Remote server applications

Remote access is the ability to access a network, a personal computer, a server, or other device from a distance for the purpose of controlling it or to access data. Today, remote access is usually accomplished over the Internet, although a local IP network, telephone lines, cellular service, or leased lines may also be used.

Remote access is a very general term that covers a wide range of applications from telecommuting to resetting a distant server. Here are just a few of the applications that fall under the remote access umbrella:

Remote network access
A common use for remote access is to provide corporate network access to employees who work at home or are in sales or other traveling positions. This kind of remote access typically uses IPsec VPN tunnels to authenticate and secure connections.

Remote desktop access
Remote desktop access enables users to access a computer remotely from another computer and take control of it as if it were local. This kind of remote control requires that special software—which is included with most operating systems—be installed and enabled. It’s often used by those who travel frequently to access their “home” computer, and by network administrators for remote server access. This remote access method has some inherent security concerns and is usually incompatible with firewalls, so it’s important to be aware of its limitations and use adequate security precautions.

Remote KVM access
A common application in organizations that maintain servers across multiple sites is server administration through an IP-enabled KVM switch. These IP-addressable switches support one or more servers and have an integral Web server, enabling users to access them over the Internet through a Web browser. Because they’re intended for Internet use, these switches offer authentication and encryption for secure connections.

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6 Things to consider before investing in VoIP

Voice over Internet Protocol, or VoIP, is a great cost-saving alternative to traditional telephone service that enables voice data to be transported over IP networks, like the Internet, instead of the public switched telephone network (PSTN) or a cellular network.

Because VoIP is inexpensive, has a worldwide reach, and operates on a few simple principles, it’s exploded in popularity in recent years—especially among both small and large businesses that incur significant long-distance telephone expenses. However, it’s not all fun and free calls. Below are six things to consider when you’re deciding whether or not to invest in VoIP.

1. Regulation vagaries
Much of the government regulation of VoIP is still being worked out. The U.S. government hasn’t decided whether VoIP is going to be regulated as phone service or whether to tax it. VoIP isn’t available worldwide because some governments fear the loss of tax revenue or control.

2. Compatibility
Although older VoIP equipment may still have some compatibility issues, current VoIP products from different vendors generally work together.

3. Cost
For all the popular talk about VoIP being free, it isn’t truly free. Any VoIP system has costs associated with its implementation—equipment, high-speed Internet access, and gateway service. So, although it’s inexpensive, it’s a long way from being free. For organizations with a high volume of long-distance calls, especially to international locations, VoIP almost always pays for itself quickly. However, private users or organizations with a low volume of long-distance calls primarily within the U.S., may find that a standard service is actually more economical in the short- to mid-term.

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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 harsh 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.

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NEMA ratings for enclosures

The National Electrical Manufacturers’ Association (NEMA) issues guidelines and ratings for an enclosure’s level of protection against contaminants that might come in contact with its enclosed equipment.

There are many numerical NEMA designations; we’ll discuss NEMA enclosures relevant to our on-line catalog: NEMA 3, NEMA 3R, NEMA 4, NEMA 4X, and NEMA 12.

NEMA 3 enclosures, designed for both indoor and outdoor use, provide protection against falling dirt, windblown dust, rain, sleet, and snow, as well as ice formation.

The NEMA 3R rating is identical to NEMA 3 except that it doesn’t specify protection against windblown dust.

NEMA 12 Wallmount Cabinet

ClimateCab NEMA 12 Wallmount Cabinet with Fan

NEMA 4 and 4X enclosures, also designed for indoor and outdoor use, protect against windblown dust and rain, splashing and hose-directed water, and ice formation. NEMA 4X goes further than NEMA 4, specifying that the enclosure will also protect against corrosion caused by the elements.

NEMA 12 enclosures are constructed for indoor use only and are designed to provide protection against falling dirt, circulating dust, lint, fibers, and dripping or splashing noncorrosive liquids. Protection against oil and coolant seepage is also a prerequisite for NEMA 12 designation.

Additional resources:
How NEMA standards are developed
How to read a NEMA standard