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There are several Wireless LAN Standards, including b, g, and n, which exist in the 2.4 GHz band. These standards need around 20 MHz of radio frequency in order to transmit their signals. In this video, Ben Miller discusses how to pick access points and channels for optimal performance.

Are you at a crossroads professionally or looking to start training for a new job? If so, you might want to consider pursuing network administration as a career. Network administrators are responsible for maintaining computer hardware and software systems that make up a computer network, including maintaining and monitoring active data networks, converged infrastructure networks, and related network equipment.

I recently responded to a message on LinkedIn from a regular reader of this blog. He asked several questions which I will answer over the course of several posts. As part of his first question, he described a strategy report that his group is producing. The audience for this strategy report considers ITIL important to the future of their business, and so he must describe which ITIL processes his data center operations group works most closely with.

The technologies examined reduce operational expenses (OpEx), not capital expenses (CapEx) that has traditionally been the focus of virtualization. Many companies implemented virtualization with the goal of saving money in the form of fewer servers to buy with a side benefit of reducing the footprint of the servers and lowering the required power and cooling. Most of the savings were in capital, but do not expect the same with many of the technologies listed here, because some may even require some additional capital expenditures, at least for software, in order to save on the day-to-day operations of IT. The bigger cost in running an IT department is in the OpEx category anyway, so savings there are recurring.

Answer? When it is flagged as a retransmission in Wireshark!

vSphere 5.5 is now available with myriad small improvements such as a faster Web Client, LACP, Autoscale and higher configuration maximums. In addition, there are changes coming such as VSAN, which may be ground-breaking in regard to VM storage of the future. Since the release of vSphere 5.5, they have not yet announced a change to the blueprint for the test. That being the case, I will say, for now, that the VCP-510 test should remain unchanged as well. My goal here is not to reeducate you on everything that you need to know for the test; instead, it is to point out the few changes that might apply in your company or organization.

CompTIA has raised the bar for Network+ candidates. The new certification exam has significant changes to the five "domains" or knowledge areas with new content related to security, cloud, data-center and operational concerns and troubleshooting. There is also a greater emphasis on wireless networking and VoIP. Use this white paper to help you gain an overview of what's new and what's different.

Good question! There are lots of networks, so I’m sorry to say that it depends. Let me explain. The smallest computer-based networks are usually PANs or Personal Area Networks. They can connect a wireless keyboard, mouse, or other devices to a computer. You may find them wirelessly linking a printer to your computer. You may have noticed these all include wireless connections. A PAN most often uses wireless technologies like infrared and Bluetooth, so it is really a WPAN (Wireless Personal Area Network).

“Twisted Pair” is another way to identify a network cabling solution that’s also called Unshielded Twisted Pair (UTP) and was invented by Alexander Graham Bell in 1881. Indoor business telephone applications use them in 25-pair bundles. In homes, they were down to four wires, but in networking we use them in 8-wire cables. By twisting the pairs at different rates (twists per foot), cable manufacturers can reduce the electromagnetic pulses coming from the cable while improving the cable’s ability to reject common electronic noise from the environment.

The most obvious difference is that hubs operate at Layer 1 of the OSI model while bridges and switches work with MAC addresses at Layer 2 of the OSI model. Hubs are really just multi-port repeaters. They ignore the content of an Ethernet frame and simply resend every frame they receive out every interface on the hub. The challenge is that the Ethernet frames will show up at every device attached to a hub instead of just the intended destination (a security gap), and inbound frames often collide with outbound frames (a performance issue).