Black Box Explains... ServSwitch Multi and audio cable.
Get more out of your ServSwitch Multi. Add audio cable, a set of speakers, and a microphone to each CPU. Audio cable turns your ServSwitch Multi into the ideal system... more/see it nowfor education, training, retail, medical, and multimedia office environments.
Audio cable isnt just for the ServSwitch Multi either. You can also use it with servers that give off audible alarms.
So even if you dont have audio equipment now—plan ahead. When youre ready to add audio equipment, just plug in our audio cable. collapse
Black Box Explains...Benefits of T1 and E1.
If you manage a heavy-traffic data network and you demand high bandwidth for high speeds, Black Box has what you need to send your data digitally over super-fast T1 or... more/see it nowE1 communication lines.
Both T1 and E1 are foundations of global voice communication.
Developed more than 30 years ago and commercially available since 1983, T1 and E1 go virtually anywhere phone lines go, but faster.
T1 sends data up to 1.544 Mbps. E1 supports speeds to 2.048 Mbps. No matter where you need to connect—North, South, or Central America, Europe, or the Pacific Rim—T1 and E1 can get your data there—fast!
Both services provide flexibility for a multitude of applications.
Whether you need to drive a private, point-to-point line or a high-speed circuit; provide corporate access to the Internet or inbound access to your own webserver; or support a voice/data/fax/video WAN that extends halfway around the world, T1 or E1 can make the connection.
Both offer cost-effective connections.
In recent years, competition among telco service providers has led to increasingly more affordable prices for T1 and E1 services. In fact, most companies seriously considering a shift to T1 or E1 find they can negotiate even better rates with just a little comparative cost analysis.
• Trunking of V.90 and ISDN remote connection to a central location.
• Accessing public Frame Relay networks for voice, fax, and data.
• Merging voice and data traffic. A single T1 or E1 line can give you several additional voice and data lines at no additional cost.
• Making LAN connections. If you’re linking LANs, a T1 or E1 line offers excellent performance.
• Sending bandwidth-intensive data such as CAD/CAM, MRI, CAT-scan images, and other graphics with large files. collapse
Black Box Explains...How MicroRACK Cards fit together.
Slide a function card into the front of the rack. Then slide a connector card in from the back. The rest is simple. Just press the cards together firmly inside... more/see it nowthe rack to seat the connectors.
Changing systems? Its easy to change to a different connector card. Just contact us, and well find the right connection for you.
Add a hot-swappable power supply (AC for normal operation, VDC for battery-powered sites), and youre up and running. collapse
Black Box Explains...Layer 2, 3, and 4 switches.
... more/see it now
E-Mail, Diagnostics, Word Processing, Database
Shells and Gateway Workstation Software
TR=Token Ring; A=ARCNET®; P=PhoneNET®
With the rapid development of computer networks over the last decade, high-end switching has become one of the most important functions on a network for moving data efficiently and quickly from one place to another.
Here’s how a switch works: As data passes through the switch, it examines addressing information attached to each data packet. From this information, the switch determines the packet’s destination on the network. It then creates a virtual link to the destination and sends the packet there.
The efficiency and speed of a switch depends on its algorithms, its switching fabric, and its processor. Its complexity is determined by the layer at which the switch operates in the OSI (Open Systems Interconnection) Reference Model (see above).
OSI is a layered network design framework that establishes a standard so that devices from different vendors work together. Network addresses are based on this OSI Model and are hierarchical. The more details that are included, the more specific the address becomes and the easier it is to find.
The Layer at which the switch operates is determined by how much addressing detail the switch reads as data passes through.
Switches can also be considered low end or high end. A low-end switch operates in Layer 2 of the OSI Model and can also operate in a combination of Layers 2 and 3. High-end switches operate in Layer 3, Layer 4, or a combination of the two.
Layer 2 Switches (The Data-Link Layer)
Layer 2 switches operate using physical network addresses. Physical addresses, also known as link-layer, hardware, or MAC-layer addresses, identify individual devices. Most hardware devices are permanently assigned this number during the manufacturing process.
Switches operating at Layer 2 are very fast because they’re just sorting physical addresses, but they usually aren’t very smart—that is, they don’t look at the data packet very closely to learn anything more about where it’s headed.
Layer 3 Switches (The Network Layer)
Layer 3 switches use network or IP addresses that identify locations on the network. They read network addresses more closely than Layer 2 switches—they identify network locations as well as the physical device. A location can be a LAN workstation, a location in a computer’s memory, or even a different packet of data traveling through a network.
Switches operating at Layer 3 are smarter than Layer 2 devices and incorporate routing functions to actively calculate the best way to send a packet to its destination. But although they’re smarter, they may not be as fast if their algorithms, fabric, and processor don’t support high speeds.
Layer 4 Switches (The Transport Layer)
Layer 4 of the OSI Model coordinates communications between systems. Layer 4 switches are capable of identifying which application protocols (HTTP, SNTP, FTP, and so forth) are included with each packet, and they use this information to hand off the packet to the appropriate higher-layer software. Layer 4 switches make packet-forwarding decisions based not only on the MAC address and IP address, but also on the application to which a packet belongs.
Because Layer 4 devices enable you to establish priorities for network traffic based on application, you can assign a high priority to packets belonging to vital in-house applications such as Peoplesoft, with different forwarding rules for low-priority packets such as generic HTTP-based Internet traffic.
Layer 4 switches also provide an effective wire-speed security shield for your network because any company- or industry-specific protocols can be confined to only authorized switched ports or users. This security feature is often reinforced with traffic filtering and forwarding features. collapse
Black Box Explains...Link loss.
Media converters solve the problem of connecting different media types in mixed-media networks. In order to comply with IEEE standards, they implement IEEE data-encoding rules and the Link Integrity Test.
For... more/see it nowa twisted-pair segment, a link is a signal sent by the converters when the cable is in use. If no Link Integrity Test signal is received, the connected device assumes that the link is lost.
With fiber cable, a connected device checks a line by monitoring the Link Integrity Test signal from the converter and the power of the light being received. If the light’s power drops below a certain threshold, the link is lost. In either case, link loss usually results from a broken cable, which is the cause of approximately 70% of all LAN problems.
Link loss is often indicated by an LED on a connected network device. You can also monitor a link with network-management software, such as SNMP, which sends a TRAP (alert) to the management workstation when the link is lost.
Media converters actually function as two separate Multistation Access Units (MAUs). For example, one monitor is a twisted-pair segment and one monitor is a fiber segment. If a fiber cable is broken and the link is lost, a network manager on the twisted-pair end wont know there’s a problem until users on the fiber side report it.
To solve this problem, Black Box® Modular Media Converters feature a unique Link-Loss capability. This enables the link status on one segment to reflect the link status of the other segment. So if the link is lost on the fiber side, the link is disabled on the UTP segment as well. And the converters will send an SNMP TRAP indicating the loss of link to the management workstation. collapse
Black Box Explains... Multiplatform cabling environments.
When using a ServSwitch™ with multiple computer platforms, choosing which peripherals to use to control your diverse group of CPUs can be confusing. Because of the wide variation in connector... more/see it nowtypes and compatibilities, there is a hierarchy to follow when choosing your user station keyboard, monitor, and mouse.
1. If you have at least one Sun® computer in your application, you should use a Sun keyboard and mouse to control your CPUs.
2. If you have a mixture of PCs and Mac® computers, use your PC-style keyboard and mouse to control your CPUs. collapse
Black Box Explains...Choosing the right headset.
Black Box offers several headsets for office use. Choosing the right one for your application depends on your needs.
First, do you need a monaural, binaural, or stereo headset? Monaural headsets... more/see it nowhave only one earpiece, making it easy to have over-the-phone conversations as well as face-to-face interactions, such as in a busy call center setting (see models HS402 or 64338-31, for example). Binaural headsets have two earpieces, which are on the same audio channel (HS113A or 2009-820-105). They are great when a user needs to have long, over-the-phone conversations. Stereo headpieces also have two earpieces, but operate on distinct audio channels. These last types of earpieces are best for listening to music.
Secondly, comfort is a big factor, especially if you have to wear a headset all day. Do you want an over-the-head model? Or would you prefer to wear your headset behind the ear? Headsets with two earpieces are almost always over-the-head models (see H16N). For long-wear applications and optimum sound quality, these are a good choice. Over-the-ear models are better for in-office interactions, or for when you are on and off the phone all day (26089-11 or M140). The sound quality is still excellent, but they enable you to also be aware of your environment.
Thirdly, choose an amplifier that matches your telephone and the way you work. The Two-Prong Carbon Amplifier (HS101A) is designed for phones that have a two-prong headset port. Several headsets have amplifiers built-in, such as the Elite Call Center Headset (HS111A).
Most Black Box headsets are noise-canceling models that reduce background sounds. They are ideal for busy office environments.
We have wireless headset models, plus cords, plugs, and adapters that enable extra mobility during calls. In addition, we carry extra parts such as earhooks, ear pads, headbands, and microphone covers. collapse
Black Box Explains...Selecting fiber line drivers.
When choosing a fiber driver, you should make a power budget, calculate the speed and distance of your cable run, and know the interface requirements of all your devices.
Many of... more/see it nowour fiber drivers are for single-mode fiber optic cable. Compared to multimode fiber, single-mode delivers up to 50 times more distance. And single-mode at full-duplex enables up to two times the data throughput of multimode fiber. collapse
Black Box Explains...LAN switches.
Rush hour-all day, every day.
Applications such as document imaging, video/multimedia production, and intranetworking are very demanding. They generate huge data files that often must be transferred... more/see it nowbetween stations based on strict timing requirements. If such traffic is not transmitted efficiently, you end up with jerky video, on-screen graphics that take forever to load, or other irritating, debilitating problems.
These problems arise because in traditional LANs, only one network node transmits data at a time while all other stations listen. This works in conventional, server-based LANs where multiple workstations share files or applications housed on a central server. But if a network has several servers, or if it supports high-bandwidth, peer-to-peer applications such as videoconferencing, the one-station-at-a-time model just doesn’t work.
Ideally, each LAN workstation should be configured with its own dedicated LAN cable segment. But that’s neither practical nor affordable. A far more reasonable solution is a network designed to provide clear paths from each workstation to its destination on demand, whether that destination is another workstation or server.
These vehicles clear the lanes.
Unlike bridges and routers, which process data packets on an individual, first-come, first-served basis, switches maintain multiple, simultaneous data conversions among attached LAN segments.
From the perspective of an end-user workstation, a switched circuit appears to be a dedicated connection-a direct, full-speed LAN link to an attached server or other remote LAN node. Although this technique is somewhat different from what a LAN bridge or router does, switching hubs are based on similar technologies.
Which route will you choose?
Switching hubs that use bridging technologies are called Layer 2 switches-a reference to Layer 2 or the Data-Link Layer of the OSI Model. These switches operate using the MAC addresses in Layer 2 and are transparent to network protocols. Switches that use routing technologies are known as Layer 3 switches, referring to Layer 3—the Network Layer—of the OSI Model. These switches, like routers, represent the next higher level of intelligence in the hardware hierarchy. Rather than passing packets based on MAC addresses, these switches look into the data structure and route it based on the network addresses found in Layer 3. They are also dependent on the network protocol.
Layer 2 switches connect different parts of the same network as determined by the network number contained with the data packet. Layer 3 switches connect LANs or LAN segments with different network numbers.
If you’re subdividing an existing LAN, obviously you’re dealing with only one network and one network number, so you can install a Layer 2 switch wherever it will segment network traffic the best, and you don’t have to reconfigure the LAN. However, if you use a Layer 3 switch, you’ll have to reconfigure the segments to ensure that each has a different network number.
Similarly, if you’re connecting existing networks, you have to examine the currently configured network numbers before adding a switch. If the network numbers are the same, you need to use a Layer 2 switch. If they’re different, you must use a Layer 3 switch.
When dealing with multiple existing networks, you’ll find they usually use different network numbers. In this case, it’s preferable to use a Layer 3 switch (or possibly even a full-featured router) to avoid reconfiguring the network.
But what if you’re designing a network from scratch and can choose either type of switch? Your decision should be based on the expected complexity of your LAN. Layer 3 routing technology is well suited for complex networks. Layer 2 switches are recommended for smaller, less complex networks. collapse
Black Box Explains...Cabinet accessories.
Once you’ve chosen your cabinet, whether it be a customized Elite or an energy-saving ClimateCab, it’s time to
add accessories for even more function.
Cabinets have two sets of rails,... more/see it nowfront and back, where you can mount shelves, trays, cable managers, and power strips.
Shelves are an easy solution for storing things that aren’t rackmountable. The shelves attach to the rails; servers or other equipment sits on the shelves. Make sure the shelf has the weight capacity you need—some can hold hundreds of pounds. For easy access to components in your cabinet, choose a sliding shelf. There are also vented shelves that improve air circulation within the cabinet.
Although most shelves fit 19" rails, there are shelves that go on the less-common 23" rails. There are also brackets that can adapt many devices intended for 19" mounting to 23" rails.
Keyboard trays are space-saving solutions that also keep your data center organized. They slide neatly into your cabinet or rack—and out of your way—when not in use. And they usually fit into only 1U of rack space.
Further reduce clutter in your server room by using KVM trays that are 1- or 2U high mounted in your cabinet. Special features of Black Box® KVM trays include rock-solid construction, LEDs on the front panel for easy location in a darkened data center, and integrated KVM switching.
Front-panel controls enable you to use the buttons on a monitor bezel without pulling out the keyboard. Some trays have USB ports for access.
Cabinets usually have built-in troughs for cable routing, knockouts for cable pass-throughs, and tie-off points for cable management. You can also add horizontal or vertical cable managers to the cabinet’s rails to manage and route cables more efficiently. Cable managers control bend radius to protect cables from hidden crushes, kinks, and snags, and reduce maintenance time by keeping your cabinet neat and organized. Plus, properly managed cables help to improve airflow.
If you’ve got no room to spare in your cabinet, think SpaceGAIN. You might not think of a patch panel as an “accessory,” but SpaceGAIN angled-port and angled patch panels are not your average panels. They free up valuable space and eliminate the need for horizontal cable managers. You save time and money by routing cables directly into ports. And SpaceGAIN high-density feed-through patch panels enable you to fit 48 ports into only 1U of rack space, with no punchdowns needed.
To save even more space, use SpaceGAIN 90° Right-Angle CAT5e/CAT6 cables. Their up, down, left, or right angles save up to 4" of space in crowded cabinets.
PDUs and UPSs
Control the distribution of power in your cabinet with a power distribution unit (PDU). A PDU can be basic or “intelligent,” with surge protection, remote management, or power and environmental monitoring. Integrate a PDU directly into an uninterruptible power supply (UPS) for extra reliability.
Fans and blowers
Ventilation in your cabinets is critical for keeping vital equipment cool.
An enclosure blower draws cool air from a raised floor at the bottom of the cabinet and delivers it right across
the front of servers or other network components. It fits on standard 19" rails and uses only 2U of mounting space. This high level of ventilation lowers the temperature of cabinet hot spots by up to 15° F. Lowering temperatures protects your electronics against failure caused by overheating, which may enable you to install more equipment.
Fan panels or fan trays direct maximum airflow with very little noise to heat-sensitive rackmounted equipment. Position them in your cabinet wherever you need them the most.
Most network devices take in air through their front panels and expel it out the back. Filler panels in unused rack spaces help keep cool air in the front of the cabinet where it can be used by the equipment.
Most cabinets come with a lock and key, but more advanced options are available to provide a higher level of security. Keyless options include combination locks and biometric locks that read fingerprints. collapse