An Inside (and Outside) Look at Fiber Active Optical Cables

September 5, 2019 at 8:00 AM


We’ve talked about Active Optical Cables (AOC) and their ability to use the same electrical inputs as traditional cables, but with optical fibers between the connectors. They deliver faster speeds and distance performance compared to copper cables while maintaining compatibility with standard electrical interfaces. We’ve delved into their use in the realm of USB and the benefits they bring. Now, we’re going to take a closer look at fiber AOCs and all they have to offer.


AOCs are opto-electronic devices used in place of standard fiber optic transceivers due to ease of deployment and lower cost compared to using individual transceivers with separable fiber optic cable assemblies.  The basic concept of a fiber AOC is to embed active optical transceivers into the assembly, as opposed to using separate pluggable fiber optical transceivers and standard, connectorized fiber cables.


Mainly invented to replace copper cabling in data centers and high performance computing applications, AOCs and their list of benefits can make older technologies seem obsolete. They have longer reach, higher bandwidth handling capabilities and provide secure, reliable transmissions. AOCs also limit EMI/RFI and provide low bit-error rates. Plus, AOC assemblies are smaller and lighter than copper cables, making the datacenter physically easier to manage.


AOCs are ideal for short-range, multi-lane data communication and interconnect applications. These assemblies support a range of protocols including Ethernet, InfiniBand and Fibre Channel. They can be used rack-to-rack, on optical backplanes, for storage, hubs, routers, servers, switches and more.


With all of these benefits, AOC assemblies might seem too good to be true, but they’re real and we’ve got an extensive line available with same-day shipping, check them out here.


802.3bz Provides Congestion Relief – 2.5 Gbps & 5 Gbps Over Copper

May 3, 2018 at 8:00 AM


Cat5e and Cat6 cables are two of the most widely used cables in the world. Traditionally, for conventional Cat5e and Cat6 twisted-pair copper cabling, Gigabit Ethernet (1 Gbps) is the fastest standard. A wired connection of 1 Gbps is probably enough speed for one PC user, but with the surge of high-speed Wi-Fi devices being used over the last few years, Gigabit Ethernet has become increasingly congested. Thus, the IEEE has developed the 802.3bz standard to ease the pain of 1 Gbps traffic and allow speeds of up to 2.5 Gbps and 5 Gbps over Cat5e and Cat6 copper cables.


To escape the 1 Gbps bottleneck and increase speeds to 10 Gbps, a network cable upgrade to Cat6a or Cat7 is usually required. At an estimated $300 per cable pull, upgrading cable is a costly process and not always feasible, especially for large networks which could also encounter expensive delays and connection disruptions in the process.  Fortunately, the 802.3bz allows users to avoid expensive cable upgrades. This new 2.5G/5GBASE-T standard can provide 2.5 Gbps speeds over 100 meters of Cat5e cable and 5 Gbps speeds over 100 meters of Cat6 cable. These higher speeds are bookended by a switch on one end and either an Ethernet extender or electronic device on the opposite end.


The physical layer of 2.5G/5GBASE-T is similar to 10GBASE-T, but uses 200 MHz or 100 MHz spectral bandwidth instead of 400 MHz. This is beneficial because 2.5G/5GBASE-T consumes less than half the bandwidth of 10GBASE-T and doesn’t require a high-quality, mega-shielded cable. The 802.3bz standard also provides additional features such as Power over Ethernet (PoE), which is useful when rolling out Wi-Fi access points.


With a growing need for faster connections, 802.3bz provides a sensible way to upgrade networking capabilities without the expense of re-cabling, all while improving user experience and avoiding costly downtime.


Counterfeit Cables 101

September 7, 2017 at 8:00 AM


Have you ever wondered how some cables are able to be sold at such dramatically low prices? In some cases, it’s because the cables aren’t exactly what they appear to be. Counterfeit cables are more common than you might think.  In fact, we found that cables can be counterfeit from both large and small manufacturers and domestic or overseas sources.


A counterfeit cable is any cable that is sold under false pretenses, where the cable specification doesn’t match the actual product construction. Implying that a cable meets a certain performance standard when it doesn’t, such as Cat6a, is also considered counterfeiting. In most cases, the cables are made with inferior materials so they can be offered at a cheaper price.


One major factor in avoiding counterfeit cables is ensuring that your supplier or manufacturer is consistently checking cable assemblies, proving UL compliance, testing cables and ensuring standards are met.


Here are some things you should be aware of to avoid getting stuck with counterfeit cables:

·  Substituting steel or aluminum for pure copper conductors – This cost saving method also causes the signal strength to drop below noise and cross-talk levels which will lead to problems in a high-speed network.


·  Cable jacket material – If a jacket is CMP or CMR-rated, a legitimate business will offer a signed Certificate of Conformance (CoC) for their products. If there’s no CoC offered, the jacket might not meet rating standards.


·  Selective electrical performance testing – Some manufacturers claim their products were “fluke tested” but don’t run the full patch testing because it’s not easy to pass and it’s more expensive. Legitimate manufacturers will run the full performance testing to ensure their cable meets standards and provide you with the test result documentation.


·  Misleading cable markings – Cables sold in the U.S. have a variety of markings that can be used to look them up on the UL’s database, but that doesn’t always guarantee that the cable is worthy of its markings. A signed CoC is the best way to make sure that you’re not getting a counterfeit cable.


·  Deceiving connector construction – Using cheaper materials will lower the combustion rating for a plastic connector and cause metal connectors to eventually corrode and fail when mated.


·  Wire gauge changes – 25 AWG and 26 AWG cables are often mislabeled as 24 AWG. They best way to test the gauge is to request a sample, cut it open, remove the insulation and measure the conductors.


·  The Golden Sample – Manufacturers may create a golden sample to send to the customer, but cut corners when manufacturing the rest of the order to save money. Creating a quality control system to test the cables in each shipment, unbeknownst to the manufacturer, is your best bet to test for consistency in quality.


Cat6a - Taking Copper to the Next Level

July 28, 2016 at 8:00 AM


Copper cable has many advantages including flexibility, cost savings, and Power over Ethernet support– and now it can add lightning fast speeds to its list of attributes. Until recently, fiber cabling was the only way to achieve 10 Gigabit Ethernet data rates, but now Cat6a is taking copper to the next level with super-speed 10Gbps transmissions.


Cat6a cables can reach 10 Gigabit Ethernet speeds at frequencies of up to 500 MHz over low-cost copper cable. That makes Cat6a ten times faster than Cat6 and cheaper than fiber cabling. Cat6a is a high performance, cost-effective solution for moving large volumes of voice, video and data traffic over a network.  Its accelerated performance is perfect for use in data centers and storage area networks (SAN) that sometimes need to move terabits of data.


In addition to being fast, Cat6a supports longer distances than Cat6 with capabilities of up to 100 meters for 10GBASE-T. Cat6a cables are also backward-compatible with existing network infrastructure products, making for an easier migration path. Additionally, Cat6a cables are shielded which enhances overall performance and makes them more resistant to noise, interference and alien crosstalk.


With off the chart performance characteristics, Cat6a cables, couplers and other infrastructure products can take your network to the next level.


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