Categories (x) > Industrial (x)
Content Type (x) > Black Box Explains (x)

Results 1-10 of 62 1 2 3 4 5 > >> 

Black Box Explains... Pulling eyes and fiber cable.

Fiber optic cable can be damaged if pulled improperly. Broken or cracked fiber, for example, can result from pulling on the fiber core or jacket instead of the strength member.... more/see it nowAnd too much tension or stress on the jacket, as well as too tight of a bend radius, can damage the fiber core. If the cable’s core is harmed, the damage can be difficult to detect.

Once the cable is pulled successfully, damage can still occur during the termination phase. Field termination can be difficult and is often done incorrectly, resulting in poor transmission. One way to eliminate field termination is to pull preterminated cable. But this can damage the cable as well because the connectors can be knocked off during the pulling process. The terminated cable may also be too bulky to fit through ducts easily. To help solve all these problems, use preterminated fiber optic cable with a pulling eye. This works best for runs up to 2000 feet (609.6 m).

The pulling eye contains a connector and a flexible, multiweave mesh-fabric gripping tube. The latched connector is attached internally to the Kevlar®, which absorbs most of the pulling tension. Additionally, the pulling eye’s mesh grips the jacket over a wide surface area, distributing any remaining pulling tension and renders it harmless. The end of the gripping tube features one of three different types of pulling eyes: swivel, flexible, or breakaway.

Swivel eyes enable the cable to go around bends without getting tangled. They also prevent twists in the pull from being transferred to the cable. A flexible eye follows the line of the pull around corners and bends, but it’s less rigid. A breakaway eye offers a swivel function but breaks if the tension is too great. We recommend using the swivel-type pulling eye.

A pulling eye enables all the fibers to be preterminated to ensure better performance. The terminated fibers are staggered inside the gripping tube to minimize the diameter of the cable. This enables the cable to be pulled through the conduit more easily. collapse

Black Box Explains...How computer speeds are enhanced with PCI buses and UARTs.

The Peripheral Component Interconnect (PCI®) Bus enhances both speed and throughput. The PCI Local Bus is a high-performance bus that provides a processor-independent data path between the CPU and high-speed... more/see it nowperipherals. PCI is a robust interconnect interface designed specifically to accommodate multiple high-performance peripherals for graphics, full-motion video, SCSI, and LANs.

UARTs (Universal Asynchronous Receiver/ Transmitters) are integrated circuits that convert bytes from the computer bus into serial bits for transmission. By providing surplus memory in a buffer, UARTs help your applications overcome the factors that slow down your system. collapse

Black Box Explains...Category wiring standards

The ABCs of standards
There are two primary organizations dedicated to developing and setting structured cabling standards. In North America, standards are issued by the Telecommunications Industry Association (TIA),... more/see it nowwhich is accredited by the American National Standards Institute (ANSI). The TIA was formed in April 1988 after a merger with the Electronics Industry Association (EIA). That’s why its standards are commonly known as ANSI/TIA/EIA, TIA/EIA, or TIA.

Globally, the organizations that issue standards are the International Electrotechnical Commission (IEC) and the International Organization for Standardization (ISO). Standards are often listed as ISO/IEC. Other organizations include the Canadian Standards Association (CSA), CENELEC (European Committee for Electrotechnical Standardizations), and the Japanese Standards Association (JSA/JSI).

The committees of all these organizations work together and the performance requirements of the standards are very similar. But there is some confusion in terminology.

The TIA cabling components (cables, connecting hardware, and patch cords) are labeled with a ”category.” These components together form a permanent link or channel that is also called a ”category.” The ISO/IEC defines the link and channel requirements with a ”class” designation. But the components are called a ”category.”

The standards
Category 5 (CAT5) —ratified in 1991. It is no longer recognized for use in networking.

Category 5e (CAT5e), ISO/IEC 11801 Class D, ratified in 1999, is designed to support full-duplex, 4-pair transmission in 100-MHz applications. The CAT5e standard introduced the measurement for PS-NEXT, EL-FEXT, and PS-ELFEXT. CAT5e is no longer recognized for new installations. It is commonly used for 1-GbE installations.

Category 6 (CAT6) – Class E has a specified frequency of 250 MHz, significantly improved bandwidth capacity over CAT5e, and easily handles Gigabit Ethernet transmissions. CAT6 supports 1000BASE-T and, depending on the installation, 10GBASE-T (10-GbE).

10-GbE over CAT6 introduces Alien Crosstalk (ANEXT), the unwanted coupling of signals between adjacent pairs and cables. Because ANEXT in CAT6 10-GbE networks is so dependent on installation practices, TIA TSB-155-A and ISO/IEC 24750 qualifies 10-GbE over CAT6 over channels of 121 to 180 feet (37 to 55 meters) and requires it to be 100% tested, which is extremely time consuming. To mitigate ANEXT in CAT6, it is recommended that the cables be unbundled, that the space between cables be increased, and that non-adjacent patch panel ports be used. If CAT6 F/UTP cable is used, mitigation is not necessary and the length limits do not apply. CAT6 is not recommended for new 10-GbE installations.

Augmented Category 6 (CAT6A) –Class Ea was ratified in February 2008. This standard calls for 10-Gigabit Ethernet data transmission over a 4-pair copper cabling system up to 100 meters. CAT6A extends CAT6 electrical specifications from 250 MHz to 500 MHz. It introduces the ANEXT requirement. It also replaces the term Equal Level Far-End Crosstalk (ELFEXT) with Attenuation to Crosstalk Ratio, Far-End (ACRF) to mesh with ISO terminology. CAT6A provides improved insertion loss over CAT6. It is a good choice for noisy environments with lots of EMI. CAT6A is also well-suited for use with PoE+.

CAT6A UTP cable is significantly larger than CAT6 cable. It features larger conductors, usually 22 AWG, and is designed with more space between the pairs to minimize ANEXT. The outside diameter of CAT6A cable averages 0.29"–0.35" compared to 0.21"–0.24" for CAT6 cable. This reduces the number of cables you can fit in a conduit. At a 40% fill ratio, you can run three CAT6A cables in a 3/4" conduit vs. five CAT6 cables.

CAT6A UTP vs. F/UTP. Although shielded cable has the reputation of being bigger, bulkier, and more difficult to handle and install than unshielded cable, this is not the case with CAT6A F/UTP cable. It is actually easier to handle, requires less space to maintain proper bend radius, and uses smaller conduits, cable trays, and pathways. CAT6A UTP has a larger outside diameter than CAT6A F/UTP cable. This creates a great difference in the fill rate of cabling pathways. An increase in the outside diameter of 0.1", from 0.25" to 0.35" for example, represents a 21% increase in fill volume. In general, CAT6A F/UTP provides a minimum of 35% more fill capacity than CAT6A UTP. In addition, innovations in connector technology have made terminating CAT6A F/UTP actually easier than terminating bulkier CAT6A UTP.

Category 7 (CAT7) –Class F was published in 2002 by the ISO/IEC. It is not a TIA recognized standard and TIA plans to skip over it.

Category 7 specifies minimum performance standards for fully shielded cable (individually shielded pairs surrounded by an overall shield) transmitting data at rates up to 600 MHz. It comes with one of two connector styles: the standard RJ plug and a non-RJ-style plug and socket interface specified in IEC 61076-2-104:2.

Category 7a (CAT7a) –Class Fa (Amendment 1 and 2 to ISO/IEC 11801, 2nd Ed.) is a fully shielded cable that extends frequency from 600 MHz to 1000 MHz.

Category 8 – The TIA decided to skip Category 7 and 7A and go to Category 8. The TR-42.7 subcommittee is establishing specs for a 40-Gbps twisted-pair solution with a 2-GHz frequency. The proposed standard is for use in a two-point channel in a data center at 30 meters. It is expected to be ratified in February 2016. The TR-42.7 subcommittee is also incorporating ISO/IEC Class II cabling performance criteria into the standard. It is expected to be called TIA-568-C.2-1. The difference between Class I and Class II is that Class II allows for three different styles of connectors that are not compatible with one another or with the RJ-45 connector. Class I uses an RJ-45 connector and is backward compatible with components up to Category 6A. collapse

Black Box Explains...How fiber is insulated for use in harsh environments.

Fiber optic cable not only gives you immunity to interference and greater signal security, but it’s also constructed to insulate the fiber’s core from the stress associated with use in... more/see it nowharsh environments.

The core is a very delicate channel that’s used to transport data signals from an optical transmitter to an optical receiver. To help reinforce the core, absorb shock, and provide extra protection against cable bends, fiber cable contains a coating of acrylate plastic.

In an environment free from the stress of external forces such as temperature, bends, and splices, fiber optic cable can transmit light pulses with minimal attenuation. And although there will always be some attenuation from external forces and other conditions, there are two methods of cable construction to help isolate the core: loose-tube and tight-buffer construction.

In a loose-tube construction, the fiber core literally floats within a plastic gel-filled sleeve. Surrounded by this protective layer, the core is insulated from temperature extremes, as well as from damaging external forces such as cutting and crushing.

In a tight-core construction, the plastic extrusion method is used to apply a protective coating directly over the fiber coating. This helps the cable withstand even greater crushing forces. But while the tight-buffer design offers greater protection from core breakage, it’s more susceptible to stress from temperature variations. Conversely, while it’s more flexible than loose-tube cable, the tight-buffer design offers less protection from sharp bends or twists. collapse

Black Box Explains…Media converters that also work as switches.

Media converters transparently convert the incoming electrical signal from one cable type and then transmit it over another type—thick coax to Thin, UTP to fiber, and so on. Traditionally, media... more/see it nowconverters were purely Layer 1 devices that only converted electrical signals and physical media and didn’t do anything to the data coming through the link.

Today’s media converters, however, are often more advanced Layer 2 Ethernet devices that, like traditional media converters, provide Layer 1 electrical and physical conversion. But, unlike traditional media converters, they also provide Layer 2 services and route Ethernet packets based on MAC address. These media converters are often called media converter switches, switching media converters, or Layer 2 media converters. They enable you to have multiple connections rather than just one simple in-and-out connection. And because they’re switches, they increase network efficiency.

Media converters are often used to connect newer 100-Mbps, Gigabit Ethernet, or ATM equipment to existing networks, which are generally 10BASE-T, 100BASE-T, or a mixture of both. They can also be used in pairs to insert a fiber segment into copper networks to increase cabling distances and enhance immunity to electromagnetic interference.

Rent an apartment…
Media converters are available in standalone models that convert between two different media types and in chassis-based models that house many media converters in a a single chassis.

Standalone models convert between two media. But, like a small apartment, they can be outgrown.

Consider your current and future applications before selecting a media converter. A good way to anticipate future network requirements is to choose media converters that work as standalone devices but can be rackmounted if needed later.

…or buy a house.
Chassis-based or modular media converter systems are normally rackmountable and have slots to house media converter modules. Like a well-planned house, the chassis gives you room to grow. These are used when many Ethernet segments of different media types need to be connected in a central location. Modules are available for the same conversions performed by the standalone converters, and they enable you to mix different media types such as 10BASE-T, 100BASE-TX, 100BASE-FX, ATM, and Gigabit modules. Although enterprise-level chassis-based systems generally have modules that can only be used in a chassis, many midrange systems feature modules that can be used individually or in a chassis. collapse

Black Box Explains... GBICs

A Gigabit Interface Converter (GBIC) is a transceiver that converts digital electrical currents to optical signals and back again. GBICs support speeds of 1 Gbps or more and are typically... more/see it nowused as an interface between a high-speed Ethernet or ATM switch and a fiber backbone. GBICs are hot-swappable, so switches don’t need to be powered down for their installation. collapse

Black Box Explains...Choosing cabinets and racks.

Why cabinets? Why racks?

A cabinet is an enclosure with a door (or doors); a rack is an open frame. There are several things you... more/see it nowshould consider when you’re deciding whether you need an enclosed cabinet or a rack.

First, what equipment will you be putting in it? The extra stability of a cabinet might be important if you’re installing large, heavy equipment like servers. But if you need frequent access to all sides of the equipment, an open rack might be more convenient. And if your equipment needs a lot of ventilation, you’ll have to be more careful about the air supply if you enclose it in a cabinet.

Second, in what environment will you be installing it? If the environment is open or dusty, for example, you might need the extra protection of an enclosed cabinet. On the other hand, a rack might be perfectly adequate in a well-maintained data center.

Don’t neglect aesthetics. Will customers or clients see your installation? A cabinet with a door looks much neater than an open rack. When you’re trying to create a professional image, everything counts.

Finally, there’s security. An enclosed cabinet can be locked with a simple lock and key.

On the other hand, there are advantages to open racks, too. It’s easier to get at all sides of the equipment. But you’ll have to take other steps to keep the equipment secure-keeping it in a locked room, for example.

Both cabinets and racks come in all sizes and in many different installation styles. Some are freestanding; some are designed to be mounted on a wall. Others sit on the floor but attach to the wall for more stability.

If you need to set up your installation in a hurry, you can order a preassembled cabinet. You’re ready to load your equipment as soon as the cabinet arrives.

Choosing the right server cabinet.

Consider this quick checklist of features when choosing a server cabinet:

  • High-volume airflow. The requirements for additional airflow increase as more servers are mounted in a cabinet. Additionally, manufacturers are making servers narrower to increase available space. But with more servers in the same amount of space, heat buildup is frequently a problem.
  • Extra depth to accommodate newer, deeper servers.
  • Adjustable rails.
  • Rails with M6 square holes. Although 10-32 tapped and drilled holes are sometimes still required, newer hardware has M6 square holes. Know which type of mounting equipment you’ll need.
  • Front and/or rear accessibility.
NEMA 12 certification.

The National Electrical Manufacturers’ Association (NEMA) specifies guidelines for cabinet certifications. NEMA 12 cabinets are constructed for indoor use to provide protection against certain contaminants that might come in contact with the enclosed equipment. The NEMA 12 designation means a particular cabinet has met the guidelines, which include protection against falling dirt, circulating dust, lint, fibers, and dripping or splashing liquids. Protection against oil and coolant seepage is also a prerequisite for NEMA 12 certification.

Organizations with mission-critical equipment benefit from a NEMA 12 cabinet. Certain environments put equipment at a higher risk than others. For example, equipment in industrial plants is subject to varying degrees of extreme temperature. Even office buildings generate lots of dust and moisture, which is detrimental to equipment. NEMA 12 enclosures help to ensure that your operation suffers from as little downtime as possible.

Choosing the right rack.

Before you choose a rack, you have to determine what equipment you need to house. This list can include CPUs, monitors, keyboards, modems, servers, switches, hubs, routers, and UPSs. Consider the size and weight of all your equipment as well. The rack must be large and strong enough to hold everything you have now, and you’ll also want to leave extra room for growth.

Most racks are designed to hold equipment that’s 19" (48.3 cm) wide. But height and depth may vary from rack to rack. Common rack heights range from 39" (99.1 cm) to 87" (221 cm).

Another measurement you should know about is the rack unit. One rack unit, abbreviated as U, equals 1.75" (4.4 cm). A rack that is 20U, for example, has 20 rack spaces for equipment, or is 35" high (88.9 cm).

Understanding cabinet and rack measurements.

The main component of a cabinet or rack is a set of vertical rails with mounting holes to which you attach your equipment or shelves. When you consider the width or height of the rack, clarify whether they are inside or outside dimensions.

The first measurement you need to know is the width between the rails. The most common size is 19 inches with hole-to-hole centers measuring 18.3 inches. But there are also 23-inch and 24-inch cabinets and racks. Most rackmount equipment is made to fit 19-inch rails but can be adapted to fit wider rails.

After the width, the most important specification is the number of rack units, abbreviated “U.” It’s a measurement of vertical space available on the rails. Because the width is standard, the amount of vertical space is what determines how much equipment you can actually install. Remember that this measurement of usable vertical space is smaller than the external height of the cabinet or rack.

One rack unit (1U) is 1.75 inches of usable vertical space. So, for example, a rackmount device that’s 2U high will take up 3.5 inches of rack space. A rack that’s 20U high will have 35 inches of usable space.

Because both racks and the equipment that fit in them are usually measured in rack units, it’s easy to figure out how much equipment you can fit in a given cabinet or rack.

Do you need a fan?

Even if your cabinet or rack is in a climate-controlled room, the equipment in it can generate a lot of heat. You may want to consider adding a fan to help keep your equipment from overheating. It’s especially important to have adequate ventilation in an enclosed cabinet.

Getting power to your equipment.

Unless you want to live in a forest of extension cords, you’ll need one or more power strips. Some cabinets come with power strips built in.

If you need to order a power strip, consider which kind will be best for your installation. Rackmount power strips come in versions that mount either vertically or horizontally. Some have outlets that are spaced widely to accommodate transformer blocks-a useful feature if your equipment uses bulky power transformers.

Surge protection is another important issue. Some power strips have built-in surge protection; some don’t. With all the money you have invested in rackmount equipment, you’ll certainly want to make sure it’s protected.

Any mission-critical equipment should also be connected to an uninterruptible power supply (UPS). A UPS keeps your equipment from crashing during a brief blackout or brownout and gives you enough time to shut down everything properly in an extended power outage. You can choose a rackmount UPS for the most critical equipment, or you can plug the whole rack into a standalone UPS.

Managing the cables.

Your equipment may look very tidy when it’s neatly stacked in a cabinet. But you still have an opportunity to make a mess once you start connecting it all. Unless you’re very careful with your cables, you can create a rat’s nest you’ll never be able to sort out.

There are many cabinet and rack accessories that can simplify cable organization. We have Cable Management Guides, Rackmount Cable Raceways, Horizontal Covered Organizers, Vertical Cable Organizers, Horizontal Wire Ring Panels, and Cable Manager Hangers-all designed to help you manage your cables more easily.

Plotting your connections in advance helps you to decide how to organize the cables. Knowing where the connectors are on your equipment tells you where it’s most efficient to run cables horizontally and where it’s better to run them vertically.

The important thing is to have a plan. Most network problems are in the cabling, so if you let your cables get away from you now, you’re sure to pay for it down the road.

Asking for help.

When you’re setting up a cabinet or rack, you have a lot of different factors to consider. Black Box Tech Support is always happy to help you figure out what you need and how to put it together. For cabinets and racks solutions, call our Connectivity Group at 724-746-5500, press 1, 2, 2.


The difference between unmanaged, managed, and Web-smart switches

With regard to management options, the three primary classes of switches are unmanaged, managed, and Web smart. Which you choose depends largely on the size of your network and how... more/see it nowmuch control you need over that network.

Unmanaged switches are basic plug-and-play switches with no remote configuration, management, or monitoring options, although many can be locally monitored and configured via LED indicators and DIP switches. These inexpensive switches are typically used in small networks or to add temporary workgroups to larger networks.

Managed switches support Simple Network Management Protocol (SNMP) via embedded agents and have a command line interface (CLI) that can be accessed via serial console, Telnet, and Secure Shell. These switches can often be configured and managed as groups. More recent managed switches may also support a Web interface for management through a Web browser.

These high-end switches enable network managers to remotely access a wide range of capabilities including:

  • SNMP monitoring.
  • Enabling and disabling individual ports or port Auto MDI/MDI-X.
  • Port bandwidth and duplex control.
  • IP address management.
  • MAC address filtering.
  • Spanning Tree.
  • Port mirroring to monitor network traffic.
  • Prioritization of ports for quality of service (QoS).
  • VLAN settings.
  • 802.1X network access control.
  • IGMP snooping.
  • Link aggregation or trunking.

  • Managed switches, with their extensive management capabilities, are at home in large enterprise networks where network administrators need to monitor and control a large number of network devices. Managed switches support redundancy protocols for increased network availability.

    Web-smart switches—sometimes called smart switches or Web-managed switches—have become a popular option for mid-sized networks that require management. They offer access to switch management features such as port monitoring, link aggregation, and VPN through a simple Web interface via an embedded Web browser. What these switches generally do not have is SNMP management capabilities or a CLI. Web-smart switches must usually be managed individually rather than in groups.

    Although the management features found in a Web-smart switch are less extensive than those found in a fully managed switch, these switches are becoming smarter with many now offering many of the features of a fully managed switch. Like managed switches, they also support redundancy protocols for increased network availability.


    Black Box Explains...Media converters.

    Media converters interconnect different cable types such as twisted pair, fiber, and coax within an existing network. They are often used to connect newer Ethernet equipment to legacy cabling.... more/see it nowThey can also be used in pairs to insert a fiber segment into copper networks to increase cabling distances and enhance immunity to electromagnetic interference (EMI).

    Traditional media converters are purely Layer 1 devices that only convert electrical signals and physical media. They don’t do anything to the data coming through the link so they’re totally transparent to data. These converters have two ports—one port for each media type. Layer 1 media converters only operate at one speed and cannot, for instance, support both 10-Mbps and 100-Mbps Ethernet.

    Some media converters are more advanced Layer 2 Ethernet devices that, like traditional media converters, provide Layer 1 electrical and physical conversion. But, unlike traditional media converters, they also provide Layer 2 services—in other words, they’re really switches. This kind of media converter often has more than two ports, enabling you to, for instance, extend two or more copper links across a single fiber link. They also often feature autosensing ports on the copper side, making them useful for linking segments operating at different speeds.

    Media converters are available in standalone models that convert between two different media types and in chassis-based models that connect many different media types in a single housing.

    Rent an apartment

    Standalone converters convert between two media. But, like a small apartment, they can be outgrown. Consider your current and future applications before selecting a media converter. Standalone converters are available in many configurations, including 10BASE-T to multimode or single-mode fiber, 10BASE-T to Thin coax (ThinNet), 10BASE-T to thick coax (standard Ethernet), CDDI to FDDI, and Thin coax to fiber. 100BASE-T and 100BASE-FX models that connect UTP to single- or multimode fiber are also available. With the development of Gigabit Ethernet (1000 Mbps), media converters have been created to make the transition to high-speed networks easier.

    ...or buy a house.

    Chassis-based or modular media converters are normally rackmountable and have slots that house media converter modules. Like a well-planned house, the chassis gives you room to grow. These are used when many Ethernet segments of different media types need to be connected in a central location. Modules are available for the same conversions performed by the standalone converters, and 10BASE-T, 100BASE-TX, 100BASE-FX, and Gigabit modules may also be mixed.


    Black Box Explains...HDBaseT

    HDBaseT is a connectivity standard for distribution of uncompressed HD multimedia content. HDBaseT technology converges full HD digital video, audio, 100BaseT Ethernet, power over cable, and various control signals through... more/see it nowa single LAN cable. This is referred to as 5Play™, a feature set that sets HDBaseT technology above the current standard.

    HDBaseT delivers full HD/3D and 2K/4K uncompressed video to a network of devices or to a single device (point-to-point). HDBaseT supports all key HDMI 1.4 features, including EPG, Consumer Electronic Controls (CEC), EDID, and HDCP. The unique video coding scheme ensure the highest video quality at zero latency.

    As with the video, HDBaseT audio is passed through from the HDMI chipset. All standard formats are supported, including Dolby Digital, DTS, Dolby TrueHD, DTS HD-Master Audio.

    HDBaseT supports 100Mb Ethernet, which enables communications between electronic devices including televisions, sound systems, computers, and more. Additionally, Ethernet support enables access to any stored multimedia content (such as video or music streaming).

    HDBaseT's wide range of control options include CEC, RS-232, and infrared (IR). IP control is enabled through Ethernet channel support.

    The same cable that delivers video, audio, Ethernet, and control can deliver up to 100W of DC power. This means users can place equipment where one wants to, not just those locations with an available power source. HDBaseT Architecture
    HDBaseT sends video, audio, Ethernet, and control from the source to the display, but only transfers 100Mb of data from display to source (Ethernet and control data). The asymmetric nature of HDBaseT is based on a digital signal processing (DSP) engine and an application front end (AFE) architecture.

    HDBaseT uses a proprietary version of Pulse Amplitude Modulation (PAM) technology, where digital data is represented as a coding scheme using different levels of DC voltage at high rates. This special coding provides a better transfer quality to some kinds of data without the need to "pay" the protecting overhead for the video content, which consumes most of the bandwidth. HDBaseT PAM technology enables the 5Play feature-set to be maintained over a single 330-foot (100 m) CAT cable without the electrical characteristics of the wire affecting performance.


    Results 1-10 of 62 1 2 3 4 5 > >> 


    Delivering superior technical support is our highest priority. Depending on the products or services we provide for you, please visit your appropriate support area.


    You have added this item to your cart.

    Important message about your cart:

    You requested more of "" than the currently available. The quantity has been changed to them maximum quantity available. View your cart.

    Black Box 1-800-316-7107 Black Box Network Services