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Subnetting is a complicated topic that has confused students for a very long time. However, subnetting is an important topic for many different certifications with various vendors, including Cisco. In the real world environment, people are used to just punching in the numbers in many of the free subnet calculators that are readily available on the internet. For exam purposes, you still have to do this in a very fast manner since many exams are time-based and you don't have the luxury of spending those precious minutes on any single question. This Cisco training whitepaper will solve some of those age-old and complicated subnetting puzzles.

Examine fifteen common myths surrounding virtualization, including many that prevent IT administrators (or their bosses) from getting the maximum value from virtualization. This paper is designed to be vendor-neutral; in other words, the basic concepts and advantages are the same whether you choose to use Citrix XenServer, VMware vSphere, Microsoft Hyper-V, or one of the many Linux-based solutions. We'll break the reasons into three broad categories (Cost/ROI, Performance, and Other), allowing you to focus in on a specific area if desired, or you can review the entire white paper for a broader view.

If you are upgrading to ESXi 5.1, there are some important facts that you should consider first. Upgrading involves many stages and processes that must be performed in a specific order. Many of these processes are one-way and do not provide a "back button." If you do not use care and consideration in your upgrade plan, you could possibly lose important data and configuration; and potentially even lose contact with your servers.

In 1998, the Internet Engineering Task Force (IETF) released RFC 2460, outlining the technical specifications of IPv6, which addressed the shortcomings of the aging IPv4 protocol. As with any evolution of technology, new elements exist in the protocol that may seem strange and unfamiliar. This certainly includes address representation, space, and so forth, but also includes a number of different types of addresses as well. A subset of these new addressing types has corresponding types in IPv4, but many will seem significantly different. The purpose of this white paper is to examine addressing classifications in detail and outline their functions within the context of the protocol.

As with the adoption of any new technology, the move from IP version 4 to IP version 6 will take a number of years to complete. During that transition phase, various mechanisms will be necessary to continue support of the older protocol as the newer gains widespread momentum. In addition, there has been some evolution even within the availability of these mechanisms, some of which have already passed from general use into deprecated status. Network engineering professionals already proficient in the use of IPv6, as well as the available coexistence mechanisms, will undoubtedly stay in high demand throughout this process.

This vSphere Essentials white paper will give you a basic understanding of some of the concerns or planning points to consider as you get ready to deploy vSphere in your organization. This is a glimpse into some of the essential things to consider for implementing vSphere. This will focus on some of the basics that vSphere administrators run into when installing the latest features and not realizing they still have some older versions implemented.

This white paper has three main goals. The first is to generate a better understanding of the cloud in both the business and IT communities. The second is to describe the major components of vCloud and the virtual datacenters they provide. The third is help businesses visualize and understand how vClouds could be beneficial in addressing their specific IT needs.

The OSI model is a conceptual tool used to discuss and describe network functions. The use of a standard reference model is essential to communicate ideas as well as create new technologies. It is a good idea to be familiar with the OSI model, the features assigned to each layer, and examples of common protocols or technologies associated with the OSI layers.

The utility that many senior VMware administrators rely on to address performance and troubleshooting issues is the built-in utility called ESXTOP. The tool has been built in to the hypervisor, and can be used in both ESXi and the old ESX host. The first tool many VMware Administrators rely upon is esxtop, to check real-time performance on an ESXi host using a command-line tool such as ssh to start the esxtop CLI utility. This paper will introduce and demonstrate how to start and use esxtop, specifically looking at the CPU fields. In addition, we will cover information that can be used to help with performance issues of the CPU. The esxtop utility is an excellent tool to use when you want to observe an individual ESXi host's performance.

One of the most important steps in mastering a new technology is learning the associated terminology or vocabulary. In the IT field, this can be a very challenging step, as much of the terminology is often used inconsistently. This white paper defines the terminology associated with IT virtualization. It is mainly vendor-agnostic, but it does provide some vendor-specific terms, product names, and feature names used by VMware, Citrix, and Microsoft.