The Windows Azure Platform is a Microsoft cloud platform used to build, host and scale web applications through Microsoft data centers. wikipedia.org

Windows Server is a brand name for a group of server operating systems released by Microsoft. wikipedia.org

Microsoft Exchange Server is the server side of a client_server, collaborative application product developed by Microsoft. It is part of the Microsoft Servers line of server products and is used by enterprises using Microsoft infrastructure products. wikipedia.org

FreePBX is a GUI (graphical user interface) that controls and manages Asterisk, an open source telephony engine software.

A firewall is a device or set of devices designed to permit or deny network transmissions based upon a set of rules and is frequently used to protect networks from unauthorized access while permitting legitimate communications to pass. wikipedia.org

Cisco Systems, Inc. is an American multinational corporation that designs, manufactures, and sells networking equipment. It has a full range of router products from small business to enterprise solutions, typically using its own Cisco IOS operating system. wikipedia.org

Active Directory (AD) is a directory service created by Microsoft for Windows domain networks. wikipedia.org

Microsoft Hyper-V is a hypervisor-based virtualization system for x86-64 systems. wikipedia.org

Voice over IP (VoIP, abbreviation of voice over Internet Protocol) commonly refers to the communication protocols, technologies, methodologies, and transmission techniques involved in the delivery of voice communications and multimedia sessions over Internet Protocol (IP) networks, such as the Internet. wikipedia.org

Cloud computing is a type of Internet-based computing that provides shared computer processing resources and data to computers and other devices on demand. wikipedia.org

A storage area network (SAN) is a network which provides access to consolidated, block level data storage. wikipedia.org