Beat the heat: efficient cooling in the data center

Cooling in the data center can be a lot like a black money hole, in that it’s a big energy sucker. How can you keep it cool and balance your budget by using efficient cooling technology? We know that the growing demand for power is a challenge, so choosing the best system for your data center is important.

Fortunately, there are a number of cooling methods to choose from, whether you are building a new data center or retrofitting one. And emerging green technologies offer exciting possibilities for advances in efficiency and cost savings.

Whether under the floor, above the floor, in the rack, or above the rack, the requirement of data center cooling remains the same: Warm air must be moved away from equipment and cool air towards it. Understanding the factors that can hinder or even prevent this from happening is one of the first steps to improving data center efficiency.

Air conditioners and air handlers
The familiar air conditioner (AC) unit, installed in the data center and connected to outside condensing units, uses a fan system to move cool and hot air where they need to be. It’s much like the systems used in residential settings except that, in building, cooling, the evaporator coil and blower are separate from the condenser coil, compressor, and condenser blower, while in electronics cooling they are packaged together in one unit.

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The relationship between switches, media converters, and OSI layers

Today’s media converters are often switches, and switches often act as media converters. Plus, both switches and media converters are frequently described in terms of layers—Layer 2, Layer 3. How can you tell what the heck you’re looking at?

Most of the confusion happens around OSI Layer 2 where Layer 1 media converters have evolved to meet basic switches. And today’s switches are rapidly advancing into Layer 3 and 4, territory formerly held by routers, muddying the waters still more.

A clear understanding of what OSI layers do, and what the differences between devices operating at different layers are, will help you select the right device.

OSI is a layered network design framework. The layers are referenced in the Open Systems Interconnection (OSI) Reference Model (which provides a layered network design framework that establishes a standard so that devices from different vendors work together). The OSI model is hierarchical. The layer at which a switch or a media converter operates determines which addressing detail it reads as data passes through.

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You’re invited!

Black Box Technology Center Open House

We would like to personally invite you to our Technology Center Open House!

What: Black Box Technology Center Open House
When: Wednesday, April 27th, 2011
7:30 a.m. – 7:00 p.m.
Refreshments will be served.
Where: Black Box Corporate Headquarters
1000 Park Drive Lawrence, PA 15055-1018

Click here for directions!

The Black Box Technology Center is a cutting-edge display for customer and partner demonstrations, as well as training, in a live, configurable environment. It brings to life complex technologies such as network security, desktop virtualization, digital signage, advanced switching, and the latest in cooling technologies. The Technology Center showcases more than 100 Black Box solutions.

For more information and to register, click here.

Beware of the Microchip: TEMPEST Standards and Common Criteria

It should come as no surprise that the federal government is concerned about signal leakage. In fact, its interest goes back to the days of World War II when the Army was trying to exploit weaknesses of enemy combat phones and radio transmitters. Since then, the scope of the government’s interest has broadened beyond the battlefield. In the last 40 years, the National Security Agency (NSA) has taken several industry measurement standards for signal protection and greatly enhanced them.

These enhanced criteria are commonly referred to as the TEMPEST standards (although the NSA also calls them EMSEC standards, short for “emissions security”). TEMPEST pertains to technical security countermeasures, standards, and instrumentation that prevent or minimize the exploitation of vulnerable data communications equipment by technical surveillance (A.K.A. eavesdropping!). It involves designing circuits to minimize emanations. Another set of testing standards is called Common Criteria (EAL4+). Both standards are important, but they test for different things.

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Certify fiber optic cable like a champ

If you’re accustomed to certifying copper cable, you’ll be pleasantly surprised at how easy it is to certify fiber optic cable because it’s immune to electrical interference. You only need to check a few measurements.

Attenuation (or decibel loss)—Measured in decibels/kilometer (dB/km), this is the decrease of signal strength as it travels through the fiber cable. Generally, attenuation problems are more common on multimode fiber optic cables.

Return loss—This is the amount of light reflected from the far end of the cable back to the source. The lower the number, the better. For example, a reading of -60 decibels is better than -20 decibels. Like attenuation, return loss is usually greater with multimode cable.

Graded refractive index—This measures how the light is sent down the fiber. This is commonly measured at wavelengths of 850 and 1300 nanometers. Compared to other operating frequencies, these two ranges yield the lowest intrinsic power loss (NOTE: This is valid for multimode fiber only.)

Propagation delay—This is the time it takes a signal to travel from one point to another over a transmission channel.

Optical time-domain reflectometry (OTDR)—This enables you to isolate cable faults by transmitting high-frequency pulses onto a cable and examining their reflections along the cable. With OTDR, you can also determine the length of a fiber optic cable because the OTDR value includes the distance the optic signal travels.

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