Black Box Explains...USB 2.0 and USB OTG.
The Universal Serial Bus (USB) hardware (plug-and-play) standard makes connecting peripherals to your computer easy.
USB 1.1, introduced in 1995, is the original USB standard. It has two data rates:... more/see it now12 Mbps for devices such as disk drives that need high-speed throughput and 1.5 Mbps for devices such as joysticks that need much lower bandwidth.
In 2002, a newer specification, USB 2.0, or Hi-Speed USB 2.0, gained wide acceptance in the industry. This version is both forward- and backward-compatible with USB 1.1. It increases the speed of the peripheral to PC connection from 12 Mbps to 480 Mbps, or 40 times faster than USB 1.1!
This increase in bandwidth enhances the use of external peripherals that require high throughput, such as CD/DVD burners, scanners, digital cameras, video equipment, and more. USB 2.0 supports demanding applications, such as Web publishing, in which multiple high-speed devices run simultaneously. USB 2.0 also supports Windows® XP through a Windows update.
An even newer USB standard, USB On-The-Go (OTG), is also in development. USB OTG enables devices other than a PC to act as a host. It enables portable equipment—such as PDAs, cell phones, digital cameras, and digital music players—to connect to each other without the need for a PC host.
USB 2.0 specifies three types of connectors: the A connector, the B connector, and the Mini B connector. A fourth type of connector, the Mini A (used for smaller peripherals such as mobile phones), was developed as part of the USB OTG specification. collapse
Black Box Explains...Choosing SCSI cables.
1. Quality. Your systems performance depends on the quality of your SCSI cables. Without high-quality cables specifically designed for SCSI applications, you could be jeopardizing your SCSI lifeline. Inferior cables,... more/see it nowadapters, and terminators can cause random errors, data corruption, or even a system crash! Black Box® SCSI Cables and components are the absolute best-quality products. And theyre guaranteed for life.
2. Length. For peak network performance, make sure your cables are the right length. As cable runs get longer, signals weaken and are more susceptible to noise. Always use the shortest cable for the task. And stay within the SCSI-1 and SCSI-2 standards of six meters or three meters for Fast SCSI. Remember, this is the total length of the bus, including all internal and external cables. collapse
Black Box Explains...Super Dynamic II.
This proprietary processing technology developed by Panasonic® eliminates backlighting problems commonly seen with security camera systems. It gives you clear images regardless of the lighting situation and a dynamic range... more/see it nowthats 64 times greater than that offered by conventional video cameras.
Super Dynamic II accomplishes this by using a double-speed, charge-coupled device (CCD). It takes two pictures in the time
it takes for a conventional CCD to capture one. The first Super Dynamic II picture is a long exposure (1⁄60th of a second) that captures a scenes dark areas; the second is a short exposure (from 1⁄1000th to 1⁄4000th of a second) that captures the scenes bright areas. Super Dynamic II then combines the best quality signals from the two images and outputs them as a Composite analog image.
The technologys enhanced Digital Signal Processing (DSP) circuitry corrects gradation to give you proper black level references so black areas within a scene appear blacknot washed-out shades of gray. It also enables images with high contrast to be seen on the screen.
Whats more, Super Dynamic II technology provides exceptional sensitivity (0.8 lux using an F1.4 lens), enabling the camera to capture vivid details and color even in low-light applications. collapse
Black Box Explains...SFP, SFP+, and XFP transceivers.
SFP, SFP+, and XFP are all terms for a type of transceiver that
plugs into a special port on a switch or other network device to convert the port to... more/see it nowa copper or fiber interface. These compact transceivers replace the older, bulkier GBIC interface. Although these devices are available in copper, their most common use is to add fiber ports. Fiber options include multimode and single-mode fiber in a variety of wavelengths covering distances of up to 120 kilometers (about 75 miles), as well as WDM fiber, which uses two separate wavelengths to both send and receive data on a
single fiber strand.
SFPs support speeds up to 4.25 Gbps and are generally used for Fast Ethernet or Gigabit Ethernet applications. The expanded SFP
standard, SFP+, supports speeds of 10 Gbps or higher over fiber. XFP
is a separate standard that also supports 10-Gbps speeds. The primary difference between SFP+ and the slightly older XFP standard is that SFP+ moves the chip for clock and data recovery into a line card on the host device. This makes an SFP+ smaller than an XFP, enabling greater port density.
Because all these compact transcievers are hot-swappable, there’s no need to shut down a switch to swap out a module—it’s easy to change interfaces on the fly for upgrades and maintenance.
Another characteristic shared by this group of transcievers is that they’re OSI Layer 1 devices—they’re transparent to data and do not examine or alter data in any way. Although they’re primarily used with Ethernet, they’re also compatible with uncommon or legacy standards such as Fibre Channel, ATM, SONET, or Token Ring.
Formats for SFP, SFP+, and XFP transceivers have been standardized by multisource agreements (MSAs) between manufacturers, so
physical dimensions, connectors, and signaling are consistent and
interchangeable. Be aware though that some major manufacturers, notably Cisco, sell network devices with slots that lock out transceivers from other vendors.
Black Box Explains: M1 connectors.
In 2001, the Video Electronics Standards Association (VESA) approved the M1 Display Interface System for digital displays. The M1 system is a versatile and convenient system designed for computer displays,... more/see it nowspecifically digital projectors. M1 supports both analog and digital signals.
M1 is basically a modified DVI connector that can support DVI, VGA, USB and IEEE-1394 signals. The single connector replaces multiple connectors on projectors. An M1 cable can also be used to power accessories, such as interface cards for PDAs.
There are three primary types of M1 connectors:
–M1-DA (digital and analog). This is the most common connector, and it supports VGA, USB and DVI signals.
–M1-D (digital) supports DVI signals.
–M1-A (analog) supports VGA signals.
The M1 standard does not cover any signal specifications or detailed connector specifications. collapse
Black Box Explains... Spread Spectrum wireless technology.
Frequency-Hopping Spread Spectrum wireless communication provides error-free transmission, top security, and high levels of throughput without the need for an FCC site license. The key to Spread Spectrum is a... more/see it nowfrequency-hopping transceiver.
Narrow-band frequency hoppers use a predefined algorithm to maintain synchronization and high throughput between master and remote modems. They achieve this by continually switching or “hopping” from one transmission frequency to another throughout the Spread Spectrum band. The sequence of frequencies is very difficult to predict and thus nearly impossible to eavesdrop on or jam. If interference is encountered at any particular frequency, the built-in error correction detects it and resends the data packet at the next frequency hop. Because EMI/RFI interference rarely affects the entire available bandwidth, and each frequency hop is at least 6 MHz, the radio transmitter has access to as many as 100 frequencies within the spectrum to avoid interference and ensure that data gets through. collapse
Black Box Explains... Industrial modem benefits.
Not all modems shuttle data in air-conditioned, climate-controlled comfort. And modems that operate in cozy environments have absolutely no business being exposed to harsh industrial conditions or to the elements.
But... more/see it nowjust because you work in a rough-and-tumble place doesnt mean you have to sacrifice the convenience of a good modem. Instead, you should opt for an industrial modem. There are many industrial modems built for various degrees of extremity.
Survivability depends on reliability.
Sure, standard modems give you access to data in remote sites or enable you to service equipment on the plant floor—and you can do all this from the convenience of your office. However, these benefits are only possible if your modem can continue to function in its environment. And since standard modems arent built for adverse conditions, theyre not going to be reliable.
No penalties for interference.
Electrical control equipment—such as motors, relays, compressors, and generators—emit electromagnetic interference (EMI) that can affect the performance and reliability of a standard telephone modem.
EMI is emitted through power lines, the RS-232 communications cable, or through the telephone line itself. The very means of data communication, cable, is often the worst enemy of the standard modems that use it.
An industrial modem, on the other hand, has filters and superior EMI immunity to protect itself and your data. If you build your electrical cabinets to UL® or CSA standards, remember that your modem must also conform to UL® standard 508.
They go to extremes.
Temperature is the biggest killer of electronic equipment in industrial environments. The heat generated by industrial equipment in sealed enclosures or where space is a premium can make the temperature as much as 50 °F higher than the surrounding environment.
So standard modems cant take the heat. But what about being outdoors in the other extreme, cold weather? Well, standard modems cant take the cold either.
If you install your equipment in remote outdoor locations, it must work on the coldest days— especially those cold days when you least want to get in the car and go to the site to repair a standard modem that froze up.
Whether theyre placed in manufacturing environments or the great outdoors, industrial modems get the data through when you need it. They go to extremes for you.
Heavy metal for all kinds of banging around.
Industrial modems are built with durable metal enclosures that protect circuitry in rough conditions and ward off signal-disrupting EMI. Plus, they feature steel-bolt flanges to anchor them. In short, industrial modems can take the physical, heavy-duty punishment thrown their way.
So where exactly can you use an industrial modem?
• Heavy industry and manufacturing
• Oil and gas fields
• Storage sites
• Utility substations
• Agricultural projects
• Military facilities
• Research installations
• Water/wastewater systems
and another thing!
If dedicated copper lines cant be run through industrial environments, or if the fiber optic option is cost-prohibitive, there are also wireless industrial modems that make line-of-sight connections. If theres a way to get the data through, industrial modems will get the job done.
Industrial modems remain in service for a very long time. But if you ever need a replacement that is hardware or software compatible, be assured that Black Box continues to support its products year after year—so you don’t spend your time re-engineering systems if you have to make a replacement. collapse
Black Box Explains...Microphone positioning.
Proper microphone positioning is especially important to take advantage of noise canceling microphones, which reject background noise.
For optimum performance, position the microphone one finger width away from your lower lip.
Black Box Explains... SNMP.
SNMP (Simple Network Management Protocol) management is the standard for LAN management, particularly in mission-critical applications. The standard is controlled by the Internet Engineering Task Force (IETF). It was designed... more/see it nowto manage network configuration, performance, faults, accounting, and security.
An SNMP agent must be present at the device level (a router or a hub, for example), either built into the unit or as a proxy agent, and is accessed through a remote terminal. SNMP does not follow a polling protocol. It waits to receive data from the remote device or sends data based on operator commands.
By using one common set of standards, SNMP enables network administrators to manage, monitor, and control their SNMP-compliant network equipment with one management system and from one management station. If a network device goes down, it|s possible to both pinpoint and troubleshoot the problem more efficiently. And a network administrator isnt limited to equipment from just one vendor when using an SNMP program. 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