Cabling Chronicles
Fiber Polarity Basics for Duplex Applications
Fiber polarity is the direction that light signals travel from one end of a fiber optic cable (link) to the other. A link’s transmit signal (Tx) must match its corresponding receiver (Rx) at the other end. Although it may seem obvious, fiber optic polarity is a frequent source of confusion and installation errors. Let’s break down the essential basics for duplex applications.
November 12, 2025
Short-Reach Single-Mode Data Center Applications Put Reflectance on the Radar
Most of us understand that insertion loss is a critical parameter for fiber applications, especially in multimode applications with stringent loss budgets. While insertion loss has historically been less of a concern in long-reach single-mode applications, that’s no longer the case with short-reach single-mode applications, which have reduced loss budgets that also depend on reflectance.
October 15, 2025
Navigating Ultra-High-Density 400 and 800 Gig Networks in AI Data Center Environments
Artificial intelligence (AI) is rapidly transforming the data center. From training large language models (LLMs) like ChatGPT to delivering personalized content and predictive analysis, hyperscalers, cloud providers, and large enterprises are building high-performance computing (HPC) networks that leverage accelerated parallel processing to unlock AI's potential. Let's look at how these AI networks are deployed and the cable testing challenges they present.
October 6, 2025
Fiber Certification Testing: All You Really Need Is Loss, Length, Polarity (and Sometimes Reflectance)
As data rates increase to 400 Gig and beyond, and new fiber applications emerge, it’s easy to be confused about which fiber testing parameters are enough to guarantee support for high-speed applications. Other than for short-reach single-mode applications that are more susceptible to reflections and take connector reflectance into consideration, insertion loss testing, length, and polarity are really all you need for Tier 1 certification testing.
September 8, 2025
5 Reasons Every IT Pro Should Have a LinkIQ™ Tester in Their Toolkit
In a recent IT Trends 2024 Industry Report, 2,000+ IT pros say monitoring, troubleshooting, and Wi-Fi management are their top three network activities; 44% of them juggle ten or more network-related tools as they work. Let’s streamline those critical tasks! Here are five reasons why every IT pro should have a Fluke Networks LinkIQ™ Cable+Wi-Fi+Network Tester in their toolkit.
August 19, 2025
New Solutions for VSFF Applications
New very small form-factor (VSFF) connectors — MDC, CS, and SN duplex connectors and MMC multi-fiber connectors — are increasingly popular in high-density fiber applications like data centers. They must be properly tested, inspected, and cleaned to keep everything running smoothly. Whether you’re installing, reconfiguring, or troubleshooting, certain essential tools can make certifying link performance and inspecting for and eliminating contamination more efficient.
August 12, 2025
OTDR: Your Ultimate Troubleshooter
You're ready to use an optical loss test set (OLTS) for Tier 1 fiber certification. If some critical fiber links exceed the application’s loss budget, however, you’ll need to troubleshoot. An OLTS ensures the most accurate insertion loss measurement, but it can't pinpoint the exact location of the loss. Now an optical time domain reflectometer (OTDR) becomes your ultimate troubleshooting solution.
August 11, 2025
What Is PoE Negotiation?
First introduced in 2003, Power over Ethernet (PoE) has evolved to deliver up to 90 watts (W) of direct current (DC) power to a wide range of IP-based network devices, from clocks and phones to surveillance cameras, wireless access points, point-of-sale devices, and more. A negotiation process is required before any PoE power is delivered to a powered device (PD) from power sourcing equipment (PSE), such as a PoE network switch. Let’s take a closer look at how the PoE negotiation process happens and what you need to know when testing PoE systems.
June 30, 2025
Top 10 Cable Testing Mistakes to Avoid
The smart individuals who install, test, and certify network cabling plants understand the importance of meeting standards-based performance parameters and ensuring application support; yet even the best can make mistakes that can adversely impact both the bottom line and customer satisfaction. Here are the top 10 mistakes you should avoid when testing network cabling systems.
June 5, 2025
The Ultimate Guide to Network and Cable Testing
In today's digitally-driven world, ensuring the integrity and efficiency of network infrastructures — especially in high-density environments like data centers — is paramount, whether you're running a small business or responsible for a large-scale enterprise network.
May 29, 2025
