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  • Identify Types of Network Cables and Connectors

    There are three types of network cables: fiber, twisted pair, and coaxial.

    Fiber is the most expensive of the three and can run the longest distance. A number of types of connectors can work with fiber, but three you must know are SC, ST, and LC.

    Twisted pair is commonly used in office settings to connect workstations to hubs or switches. It comes in two varicties: unshielded (UTP) and shielded (STP), The two types of connectors commonly used are RJ-11 (four wires and popular with telephones), and RJ-45 (eight wires and used with xBaseT networks—100BaseT, 1000BaseT, and so forth). Two common wiring standards are T568A and T568B.

    Coaxial cabling is not as popular as it once was, but it's still used with cable television and some legacy networks. The two most regularly used connectors are F-conectors (television cabling) and BNC (10Base2, and so on).

    Fiber

    Fiber-optic cabling is the most expensive type. Although it's an excellent medium, it's often not used because of the cost of implementing it. It has a glass core within a rubber outer coating and uses beams of light rather than electrical signals to relay data. Because light doesn't diminish over distance the way electrical signals do, this cabling can run for distances measured in kilometers with transmission speeds from 100 Mbps up to 1 Gbps higher.

    Fiber optic cable

    Often, fiber is used to connect runs to wiring closets where they break out into UTP or other cabling types, or as other types of backbones. Fiber-optic cable can use either ST, SC, or LC connector. ST is a barrel-shaped connector, whereas SC is squared and easier to connect in small spaces.The LC connector looks similar to SC but adds a flange on the top (much like an RJ-45 connector) to keep it securely connected.

    st sc lc connectors

    Note: In addition to these listed in the A + objectives, other connectors are used with fiber. FC connectors may also be used but are not as common. MT-RJ is a popular connector for two fibers in a small form factor.

    Twisted Pair

    There are two primary types of twisted-pair cabling (with categories beneath cach that are shielded twisted pair (STP) and unshielded twisted pair (UTP). In both cases, the cabling is made up of pairs of wires twisted around each other.

    UTP offers no shielding (hence the name) and is the network cabling type most prone to outside interference. The interference can be from a fluorescent light ballast, eletrical motor, or other such source (known as eletromagnetic interference [EMI]) or from wires being too close together and signals jumping across them (known as crosstalk), STP adds a foil shield around the twisted wires to protect against EMI.

    Twisted Pair

    STP cable uses IBM data connector (IDC) or universal data connector (UDC) ends and connects to token ring networks. While you need to know STP for the exam, you are not required to have any knowledge of the connectors associated with it. You must, however, know that most UTP cable uses RJ-45 connectors, which look like telephone connectors (RJ-11) but have eight wires instead of four.

    RJ-45 connectors

    Two wiring standards are commonly used with twisted-pair cabling:T568A and T568B (sometimes referred to simply as 568A and 568B). These are telecommunications standards from TIA and EIA that specify the pin arrangements for the RJ-45 connectors on UTP or STP cables. The number 568 refers to the order in which the wires within the Category 5 cable are terminated and attached to the connector. The signal is identical for both.

    T568A was the first standard, released in 1991. Ten years later, in 2001, T568B was released. Pin numbers are read left to right, with the connector tab facing down. Notice that the pin-outs stay the same, and the only difference is in the color coding of the wiring.

     

    Pin assignments for T568A and T568B

    Note: Mixing cables can cause communication problems on the network. Before installing a network or adding a new component to it, make sure the cable being used is in the correct wiring standard.

    Coaxial

    Coaxial cable, or coax, is one of the oldest media used in networks. Coax is built around a center conductor or core that is used to carry data from point to point. The center conductor has an insulator wrapped around it, a shield over the insulator, and a nonconductive sheath around the shielding. This construction allows the conducting core to be relatively free from outside interference. The shielding also prevents the conducting core from emanating signals externally from the cable.

    Note: Before you read any further, accept the fact that the odds are incredibly slim that you will ever need to know about coax for a new installation in the real world (with the possible exception of RG-6, which is used from the wall to cable modem). If you do come across it, it will be in an existing installation and one of the first things you'll recommend is that it be changed. 

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  • Feds get huge response to request for IoT input

    By Sean Kinney   www.industrialiot5G.com

     

     

    More than 100 companies suggest ways U.S. government can help advance the IoT

    Many industry watchers feel the U.S. is slipping behind other countries, particularly Germany and China, in creating a unified national strategy for development of the Internet of Things or IoT. But federal leaders, in the early stages of involvement, reached out to the telecom industry for guidance.

    Back in April the National Telecommunications and Information Administration, a part of the U.S. Department of Commerce, issued a “request for comments on the benefits, challenges and potential roles for the government in fostering the advancement of the Internet of Things.”

    Two months later and the call for comment has been met in spades with more than 130 filings coming from a broad swath of telecom interests including carriers like AT&T, T-Mobile, Verizon and Vodafone; vendors including Nokia, Ericsson, Huawei and Samsung; and industry trade groups like the Wi-Fi Alliance, Wireless Infrastructure Association, the Open Connectivity Foundation and the GSMA.

    Here’s a full list of the respondents and their filings with NTIA. A review of some of the filings indicates a strong industry expectation that the rapid uptake of IoT will require global coordination and will likely create new markets while disrupting existing ones.

    Verizon representatives told NTIA: “To support this explosion of IoT devices, a robust and secure underlying communications network must serve as a foundation. That network requires both increased commercial spectrum and development of the underlying core infrastructure. We encourage all stakeholders to work together to ensure that these necessary building blocks for IoT development are available and accessible. To enable sufficient spectrum to power this new wave of connected innovation, private and public sectors must continue to cooperate, not only to develop more ways to effectively share spectrum, but also to provide federal users incentives to free up spectrum for commercial licensed and unlicensed use. As potentially billions of new IoT devices are deployed, they will drive data growth that – combined with the parallel growth in overall data usage by consumer devices – will require new commercial spectrum allocations to accommodate the unprecedented demands for more bandwidth. This includes spectrum necessary to support 5G, since 5G’s super-fast speeds and low latency will help facilitate new IoT use cases.”

    Ericsson commented: “In Ericsson’s view, 5G is the technology that will unleash the true potential of the Internet of Things. To support the IoT’s development, the government should unleash the resources that will ensure U.S. leadership in 5G by releasing more spectrum for commercial use. Through network slicing, 5G technology will allow a single infrastructure to meet the very different needs of Massive and Critical IoT devices – it will enable networks to handle the incredible increase in data from the billions of low energy, low data devices, while also providing very high reliability, availability and security for critical uses. We also encourage the government to support global standards and best practices and to allow industry to continue to innovate and coalesce around the most favorable IoT solutions.”

    And from the GSMA’s point of view: “The United States should forbear from regulating IoT and avoid reflexively extending legacy regulations designed for outdated technologies to the IoT…The U.S. government should support and promote industry alignment around interoperable, industry-led specifications and standards across the global IoT ecosystem…The U.S. government should promote the allocation of globally harmonized spectrum that can support IoT…The U.S. government should encourage industry to build trust into IoT devices. Existing laws and regulations, operating in tandem with self-regulatory regimes and best practices, will provide sufficient protection to consumers as the IoT develops…Finally, the U.S. government should engage on a bilateral and multilateral basis, as appropriate, to ensure that international IoT activities similarly encourage competition, investment, and innovation. Regulatory interference at this stage—from any source—could lead to fragmentation and impede innovation, inhibiting the IoT’s ability to reach its full potential to deliver benefits to consumers.”

     

     

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  • Atari bringing back devices with Sigfox IoT agreement

    By Tim Skinner           Telecoms.com

    Retro gaming giant Atari will soon be entering the IoT arena following a partnership with Sigfox, the low power WAN provider. Famed for its trailblazing old-school computers and gaming consoles in the 1980s and 1990s, an announcement from Atari said it will soon be developing and launching consumer IoT services. While tangible details weren’t particularly forthcoming, and won’t be for the time being, Atari did hint at a move back to hardware having been primarily, if not solely, focused on software and gaming for the best part of the last 20 years. Atari said the initial product line will include offerings in areas such as home, pets, lifestyle and safety. By combining with Sigfox, Atari plans on developing a wide range of new products, from the very simple to the highly sophisticated, which users can track at any time. Sigfox says that by connecting to its network, products will benefit from an extended battery life and no need for paring or connectivity configuration. “By partnering together and using SIGFOX’s dedicated IoT connectivity, we are going to create amazing products with our brand,” said Fred Chesnais, Chief Executive Officer, Atari. “We look forward to our collaboration with SIGFOX and releasing new products to the mass market on a global scale.” It’s fair to assume Atari is targeting a move back into hardware and away from gaming, although more information will be released in due course. Atari says development of the new product line will begin in 2016.

     

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  • How to Install or Remove SFP Transceiver Modules on Cisco Device

    The SFP (small form Factor pluggables) transceiver modules are hot-pluggable I/O devices that plug into module sockets. The transceiver connects the electrical circuitry of the module with the optical or copper network. SFP transceiver modules are the key components in today's transmission network. Thus, it is necessary to master the skill of installing or removing a transceiver modules to avoid unnecessary loss. This tutorial are going to guide you how to install or remove SFP transceiver module in a right way.

     

    Things you should Know Before Installing or Removing SFP

    Before removing or installing a Transceiver Module you must disconnect all cables, because of leaving these attached will damage the cables, connectors, and the optical interfaces. At the same time please be aware that do not often remove and install an SFP transceiver and it can shorten its useful life. For this reason transceivers should not be removed or inserted more often than is required. Furthermore, transceiver modules are sensitive to static, so always ensure that you use an ESD wrist strap or comparable grounding device during both installation and removal.

     

    Required Tools

    You will need these tools to install the SFP transceiver module:
    Wrist strap or other personal grounding device to prevent ESD occurrences.Antistatic mat or antistatic foam to set the transceiver on.Fiber-optic end-face cleaning tools and inspection equipment

     

    Installing SFP Transceiver Modules

    SFP transceiver modules can have three types of latching devices to secure an SFP transceiver in a port socket:
    SFP transceiver with a Mylar tab latch.SFP transceiver with an actuator button latch.SFP transceiver that has a bale-clasp latch.
    Types of SFP Latching

    Determine which type of latch your SFP transceiver uses before following the installation and removal procedures.

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  • Fiber Optic Overview

    Fiber Optic Communication - The Future Of Networking & Data Transmission

    Fiber optic communication is a method of transmitting information from one place to another by sending pulses of light through an optical fiber. The light forms an electromagnetic carrier wave that is modulated to carry information.

    First developed in the 1970s, fiber-optic communication systems have revolutionized the telecommunications industry and have played a major role in the advent of the Information Age. Because of its advantages over electrical transmission, optical fibers have largely replaced copper wire communications in core networks. Optical fiber is used by many telecommunications companies to transmit telephone signals, Internet communication, and cable television signals. Researchers have reached internet speeds of over 100 petabits per second using fiber-optic communication.

    Fiber's advantages has led to its use as the backbone of all of today's communications, telecom, Internet, CATV, etc. - even wireless, where towers are connected on fiber and antennas are using fiber up the towers.

    Fiber Communication Example

     

    Optical Fiber - The Better Solution

    Fiber vs. Copper. Fiber is the better solution!

    This photo from the infancy of fiber optics (to the right) was used to illustrate that one tiny optical fiber could carry more communications signals than a giant copper cable. Today one single mode fiber could carry the same amount of communications as 1000 of those old copper cables!

    Fiber offers thousands of times more bandwidth than copper cables and can go more than 1000 times further before needing repeaters - both of which contribute to the immense economic advantage of fiber optics over copper. You can do a similar analysis for using wireless transmission also, but wireless is limited by the available wireless spectrum which is overcrowded because of everyone's desire to use more mobile devices.

    Why Convert From Copper Cable To Fiber Optic Cable?

    If you need some convincing before you make your first fiber optic cable purchase keep the following facts in mind.

    CheckOptical Fiber - Much More Efficient & Secure

    Fiber optic cable operates much more efficiently and is more secure than traditional copper cabling. Fiber can transmit far more information over greater distance and with a higher clarity while offering a more secure connection. Fiber optic cable is resistant to electromagnetic interference and generates no radiation of its own. This point is important in locations where high levels of security must be maintained. Copper wire radiates energy that can be monitored. In contrast, taps in  Fiber optic cable  Fiber  are easily detected. Copper cable, is also subject to problems with attenuation, capacitance, and crosstalk.

    CheckOptical Fiber - Does Not Require Grounding

    Since fiber is made of glass, which is a bad electrical conductor, it does not require grounding and shields itself from other electrical interference. Fiber cables can be run near electrical cables without fear that it will weaken or interrupt the signal.

    CheckOptical Fiber - Corrosion Resistant

    Fiber optic cable does not corrode and is not as sensitive to water or chemicals. This means you can safely run fiber cable in direct contact with dirt or in close proximity to chemicals (with the proper outer jacket materials).

    CheckOptical Fiber - The Safer Choice

    Since fiber is not a good conductor of electricity, an installer or user will be safe from electrocution if there is a break in the outer jacket and the fiber is exposed.

     

    How Fiber Optic Communication Works

    The process of communicating using fiber-optics involves the following basic steps: Creating the optical signal involving the use of a transmitter, relaying the signal along the fiber, ensuring that the signal does not become too distorted or weak, receiving the optical signal, and converting it into an electrical signal.

    Fiber (or fibre) consists of a strand of pure glass a little larger than a human hair. Fiber optic cable employs photons and pulsing laser light for the transmission of digital signals. Photons pass through the glass with negligible resistance. As light passes through the cable, its rays bounce off the cladding in different ways as shown below. The optic core of fiber optic cable is pure silicon dioxide. The electronic 1s and 0s of computers are converted to optically coded 1s and 0s. A light-emitting diode on one end of the cable then flashes those signals down the cable. At the other end, a simple photodetector collects the light and converts it back to electrical signals for transmission over copper cable networks.

    Fiber light source and transmission illustartion.

    Step index multimode was the first fiber design but is too slow for most uses, due to the dispersion caused by the different path lengths of the various modes. Step index fiber is rare - only POF uses a step index design today.

    Graded index multimode fiber uses variations in the composition of the glass in the core to compensate for the different path lengths of the modes. It offers hundreds of times more bandwidth than step index fiber - up to about 2 gigahertz.

    Singlemode fiber shrinks the core down so small that the light can only travel in one ray. This increases the bandwidth to almost infinity - but it's practically limited to about 100,000 gigahertz - that's still a lot!

     

    Optic Fiber Cable Construction

    Optic Fiber Cable Structure.

     

    Optical fiber consists of a core and a cladding layer, selected for total internal reflection due to the difference in the refractive index between the two. In practical fibers, the cladding is usually coated with a layer of acrylate polymer or polyimide. This coating protects the fiber from damage but does not contribute to its optical waveguide properties.

    Individual coated fibers (or fibers formed into ribbons or bundles) then have a tough resin buffer layer and/or core tube(s) extruded around them to form the cable core. Several layers of protective sheathing, depending on the application, are added to form the cable.

    Rigid fiber assemblies sometimes put light-absorbing ("dark") glass between the fibers, to prevent light that leaks out of one fiber from entering another. This reduces cross-talk between the fibers, or reduces flare in fiber bundle imaging applications.

    A “dopant” is added to the core to actually make it less pure than the cladding. This changes the way the core transmits light. Because the cladding has different light properties than the core, it tends to keep the light within the core. Because of these properties, fiber optic cable can be bent around corners and can be extended over distances of up to 100 miles.

    A typical laser transmitter can be pulsed billions of times per second. In addition, a single strand of glass can carry light in a number of wavelengths (colors), meaning that the data-carrying capacity of fiber optic cable is potentially thousands of times greater than copper cable.

     

    Types Of Fiber Optic Cable

    • Plastic cable, which works only over a few meters, is inexpensive and works with inexpensive components.
    • Plastic-coated silica cable offers better performance than plastic cable at a little more cost.
    • Single-index monomode fiber cable is used to span extremely long distances. The core is small and provides high bandwidth at long distances. Lasers are used to generate the light signal for single-mode cable. This cable is the most expensive and hardest to handle, but it has the highest bandwidths and distance ratings.
    • Step-Index multimode cable has a relatively large diameter core with high dispersion characteristics. The cable is designed for the LAN environment and light is typically generated with a LED (light-emitting diode).
    • Graded-index multimode cable has multiple layers of glass that contain dispersions enough to provide increases in cable distances.

    Cable specifications list the core and cladding diameters as fractional numbers. For example, the minimum recommended cable type for FDDI (Fiber Distributed Data Interface) is 62.5/125 micron multimode fiber optic cable.That means the core is 62.5 microns and the core with surrounding cladding is a total of 125 microns.

    • The core specifications for step-index and graded-index multimode cables range from 50 to 1,000 microns.
    • The cladding diameter for step mode cables ranges from 125 to 1,050 microns.
    • The core diameter for single-mode step cable is 4 to 10 microns, and the cladding diameter is from 75 to 125 microns.
    Choosing the right Optic Fiber Glass Type/ Fiber Mode.

     

    Indoor Vs. Outdoor Optic Fiber Cable Applications

    For  indoor applications, the jacketed fiber is generally enclosed, with a bundle of flexible fibrous polymer strength members like aramid (e.g. Twaron or Kevlar), in a lightweight plastic cover to form a simple cable. Each end of the cable may be terminated with a specialized optical fiber connector to allow it to be easily connected and disconnected from transmitting and receiving equipment.

    For outdoor applications or use in more strenuous environments, a much more robust cable construction is required. In loose-tube construction the fiber is laid helically into semi-rigid tubes, allowing the cable to stretch without stretching the fiber itself. This protects the fiber from tension during laying and due to temperature changes. Loose-tube fiber may be "dry block" or gel-filled. Dry block offers less protection to the fibers than gel-filled, but costs considerably less. Instead of a loose tube, the fiber may be embedded in a heavy polymer jacket, commonly called "tight buffer" construction. Tight buffer cables are offered for a variety of applications, but the two most common are "Breakout" and "Distribution".

    Breakout Cables normally contain a ripcord, two non-conductive dielectric strengthening members (normally a glass rod epoxy), an aramid yarn, and 3 mm buffer tubing with an additional layer of Kevlar surrounding each fiber. The ripcord is a parallel cord of strong yarn that is situated under the jacket(s) of the cable for jacket removal. Distribution Cables  have an overall Kevlar wrapping, a ripcord, and a 900 micrometer buffer coating surrounding each fiber. These fiber units are commonly bundled with additional steel strength members, again with a helical twist to allow for stretching.

    A critical concern in outdoor cabling is to protect the fiber from contamination by water. This is accomplished by use of solid barriers such as copper tubes, and water-repellent jelly or water-absorbing powder surrounding the fiber.

    Finally, the cable may be armored to protect it from environmental hazards, such as construction work or gnawing animals. Undersea cables are more heavily armored in their near-shore portions to protect them from boat anchors, fishing gear, and even sharks, which may be attracted to the electrical power that is carried to power amplifiers or repeaters in the cable.

    Modern cables come in a wide variety of sheathings and armor, designed for applications such as direct burial in trenches, dual use as power lines, installation in conduit, lashing to aerial telephone poles, submarine installation, and insertion in paved streets.

    To purchase your fiber cables, please click link below:

    Fiber Patch Cables

     

     

     

     

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