
Equipped with a state-of-the-art facility, our engineering teams build testing and diagnostic modules designed to withstand rigorous deployment cycles. We specialize in providing the critical hardware that network administrators, QA laboratories, and telecom field crews rely on to debug physical layer connectivity issues, map performance limits, and verify loopback signal paths.
Explore our curated selection of high-frequency optical transceivers, RJ45 ports, and interface components designed to facilitate precise signal routing and diagnostic capabilities in next-generation networks.
In high-density networking, isolating localized port faults from transmission cable failures represents a major operational challenge. An Ethernet loopback connector (commonly known as a loopback plug or adapter) serves as an essential tool. By redirecting the transmitter output (Tx) directly back into the receiver input (Rx) on the same port, the loopback adapter simulates an active network connection. This configuration allows technicians and diagnostic hardware to run loopback tests, validating host hardware controllers, operating system drivers, and local physical ports without introducing external network variables.
While software-defined routing can simulate loopback states at the virtual layers, physical loopback plugs remain the gold standard for testing raw copper connectors and optical channels. For instance, in standard 10/100Base-T Ethernet, a loopback plug cross-connects the transmit pairs to the receive pairs (Pins 1 & 2 linked to Pins 3 & 6). In Gigabit (1000Base-T) copper networks, where all four pairs transmit simultaneously, the loopback plug utilizes specialized internal crossover wiring arrays (Pin 1 to 4, Pin 2 to 5, and Pin 7 to 8) to route the high-frequency differential signals, ensuring the PHY chip can complete auto-negotiation and link-up parameters.
The design architecture of loopback systems changes significantly based on the medium. A standard RJ45 loopback uses hardwired pathways within a molded connector shell to guide electrical pulses. In contrast, optical loopback connectors (such as LC, SC, MPO, or SFP/SFP+ optical loopbacks) loop the optical fiber signal back into the receiver. Because laser transmitters emit specific light intensities, optical loopbacks often incorporate attenuators (ranging from 1dB to 10dB) to prevent optical receiver saturation and damage, mimicking the loss values typically found across a standard fiber-optic link.
Designed for RJ45 ports. Typically features compact, molded configurations with precise internal wire bridging. Ideal for testing network interface cards (NICs), patch panels, and switchboards.
Designed for SFP, SFP+, QSFP28, and newer transceiver modules. Configured with single-mode or multi-mode fiber loops. Attenuation modules are integrated to safeguard optical receiver circuits.
Advanced hardware solutions containing transceivers and loopback circuitry in a single assembly, enabling fast QA sweeps across ports without requiring standalone cabling.
From regional optical fiber deployments in Europe to hyperscale data center nodes in North America, loopbacks provide critical support for field testing and infrastructure validation.
Before launching a rack or row, network engineers deploy loopback connectors to simulate active links across hundreds of optical paths. This process allows them to confirm line integrity, verify patch panels, and identify connection faults before installing active servers.
Telecom carriers utilize loopback tests to troubleshoot fiber runs reaching up to 80km. By installing an optical loopback at the remote terminal, local operators can perform Bit Error Rate (BER) tests and measure optical insertion losses directly from the central office.
In environments prone to electrical noise, engineers deploy loopbacks to evaluate the shielding integrity of RJ45 connections and EMI cages. This ensures industrial PLC and robotic controls maintain reliable communications under heavy operational loads.
As global networks transition from 10G/40G toward 100G, 400G, and 800G, loopback diagnostic requirements are shifting toward high-frequency, multi-lane transceivers (QSFP-DD and OSFP). At these high transmission speeds, passive copper loopbacks are increasingly limited by insertion losses, driving the adoption of high-performance optical loopbacks. Additionally, the rise of Edge Computing facilities requires ruggedized, temperature-resistant loopback modules capable of reliable operation in uncooled outdoor enclosures.
The continuous growth of AI-driven computing and machine learning clusters requires highly optimized, low-latency interconnects. As speeds push beyond 800G toward 1.6T, physical interface tolerances are shrinking. Xelivor's engineering roadmap focuses on addressing these demands through innovative hardware and component development:
Developing high-density optical loopbacks for 12-fiber and 24-fiber arrays to support multi-lane configurations (QSFP28/QSFP-DD) with low-profile housings.
Integrating DDM circuits directly into diagnostic loopback packages, enabling real-time voltage, temperature, and optical power feedback during testing.
Designing ultra-low insertion loss loopbacks for silicon photonics and co-packaged optical systems, helping scale future AI switch clusters.
Our manufacturing operations leverage China's deep electronics supply chain to offer competitive, high-quality interconnect solutions. Xelivor's specialized optical transceiver facility integrates design, engineering, and quality assurance into a unified workflow:
Our quality control program spans incoming raw material inspections, in-process assembly checks, compatibility verification across major host platforms, and final optical parameter testing. Led by 32 professional QA inspectors, this comprehensive process ensures every component meets international standards before delivery.
Xelivor maintains active partnerships with over 850 component suppliers. This extensive network ensures access to high-grade PCBs, plastic shells, optical sub-assemblies (TOSA/ROSA), and semiconductor chips, mitigating production disruptions and stabilizing lead times.
Backed by 68 R&D engineers, we offer flexible OEM and ODM services. From customized firmware compatibility configurations to custom labeling and packaging, we design systems tailored to local regulatory requirements across North America, Europe, and Asia.
Our second collection features high-speed SFP+ modules, shielded cages, stacked RJ45 connectors, and high-performance network interface adapters.
Find answers to frequently asked technical questions regarding loopback test setups, attenuation requirements, and transceiver integration.
In standard 10/100Base-T network interfaces, only two pairs are active, meaning pin 1 maps to pin 3 and pin 2 maps to pin 6. In contrast, 1000Base-T (Gigabit Ethernet) utilizes all four wire pairs. To construct a working Gigabit copper loopback plug, you must cross-connect all four pairs: Pin 1 (BI_DA+) to Pin 4 (BI_DD+), Pin 2 (BI_DA-) to Pin 5 (BI_DD-), Pin 3 (BI_DB+) to Pin 7 (BI_DC+), and Pin 6 (BI_DB-) to Pin 8 (BI_DC-).
Standard optical transceivers are configured to transmit light over significant distances. When directly connecting the transmitter (Tx) to the receiver (Rx) with a short loopback cable, the raw optical energy can easily exceed the receiver's threshold, causing saturation or hardware damage. Integrating a 5dB or 10dB attenuator simulates the signal loss of a standard fiber run, ensuring safe optical power levels during testing.
Yes. Modern switches and routers run proprietary hardware validation protocols. Standard optical loopback hardware might not negotiate properly if the device does not recognize the module. Xelivor's engineering team provides customized EEPROM and MCU firmware options to ensure compatibility with major platforms, including HPE, Aruba, Cisco, H3C, and others.
Every product undergoes a comprehensive quality check before shipment. For optical transceivers, this includes eye-pattern analysis, optical power output measurements, spectral wavelength testing, and host compatibility verification. For copper connections, we verify pin configuration mapping, signal continuity, and EMI shielding effectiveness.
Step inside Xelivor's modern production cleanrooms, advanced optoelectronics testing laboratories, and automated manufacturing lines.
