Apache CloudStack
An open source cloud computing and Infrastructure-as-a-Service (IaaS) platform developed to help make creating, deploying and managing cloud services easier by providing a complete “stack” of features and components for cloud environments.

API or Application Program Interface
An API is how one computer process (software) communicates with another. APIs may be standardized by industry agreement or government fiat, or proprietary to a specific application or vendor. The scope of the term API can vary based on its usage. It may refer to a single “call” by which one application can request information for another, the set of such calls for an application such as Google Maps, or the collection of all such application APIs used by an organization. In Cloud environments, this is sometimes referred to as “Web API.”

AWS or Amazon Web Services
Amazon’s suite of Public cloud services (includes EC2, RDS, S3, SQS and VPC) that together make up their cloud computing platform.

  • Amazon EC2 – Short for Amazon Elastic Computer Cloud, Amazon EC2 is a commercial Web service that lets customers “rent” computing resources from the EC2 public cloud. Amazon’s Elastic Compute Cloud Web service, which provides resizable computing capacity in the cloud so developers can enjoy great scalability for building applications.
  • Amazon S3 – Amazon Simple Storage Services — Amazon’s public cloud storage service.

Azure or Windows Azure
Microsoft’s public cloud computing platform.

Billing and service usage metering
You can be billed for resources as you use them. This pay-as-you-go model means usage is metered and you pay only for what you consume.

BPaaS or Business Process as a Service
A complete business process is provided as a service – such as billing, HR, payroll, advertising, etc.

Business Continuity
Business continuity is the activity performed by an organization to ensure that critical business functions will be available to customers, suppliers, regulators, and other entities that must have access to those functions. These activities include many daily chores such as project management, system backups, change control, and help desk. Business continuity is not something implemented at the time of a disaster; Business Continuity refers to those activities performed daily to maintain service, consistency, and recoverability.

BYOD or Bring Your Own Device
Some VoIP and Virtual Desktop providers allow a person to supply their own equipment. It refers to the policy of companies permitting employees to bring personally owned mobile devices (laptops, tablets, and smart phones) to their workplace, and use those devices to access privileged company information and applications.

CCMM or Cloud Computing Maturity Model
Defines five stages of evolution for an enterprise data center to migrate to cloud computing. The five stages are: consolidation, virtualization, automation, utility and cloud.

CDN or Content Delivery Network
A system consisting of multiple computers that contain copies of data, which are located in different places on the network so clients can access the copy closest to them.

Cloud App
Short for cloud application, cloud app is the phrase used to describe a software application that is never installed on a local computer. Instead, it is accessed via the Internet.

Cloud Application
A software application that is never installed on a local machine — it’s always accessed over the Internet. It is the top layer of the Cloud Computing Stack (aka Pyramid) where applications interact with client web browsers. Cloud Applications are tightly controlled, leaving little room for modification. Examples include: Gmail or

Cloud Application Management for Platforms or CAMP
CAMP, short for Cloud Application Management for Platforms, is a specification designed to ease management of applications — including packaging and deployment — across public and private cloud computing platforms.

Cloud Arcs
Short for cloud architectures, they are designs for software applications that can be accessed and used over the Internet.

Cloud as a service or CaaS
A cloud computing service that has been opened up into a platform that others can build upon.

Cloud Backup
Cloud backup, or cloud computer backup, refers to backing up data to a remote, cloud-based server. As a form of cloud storage, cloud backup data is stored in and accessible from multiple distributed and connected resources that comprise a cloud.

Cloud Backup Service Provider
A third-party entity that manages and distributes remote, cloud-based data backup services and solutions to customers from a central data center.

Cloud Backup Solutions
Cloud backup solutions enable enterprises or individuals to store their data and computer files in the cloud using a storage service provider, rather than storing the data locally on a physical disk, such as a hard drive or tape backup.

Cloud Bridge
Running an application in such a way that its components are integrated within multiple cloud environments (which could be any combination of internal/private and external/public clouds).

Cloud Broker
An entity that creates and maintains relationships with multiple cloud service providers. It acts as a liaison between cloud services customers and cloud service providers, selecting the best provider for each customer and monitoring the services.

Cloud bursting is a technique used by hybrid clouds to provide additional resources to private clouds on an as-needed basis. If the private cloud has the processing power to handle its workloads, the hybrid cloud is not used. It is what happens when your cloud has an outage or security breach and your data is unavailable. The term cloudburst is being used in two meanings, negative and positive:

  • Cloudburst (negative): The failure of a cloud computing environment due to the inability to handle a spike in demand.
  • Cloudburst (positive): The dynamic deployment of a software application that runs on internal organizational compute resources to a public cloud to address a spike in demand.

A datacenter in the “cloud” utilizing standards-based virtualized components as a datacenter-like infrastructure that rents its infrastructure.

Cloud client
Computing device for cloud computing. Updated version of thin client.

Cloud Computing
The term “cloud” refers to the way that networks, specifically the Internet, have been represented in engineering and network drawings for some time. In reality, the cloud is just the latest iteration of a concept that has been called many things in the past including ASP (application service provider), on-demand, utility computing and as a service (Software as a Service, Infrastructure as a Service).
Cloud technologies are simply a pool of computing resources (servers, storage, applications, and voice services) that is provided as-needed to businesses from a provider’s network, eliminating the need for on-site equipment, maintenance, and management. Cloud technologies enable IT departments to increase or add capabilities as needed without purchasing equipment and software, training employees to support it, and using office space, power, and cooling to house it. They provide end-users immediate access to new, always-on features from nearly any device in any location. They also provide the business a predictable, subscription-based, pay-per-use way to fund IT.

Cloud Computing Reseller
A company that purchases hosting services from a cloud server hosting or cloud computing provider and then re-sells them to its own customers.

Cloud Database
A database accessible to clients from the cloud and delivered to users on demand via the Internet from a cloud database provider’s servers. Also referred to as Database-as-a-Service (DBaaS), cloud databases can use cloud computing to achieve optimized scaling, high availability, multi-tenancy and effective resource allocation.

Cloud Elasticity or Cloud Scalability
The cloud is elastic, meaning that resource allocation can get bigger or smaller depending on demand. Elasticity enables scalability, which means that the cloud can scale upward for peak demand and downward for lighter demand. Scalability also means that an application can scale when adding users and when application requirements change.

Cloud Enablement
Cloud enablement is the process of creating, deploying and operating some or most of an organization’s IT infrastructure, software and resources through the cloud. Cloud enablement shifts in-house IT to a public, private or hybrid cloud environment. Cloud enablement service is delivered by cloud enablers or cloud service providers.

Cloud Enabler
A general term that refers to organizations (typically vendors) who are not cloud providers per se, but make available technology, such as cloudware, that enables cloud computing. Vendor that provides technology or service that enables a client or other vendor to take advantage of cloud computing.

Cloud Envy
Used to describe a vendor who jumps on the cloud computing bandwagon by rebranding existing services.

Cloud Governance and Compliance
Governance defines who’s responsible for what and the policies and procedures that your people or groups need to follow. Cloud governance requires governing your own infrastructure as well as infrastructure that you don’t totally control. Cloud governance has two key components: understanding compliance and risk and business performance goals. There are organizations, such as the Cloud Security Alliance, that promote the use of best practices for providing security assurance within Cloud Computing.

Cloud Hosting
A type of hosting where the client leases virtualized, dynamically scalable infrastructure on an as-needed basis. Users frequently have the choice of operating system and other infrastructure components. Typically cloud hosting is self-service, billed hourly or monthly, and controlled via a web interface or API.

Cloud Infrastructure
The “bottom” layer–or foundation–of the Cloud Pyramid is the delivery of computer infrastructure through paravirtualization. This includes servers, networks and other hardware appliances delivered as either Infrastructure Web Services or “cloudcenters”. Full control of the infrastructure is provided at this level.

Cloud Manageability
You need a consistent view across both on-premises and cloud-based environments. This includes managing the assets provisioning as well as the quality of service (QOS) you’re receiving from your service provider.

Cloud Management
Software and technologies designed for operating and monitoring the applications, data, and services residing in the cloud. Cloud management tools help ensure a company’s cloud computing-based resources are working optimally and properly interacting with users and other services.

Cloud Migration
The process of transitioning all or part of a company’s data, applications, and services from on-site premises behind the firewall to the cloud, where the information can be provided over the Internet on an on-demand basis.

Cloud OS
A phrase frequently used in place of Platform as a Service (PaaS) to denote an association to cloud computing.

Cloud Operating System or Cloud OS
A computer operating system that is specially designed to run in a provider’s datacenter and be delivered to the user over the Internet or another network also known as platform-as-a-service (PaaS). Windows Azure is an example of a cloud operating system or “cloud layer” that runs on Windows Server 2008. The term is also sometimes used to refer to cloud-based client operating systems such as Google’s Chrome OS.

Cloud-Oriented Architecture or COA
A term coined by Jeff Barr at Amazon Web Services to describe an architecture where applications act as services in the cloud and serve other applications in the cloud environment. An architecture for IT infrastructure and software applications that are optimized for use in cloud computing environments. The term is not yet in wide use, and as is the case for the term “cloud computing” itself, there is no common or generally accepted definition or specific description of a cloud-oriented architecture.

Cloud Platform
The “middle” layer of the Cloud Pyramid which provides a computing platform or framework (e.g., .NET, Ruby on Rails, or Python) as a service or stack. Control is limited to that of the platform or framework, but not at a lower level (server infrastructure). Examples include: Google AppEngine or Microsoft Azure.

Cloud Portability
In cloud (cloud computing) terminology, the phrase “cloud portability” means the ability to move applications and its associated data between one cloud provider and another — or between public and private cloud environments. See also Vendor lock-in.

Cloud provider
A company that provides cloud-based platform, infrastructure, application, or storage services to other organizations and/or individuals, usually for a fee.

Cloud Providers
Computing service providers whose product/platform is based on virtualization of computing resources and a utility-based payment model.

Cloud Pyramid
A visual representation of Cloud Computing layers where different segments are broken out by functionality. Simplified version includes: Infrastructure, Platform and Application layers.

Cloud Provider
A service provider who offers customers storage or software solutions available via a public or private network.

Cloud Provisioning
The deployment of a company’s cloud computing strategy, which typically first involves selecting which applications and services will reside in the cloud and which will remain on site behind the firewall or in a private cloud. Cloud provisioning also entails developing the processes for interfacing with the cloud’s applications and services as well as auditing and monitoring who accesses and utilizes the resources.

Cloud Security
The same security principles that apply to on-site computing apply to cloud computing security.

Cloud Servers
Virtualized servers running Windows or Linux operating systems that are instantiated via a web interface or API. Cloud Servers behave in the same manner as physical ones and can be controlled at an administrator or root level, depending on the server type and Cloud Hosting provider.

Cloud Server Hosting
Cloud server hosting is a type of hosting in which hosting services are made available to customers on demand via the Internet. Rather than being provided by a single server or virtual server, cloud server hosting services are provided by multiple connected servers that comprise a cloud.

Cloud Service Architecture or CSA
A term coined by Jeff Barr, chief evangelist at Amazon Web Services. The term describes an architecture in which applications and application components act as services on the cloud, which serve other applications within the same cloud environment.

Cloud Sourcing
Outsourcing storage or taking advantage of some other type of cloud service. The outsourcing of some IT operations to lower cost cloud services. Example: data backup

Cloud Standards
A standard is an agreed-upon approach for doing something. Cloud standards ensure interoperability, so you can take tools, applications, virtual images, and more, and use them in another cloud environment without having to do any rework. Portability lets you take one application or instance running on one vendor’s implementation and deploy it on another vendor’s implementation.

Cloud Storage
A service that allows customers to save data by transferring it over the Internet or another network to an offsite storage system maintained by a third party. Cloud storage means “the storage of data online in the cloud,” wherein a company’s data is stored in an accessible from multiple distributed and connected resources that comprise a cloud.

Cloud Storm or Cloudstorming
The act of connecting multiple cloud computing environments. Also referred to as cloud network.

Cloud Testing
Load and performance testing conducted on the applications and services provided via cloud computing — particularly the capability to access these services — in order to ensure optimal performance and scalability under a wide variety of conditions.

A general term referring to a variety of software, typically at the infrastructure level, that enables building, deploying, running or managing applications in a cloud computing environment. Ex. Evolve IP’s OSSmosis Enterprise Cloud Manager.

Slapping the word “cloud” on products and services you already have.

A group of linked computers that work together as if they were a single computer, for high availability and/or load balancing.

Consumption-based pricing model
A pricing model whereby the service provider charges its customers based on the amount of the service the customer consumes, rather than a time-based fee. For example, a cloud storage provider might charge per gigabyte of information stored. See also Subscription-based pricing model.

Customer self-service
A feature that allows customers to provision, manage, and terminate services themselves, without involving the service provider, via a Web interface or programmatic calls to service APIs.

Data in the cloud
Managing data in the cloud requires data security and privacy, including controls for moving data from point A to point B. It also includes managing data storage and the resources for large-scale data processing.

Disaster Recovery or DR
DR is the ability to restore access to records, data, hardware and software necessary to resume critical business operations after a disaster. There are facility disasters (e.g., fire in the building, bomb threats), local disasters (e.g., power outages, floods, earthquakes), and regional disasters (e.g., hurricanes [Hurricane Katrina was 500 miles wide], electrical grid failures). The cost to guarantee that you can resume operations usually increases as the distance and number of disaster recovery centers increases. This is often grouped with Business Continuity.

Disruptive technology
A term used in the business world to describe innovations that improve products or services in unexpected ways and change both the way things are done and the market. Cloud computing is often referred to as a disruptive technology because it has the potential to completely change the way IT services are procured, deployed, and maintained.

Elastic computing
The ability to dynamically provision and de-provision processing, memory, and storage resources to meet demands of peak usage without worrying about capacity planning and engineering for peak usage.

The process of transforming information (plaintext) in such a way as to make it unreadable (ciphertext) to anyone except those possessing a key to protect your information assets.

Enterprise Application
The term used to describe applications — or software — that a business would use to assist the organization in solving enterprise problems. When the word “enterprise” is combined with “application,” it usually refers to a software platform that is too large and too complex for individual or small business use.

Enterprise Cloud Backup
Enterprise-grade cloud backup solutions typically add essential features such as archiving and disaster recovery to cloud backup solutions.

External cloud
Public or private cloud services that are provided by a third party outside the organization. A cloud computing environment that is external to the boundaries of the organization.

Federation is the act of combining data or identities across multiple systems. Federation can be done by a cloud provider or by a cloud broker.

Funnel cloud
Discussion about cloud computing that goes round and round but never turns into action (never “touches the ground”)

Google Apps
Google’s SaaS offering that includes an office productivity suite, email, and document sharing, as well as Gmail, Google Talk for instant messaging, Google Calendar and Google Docs, spreadsheets, and presentations.

Hardware as a service; see IaaS.

Hosted application
An Internet-based or Web-based application software program that runs on a remote server and can be accessed via an Internet-connected PC or thin client. See also SaaS.

Hybrid cloud / Hybrid Cloud Storage
A combination of two or more clouds (private, community, or public) that remain unique entities but are bound together by standardized or proprietary technology that enables data and application portability. A networking environment that includes multiple integrated internal and/or external providers. Hybrid clouds combine aspects of both public and private clouds. A combination of public cloud storage and private cloud storage where some critical data resides in the enterprise’s private cloud while other data is stored and accessible from a public cloud storage provider.

Identity management
Managing personal identity information so that access to computer resources, applications, data, and services is controlled properly.

Infrastructure as a Service or IaaS
Cloud infrastructure services or “Infrastructure as a Service (IaaS)” delivers computer infrastructure, typically a platform virtualization environment, as a service. Rather than purchasing servers, software, data center space or network equipment, clients instead buy those resources as a fully outsourced service. The service is typically billed on a utility computing basis and amount of resources consumed (and therefore the cost) will typically reflect the level of activity. It is an evolution of web hosting and virtual private server offerings.

A global cloud of clouds, similar in concept to the Internet being a global network of networks. See also: Intracloud

An Intercloud consisting of only private clouds.

Internal Cloud
Another name for a private cloud. A type of private cloud whose services are provided by an IT department to those in its own organization.

An open source operating system based on Unix. It is the dominant operating system for cloud computing.

A Web-based application that combines data and/or functionality from multiple sources.

Microsoft Azure
Microsoft cloud services that provide the platform as a service (see PaaS), allowing developers to create cloud applications and services.

Software that sits between applications and operating systems, consisting of a set of services that enable interoperability in support of distributed architectures by passing data between applications. So, for example, the data in one database can be accessed through another database.

Mobile Cloud Storage
A form of cloud storage that applies to storing an individual’s mobile device data in the cloud and providing the individual with access to the data from anywhere.

In cloud computing, multi-tenant is the phrase used to describe multiple customers using the same public cloud.

Multitenancy is the property of multiple systems, applications or data from different enterprises hosted on the same physical hardware. Multitenancy is common to most cloud-based systems.

On-demand Service
A model by which a customer can purchase cloud services as needed; for instance, if customers need to utilize additional servers for the duration of a project, they can do so and then drop back to the previous level after the project is completed.

Online Backup
In storage technology, online backup means to back up data from your hard drive to a remote server or computer using a network connection. Online backup technology leverages the Internet and cloud computing to create an attractive off-site storage solution with little hardware requirements for any business of any size.

A cost model for cloud services that encompasses both subscription-based and consumption-based models, in contrast to traditional IT cost model that requires up-front capital expenditures for hardware and software.

Personal Cloud Storage
A form of cloud storage that applies to storing an individual’s data in the cloud and providing the individual with access to the data from anywhere. Personal cloud storage also often enables syncing and sharing stored data across multiple devices such as mobile phones and tablet computers. Personal cloud storage is also frequently referred to as mobile cloud storage or pocket cloud storage. Example: iCloud

Platform as a Service or PaaS
Cloud platform services, whereby the computing platform (operating system and associated services) is delivered as a service over the Internet by the provider. The PaaS layer offers black-box services with which developers can build applications on top of the compute infrastructure. This might include developer tools that are offered as a service to build services, or data access and database services, or billing services.

Private Cloud
Private Clouds provide a dedicated instance of these services for your exclusive use and, as a result, can be secured and accessed privately. While they are housed in provider’s data center, they do not leverage the pool of shared resources, so they cannot grow and shrink and do not include failover and redundancy. Private Clouds most times utilize the same technology (hardware, virtualization, security) as an on-premise deployment, but they are outsourced to a service provider for hosting and care and feeding of the environment. Visit ‘ What is private cloud ‘ for more information.

Private Cloud Project
Companies initiate private cloud projects to enable their IT infrastructure to become more capable of quickly adapting to continually evolving business needs and requirements. Private cloud projects can also be connected to public clouds to create hybrid clouds.

Private Cloud Security
A private cloud implementation aims to avoid many of the objections regarding cloud computing security. Because a private cloud setup is implemented safely within the corporate firewall, it remains under the control of the IT department.

Private Cloud Storage
A form of cloud storage where the enterprise data and cloud storage resources both reside within the enterprise’s data center and behind the firewall.

Public cloud
Public clouds provide a pool of shared computing resources, applications, and storage to the customer as a single virtualized service. They generally allow you to grow or shrink these resources as needed and often times provide built-in failover and redundancy. But, they are delivered (as the name suggests) publicly and in a defined fashion, so you are unable to secure your services with a private firewall or access them privately over your Wide Area Network (WAN). Public Clouds also generally require an on-staff development resource and in some cases a full re-factor of the application framework for proper functionality. The Public Cloud is generally referred to as a “revolutionary” approach to Cloud Computing as it brings many benefits but also a degree of complexity and know-how to fully leverage its capabilities.

Public Cloud Storage
A form of cloud storage where the enterprise and storage service provider are separate and the data is stored outside of the enterprise’s data center.

Rapid Elasticity
Elasticity is defined as the ability to scale resources both up and down as needed. To the consumer, the cloud appears to be infinite, and the consumer can purchase as much or as little computing power as they need. Defined by the National Institute of Standards and Technology (NIST) as one of the five essential characteristics of cloud computing.

Red Hat Cloud Computing
Red Hat Cloud Computing refers to solutions for private clouds, hybrid clouds, and public clouds offered by Red Hat.

Red Hat CloudForms
Red Hat CloudForms is an Infrastructure-as-a-Service (IaaS) offering that builds upon a collection of more than 60 open source projects. CloudForms include application lifecycle management capabilities as well as the capability to create hybrid public and private clouds from the broadest range of computing resources with unique portability across physical, virtual and cloud computing resources.

Red Hat OpenShift
OpenShift provides developers with a choice in languages, frameworks, and clouds to build, test, run, and manage Java, Ruby, PHP, Perl and Python applications. Developers can also choose the cloud provider the applications will run on.

Roaming workloads
The backend product of cloudcenters.

SaaS or Software as a Service
Cloud application services, whereby applications are delivered over the Internet by the provider, so that the applications don’t have to be purchased, installed, and run on the customer’s computers. SaaS providers were previously referred to as ASP (application service providers). In the SaaS layer, the service provider hosts the software so you don’t need to install it, manage it, or buy hardware for it. All you have to do is connect and use it. SaaS Examples include customer relationship management as a service.
An online SaaS company that is best known for delivering customer relationship management (CRM) software to companies over the Internet.

Self-service provisioning
Cloud customers can provision cloud services without going through a lengthy process. You request an amount of computing, storage, software, process, or more from the service provider. After you use these resources, they can be automatically deprovisioned.

Service migration
The act of moving from one cloud service or vendor to another.

Service provider
The company or organization that provides a public or private cloud service.

Service level agreement or SLA
A contractual agreement by which a service provider defines the level of service, responsibilities, priorities, and guarantees regarding availability, performance, and other aspects of the service.

Standardized interfaces
Cloud services should have standardized APIs, which provide instructions on how two application or data sources can communicate with each other. A standardized interface lets the customer more easily link cloud services together.

Storage Cloud
Storage cloud refers to the collection of multiple distributed and connected resources responsible for storing and managing data online in the cloud.

Subscription-based pricing model
A pricing model that lets customers pay a fee to use the service for a particular time period, often used for SaaS services. See also Consumption-based pricing model.

TCO or Total Cost of Ownership
TCO is an estimate of the total cost of a solution over time, usually a few years. It should include all costs, direct and indirect, associated with the solution. It helps determine the financial value of a change in operations. Because the cloud is a pay-as-you-go model, much of your financial future is predicted for you with a cloud-based solution. This means your method of comparing future costs has to reflect the factors the monthly cost of your cloud computing solution inherently provides, like RAM, Disk, licensing, support by qualified personnel, redundancy, scale for future needs, and disaster recovery to name a few. A lot of these factors are surprises that await you when buying, managing, and administering IT on your own with a premise-based solution.

Utility computing / Utility Pricing
Utility pricing is where the subscriber pays for resources as they are used instead of paying a fixed price independent of usage. In the current mode, a customer buys a server and pays for it as a capital expense, and then pays recurring maintenance fees. In a Cloud environment, online computing or storage is sold as a metered commercial service where the customer “rents” the resources and pays as they use, based on how much they use – similar to how a customer pays for electricity in their home.

Vendor lock-in
Dependency on the particular cloud vendor and difficulty moving from one cloud vendor to another due to lack of standardized protocols, APIs, data structures (schema), and service models.

Vertical cloud
A cloud computing environment that is optimized for use in a particular industry, such as health care or financial services.

Vertical Cloud Computing
A vertical cloud, or vertical cloud computing, is the phrase used to describe the optimization of cloud computing and cloud services for a particular vertical (e.g., a specific industry) or specific use application.

Virtual Data Center or Virtual Servers or vServer
A Virtual Data Center is a Virtual Private Cloud Computing Service that enables customers to leverage guaranteed resource reservation pools (processor, memory and disk resources) at a cloud service provider’s secure data center. A vServer is a virtual private cloud (VPC) server that leverages the scalability and failover of public cloud services with the privacy and security of dedicated hosting environments.

Virtual Desktop Infrastructure or VDI
A virtual desktop is an untethered virtual workspace that can be accessed from anywhere at any time on a variety of devices for a predictable monthly fee. By leveraging a Virtual Desktop Infrastructure (VDI), IT managers are freed from the need to “touch” each desktop for support or delivery of new applications, saving your staff time and keeping your employees productive. Because all of the employees’ “work” is being done in the cloud, you can extend the usable life of older computers, replace them with inexpensive thin clients, and even provide secure access from home PCs and iPads.

Virtual Private Cloud or VPC
The term describes a concept that is similar to, and derived from, the familiar concept of a Virtual Private Network (VPN), but applied to cloud computing. It is the notion of turning a public cloud into a virtual private cloud, particularly in terms of security and the ability to create a VPC across components that are both within the cloud and external to it. e.g., the Amazon VPC that allows Amazon EC2 to connect to legacy infrastructure on an IPsec VPN. A Virtual Private Cloud leverages the scalability and failover of public cloud services with the privacy and security of dedicated environments. Virtual Private Cloud functions perfectly with both new and legacy applications and provides predictable, stable, and secure architecture with the resiliency and on-demand expansion capabilities that most expect with the “cloud”. Often referred to as the “evolutionary” approach, Virtual Private Cloud does not require changes to the application framework or special coding for proper migration. The Virtual Private Cloud delivers the best of both worlds.

Virtual private data center
Resources grouped according to specific business objectives.

Virtual machine or VM
A file (typically called an image) that, when executed, looks to the user like an actual machine. Infrastructure as a Service is often provided as a VM image that can be started or stopped as needed. Changes made to the VM while it is running can be stored to disk to make them persistent.

VMware vCloud Connector
The VMware vCloud Connector is a tool that facilitates hybrid cloud computing for organizations. The vCloud Connector essentially helps to orchestrate and administer the migration of VMs across different data centers and clouds.


ACD or Automatic Call Distributor
A specialized phone system used for handling many incoming calls. The ACD will recognize and answer an incoming call; will look in its database for call routing instructions. It will send the call to a recording or IVR or will send the call to an available agent according to the instructions for that call. An ACD will normally produce management information tracking both calls and agent performance.

Auto Attendant
An automatic response system, such as a voice presenting options such as press 2 for sales, 5 for Lisa, etc., which handles incoming calls and sends them to the appropriate phone or message.

A high speed fiber network with a large capacity that connects major cities throughout the world.

Bandwidth is the volume of data that can be transmitted over a communication line in a fixed amount of time. It is expressed in bits per second (bps), 1000 bits per second (kbps), or bytes per second for digital devices and in cycles per second, or Hertz (Hz) for analog devices. Bandwidth can also be defined as the difference between a band of frequencies or wavelengths.

Call Center Agent
The person that handles calls in a contact center. Also referred to as a customer service representative (CSR).

Call Control
In telephony, call control refers to the software within a telephone switch that supplies its central function. Call control decodes addressing information and routes telephone calls from one endpoint to another. It also creates the features that can be used to adapt standard switch operation to the needs of users, such as “Call Waiting”, “Call Forward on Busy” etc.

Call Hunting or Hunt Group
A calling feature for inbound calls that will “roll past” a busy signal or try multiple numbers until the call is answered.

CDR or Call Detail Record
Details about a specific call that includes duration, origination, destination, and billable information, as well as other pertinent information.

The loss of speech-signal components, resulting in the dropping of the initial or end parts of a word or words.

Cloud Call Center
A Call Center solution that is hosted in a service provider’s cloud and is delivered in an economical monthly subscription model. It provides contact center managers with more control and deeper insight into their contact center operations than a premise-based system. By establishing a single cloud-based contact center across multiple locations, call centers can streamline operations and maximize staffing.

Cloud Communications
Cloud refers to the Internet. Cloud Communications uses the Internet as a way to have users connect to host equipment at a remote location which then connect to other users allowing phone calls. Synonymous with hosted VoIP or Internet Phone Service.

Codec is a term that arises from the Compressor-Decompressor or enCOder/DECoder process. It is used for software or hardware devices that can convert or transform a data stream. For instance, at the transmitting end codecs can encode a data stream or data signal for easy transmission, storage or encryption. At the receiving end, they can decode the signal in the appropriate form for viewing. They are most suitable for video conferencing and streaming media solutions.

CTI or Computer Telephony Integration
The linking of the computer in the ACD system to the computer which houses the company’s database to permit faster and more efficient handling of calls. Screen pop is a function of CTI which can direct the data screen of the calling person’s account to the terminal of the agent as the call is being routed there, saving the agent from having to identify the caller’s account number, key it in, and wait for computer response. Also permits transfer of data screens to a second agent when a call is transferred and many other capabilities impossible with only one or the other system independently.

DID or Direct Inward Dialing
A service that allows an enterprise to allocate individual phone numbers to each person within its PBX system.

DNIS or Dialed Number Identification Service
DNIS is a feature of 800 and 900 lines that provide the number the caller dialed to the receiving switch. Using DNIS capabilities, one trunk group can be used to serve multiple applications. Generally, a DNIS number will be used to identify to the answering telephone system the “application” the caller dialed.

A computer program running on a web server, translating domain names into IP addresses. In the last years, special types of domain names records were added to the DNS worldwide system, which provides support to SIP/VoIP (SRV/NAPTR, ENUM).

DSL or Digital Subscriber Line
Phone technology that allows a broadband internet digital connection to be carried over existing copper phone lines, while still allowing the phone service carry analog signals over the same line.

E911 is the short form of the term Enhanced 911, and is used for providing emergency service on cellular and Internet voice calls.

A feature that allows calls to find you wherever you are, ringing multiple phones (such as your cell phone, home phone, and work phone) all at once.

FMC or Fixed Mobile Convergence
FMC is the integrated connectivity between fixed and wireless telecommunications network. It is used by carriers to provide a seamless switching between cellular and local networks for mobile phone users.

Frame Relay
In data communications, a packet switching method that uses available bandwidth only when it is needed. This fast packet switching method is efficient enough to transmit voice communications to the proper network management

IM or Instant Messaging or Chat
Instant Messaging is a software that allows users to exchange messages in real time. However, to do so both the users must be logged on to the instant messaging service at the same time. Some of the popular IM services are: Microsoft Lync, MSN Messenger, and Yahoo! Messenger.

IP or Internet Protocol
IP defines the way data packets, also called datagrams, should be moved between the destination and the source. More technically, it can be defined as the network layer protocol in the TCP/IP communications protocol suite.

IP address
An IP address, also known as Internet Protocol address, is the machine number used to identify all devices that are connected to the net. Each device has its own unique number which it uses to communicate. This number is fixed in the case of those computing devices that have a fixed IP address. The rest are allotted a dynamic IP address, which is valid for the period they are connected to the net. The numbers range from to

IP mapping
IP mapping is the process of identifying IP addresses on the basis of their geographical locations. The mapping enables web administrators to pinpoint the location of any computing device connected to the Internet.

IP Phone or Internet Phone or SIP Phone or VoIP Phone
An IP phone is one that converts voice into digital packets and vice versa to make phone calls over Internet possible. It has built-in IP signaling protocols such as SIP or H.323 that ensure that the voice is routed to the right destination over the net. On the media side, the IP Phone uses audio or/and video codecs such as G.711 or/and H.261 respectively over RTP. The IP phones come with several values added services like voicemail, e-mail, call number blocking etc.

ISP or Internet Service Provider
A business that provides subscriber-based access to the Internet. Subscribers can be individuals or businesses. According to Jack Rickard, publisher of Boardwatch Magazine, ISPs operate at the fourth or lowest level of the Internet. At the third level, regional providers aggregate traffic from lower-order ISPs to the second, backbone level. The highest level in North America is the NAP (Network Access Point), which act as peer-to-peer interconnection points for the largest backbones. There are three “official” NAPs located in San Francisco, Chicago and Pennsauken, New Jersey. ISPs use both Internet Routers, Servers and Rack-Mounted modems to provide a variety of services including Web Site hosting, FTP service, e-mail accounts, unified messaging, audio and video broadcasting and in some cases – Internet Telephony and Fax Gateway service.

IVR or Interactive Voice Response
A software information system integrated into a phone system that speaks to callers and uses menus and voice responses. By using touch-tone keypad entries to interact with the software, you get voice responses with real time data. An IVR platform uses computer telephony components to translate callers’ touch-tones or voice commands into computer queries after the callers hear an audio menu. These queries are then “fetched” by the IVR platform from the host computer. In some cases, the information resides in the same platform (self-hosted).

As data load increases and decreases, routers on the Internet can create slightly different times that individual packets take to travel from one point to another point. This variation in time is known as jitter.

A group of computers and associated devices that share a common communications line or wireless link and typically share the resources of a single processor or server within a small geographic area (for example, within an office building).

The time it takes for a packet to reach its destination. Higher delay times can be an issue, especially for VoIP, where voice delay can be recognized with latency higher than 150 milliseconds. Higher than 500 milliseconds and the conversation is going to be very problematic.

MOS or Mean Opinion Score
The Mean Opinion Score (MOS) provides a numerical indication of the perceived quality of voice transmission after compression and/or transmission and is expressed as a number in the range 1 to 5, where 1 is lowest perceived audio quality and 5 is the highest perceived audio quality measurement.

Multiprotocol Label Switching or MPLS
A method for maximizing network speeds on high traffic networks. It enables enterprises and service providers to build intelligent networks that deliver scalable, end-to-end services

A logically grouped unit of data. Packets contain a payload (the information to be transmitted), originator, destination and synchronizing information. The idea with packets is to transmit them over a network so each individual packet can be sent along the most optimal route to its. Packets are assembled on one end of the communication and re-assembled on the receiving end based on the header addressing information at the front of each packet. Routers in the network will store and forward packets based on network delays, errors and re-transmittal requests from the receiving end.

Packet loss
Packet loss is the term used to indicate the loss of data packets during transmission over a computer network. This may happen on account of high network latency or on account of overloading of switches or routers that are unable to process or route all the incoming data. Packet loss sounds like an echo when speaking on a VoIP phone. Your hosted VoIP PBX should not allow for more than 1 or 2% of packet loss, and obviously the less the better.

Packet Switching
A means of economically sending and receiving data over alternate, multiple network channels. The premise for packet switching is the packet, a small bundle of information containing the payload and routing information. Packet switching takes data, breaks it down into packets, transmits the packets and does the reverse on the other end. Packets can be sent in order and then be received in a different order – only to be put back in the correct order in seconds. There are slow packet switching networks, like the old SNA networks – and there are fast packet networks based on Frame Relay and ATM. Although traditionally used for data, packet networks, especially well-managed ones, are becoming suitable for real-time transmission of voice and video.

PBX or Private Branch Exchange
A private telephone switching system that allows outside phone lines from a telecommunications provider to connect to extensions within the office or building. They usually have multiple features including call forwarding, rollover, paging and voice mail.

POE or Power over Ethernet
A system to transmit electrical power over a standard twisted pair Ethernet cable.

POP or Point of Presence
Point of Presence, the equivalent of a local phone company’s central office. The place your long distance carrier terminates your long distance lines just before those lines are connected to your local phone company’s lines, or to your own direct hookup.

POTS or Plain Old Telephone System
The familiar single phone line, single phone number system that has been in existence for many years.

In computer and telecommunications networks, presence information is a status indicator that conveys ability and willingness of a potential communication partner—for example, a user – to communicate. A user’s client provides presence information (presence state) via a network connection to a presence service, which is stored in what constitutes his personal availability record and can be made available for distribution to other users (called watchers) to convey his availability for communication. Presence information has wide application in many communication services and is one of the innovations driving the popularity of instant messaging or recent implementations of voice over IP clients.

PRI or Primary Rate Interface
The Primary Rate Interface consists of 23 B-channels and one 64 Kpbs D-channel using a T-1 line and can have up to 1.544 Mbps service. Typically, it is a dynamic circuit that delivers both voice and data, giving preference for voice. When a channel is not carrying voice it is automatically allocated for data.

PSTN or Public Switched Telephone Service
The combination of local, long-distance and international carriers that make up the worldwide telephone network.

QoS or Quality of Service
The ability of a network (including applications, hosts, and infrastructure devices) to deliver traffic with minimum delay and maximum availability.

A router is a device connected to at least two networks that determine the next network point to forward a packet to. The decision of which way to send each information packet is based on its current understanding of the networks that it is connected to.

RTP or Real-Time Transport Protocol
An Internet protocol that functions for end-to-end network connections for applications that use audio or video.

SIP or Session Initiation Protocol
A signaling protocol for Internet conferencing, telephony, and instant messaging. It is a request-response protocol, dealing with requests from clients and responses from servers. initiating an interactive user session.

SIP Trunking
The use of VoIP to facilitate the connection of typically a PBX to the Internet, where the Internet replaces the conventional telephone trunk, allowing a business to communicate with traditional PSTN telephone subscribers worldwide by connecting to an ITSP (Internet Telephony Service Provider). SIP trunking can save money and offer services to an IP-PBX.

Soft Phone
IP telephony software that allows end users to send and receive calls over the computer or handheld PC device (PDA) over the Internet. Typically used in conjunction with a headset and microphone there are many free softphones that are available.

Soft switch
It is a software application that is used to keep track of, monitor or regulate connections at the junction point between circuit and packet networks. This software is loaded in computers and is now replacing hardware switches on most telecom networks.

A switch is a device that keeps a record of the MAC addresses of all devices connected to it and then channels incoming data from any of multiple input ports to the specific output port that will take the data toward its intended destination.

North American digital standard for high-capacity transmission of telephony and data communications. In telephone, T-1 provides a 1.544 Mbps link which is broken down into 24 discrete, 64 Kpbs voice-grade channels. In data communications, T-1 links are used to directly connect CPE (Customer Premises Equipment) routers to the Internet and for Private Data Network or VPN circuits.

Unified Communications or UC
The integration of real-time communication services such as instant messaging (chat), presence information, telephony (including IP telephony), video conferencing, data sharing (including web connected electronic whiteboards aka IWB’s or Interactive White Boards), call control and speech recognition with non-real-time communication services such as unified messaging (integrated voicemail, e-mail, SMS and fax). UC is not necessarily a single product, but a set of products that provides a consistent unified user interface and user experience across multiple devices and media types.

Unified Messaging
Unified Messaging is the integration of different electronic messaging and communications media (e-mail, SMS, Fax, voicemail, video messaging, etc.) technologies into a single interface, accessible from a variety of different devices. While traditional communications systems delivered messages into several different types of stores such as voicemail systems, e-mail servers, and stand-alone fax machines, with Unified Messaging all types of messages are stored in one system. Voicemail messages, for example, can be delivered directly into the user’s inbox and played either through a headset or the computer’s speaker. This simplifies the user’s experience (only one place to check for messages) and can offer new options for workflow such as appending notes or documents to forwarded voicemails.

Virtual Call Center
The concept of having network and agent resources that are located at multiple physical sites perform as if all resources were located at a single site.

VoIP or Voice over IP or Voice over Internet Protocol
The transmission of voice over the Internet as digital packets rather than the traditional circuit-committed protocols of the PSTN. VoIP uses real-time protocol (RTP) to help ensure that the packets get delivered in a timely way. Visit ‘What is VoIP?’ for more information.

VoIP Gateway
A network device that converts voice and fax calls in real time from the public switched telephone network (PSTN) to an IP network.


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Patton’s VoIP Glossary’s Glossary for VoIP Associated Terms