布线发展史
Short-Reach Single-Mode Puts Reflectance on the Radar
Most of us are well aware that insertion loss budgets have gotten tighter as we have moved from 10 to 40/100 Gig for multimode fiber applications. One would think that we can’t say the same for single-mode applications that have historically meant larger loss budgets – 6.3dB for 100 Gig over singlemode (100GBASE-LR4) versus just 1.9dB for 100 Gig over multimode (100GBASE-SR4). But that’s no longer the case with new short-reach single-mode applications.
2019 年 8 月 6 日
101 系列：以太网回到起点
It’s been more than 40 years since Bob Metcalfe published this simple diagram explaining his invention for interconnecting computers and printers at the Xerox Palo Alto Research Center in California. His patented multipoint data connection system with collision detection later became known as Ethernet.
2019 年 7 月 31 日
Know the Punch Line
Installers have been punching down copper twisted-pair cable for decades and still do so for terminating cables to IDC towers on jacks, patch panels and connecting blocks. While the practice hasn’t changed, punchdown tools have come a long way, and you now have some options at your fingertips. So how do you choose? Let’s take a closer look.
2019 年 7 月 23 日
AV over Twisted Pair: What Do I Need to Test For?
Whether it’s video conferencing or digital signage, many of you are likely facing requests from your customers to deploy cable plants that support audio-visual systems.
Many of these applications utilize twisted pair cabling, and technology advancements now make it possible to deliver power to video displays simultaneously with these video signals over the same cabling. When it comes to deploying and testing cable plants required to support these AV systems, it’s important to understand best testing practices to ensure your customers get the perfect picture they expect.
2019 年 7 月 17 日
Not Exactly in the Limelight – Yet
It’s been a while since we’ve talked about OM5 multimode fiber, and despite its lime green color and being added to the ANSI/TIA-568.3-D standard in 2016, it hasn’t exactly been in the limelightbut it looks like that won’t always be the case.
2019 年 7 月 10 日
Cabling Chronicles’ 4th of July Reflections
The 4th of July is always a time to reflect on our history, where we come from and the dedication of our founding fathers. But it’s also a time to look ahead, learn from past mistakes and progress towards a better future.
Our industry has a lot of history as well as traditional practices that we still use today simply because they work. But we also know that there are new ways of doing things, new parameters and new applications that are driving positive change.
2019 年 7 月 1 日
Channel, Permanent Link, Patch Cords, MPTL, E2E… Oh My!
With the addition of the modular plug terminated link (MPTL) configuration to the latest ANSI-TIA 568.2-D standard, and now end-to-end (E2E) configurations getting some attention in ISO/IEC standards (and likely soon TIA as well), you might be overwhelmed with the choices and be wondering what you’re supposed to test and when. Let’s take a look.
2019 年 6 月 26 日
Understanding insertion loss and loss budgets: Make or break an ICT career Digital Transformation and Industrial IoT age Part 3 of 3
Expert Profile: Vangie Michenzi, Senior Fiber Optic Project Manager, Advanced Communication Technology Services
Part 3 of a three-part series
In this day and age, with everyone preparing for the future of 5G, the internet of things, and industrial automation, if you’re a contractor or technician you better know and understand loss budgets!
2019 年 6 月 19 日
Getting Polarity Right the First (or Second) Time Around
While the fact that a fiber link’s transmit signal (Tx) must match the corresponding receiver (Rx) at the other end makes perfect sense, ensuring proper polarity to ensure that this correspondence is maintained continues to cause plenty of confusion – especially when it comes to multi-fiber MPO connectivity where 12 fibers located in Position 1 through 12 at one end must each arrive at their corresponding position at the other end.
2019 年 6 月 12 日
Disaster Due Diligence
If you’ve turned on the news in the past couple of months, or if you live anywhere in the southern or central U.S., you’re well aware that natural disasters are at an all-time high – from recent tornadoes that have stretched from Texas north to Minnesota and east to Pennsylvania, to the swelling Missouri, Mississippi, Arkansas and Ohio Rivers and their tributaries causing flooding in nearly two-thirds of the country. In fact, 2019 has already seen more than 1000 confirmed tornadoes (more than in all of 2018), and more than half happened in the month of May.
2019 年 6 月 6 日
