Autonomous System is a collection of routing nodes within the same administrative boundary (see BGP).

Border Gateway Protocol is a dynamic routing protocol used within the public Internet and private wide area networks. It can be used with a single autonomous system as an internal protocol (iBGP) and externally between autonomous systems (eBGP).

Customer Edge (router) is a term used to describe the role of a service provider router that sits on the perimeter of the provider network and connects to the local network on a customer’s premises.

Cloud Service Provider is the term used for a service provider capability that offers some or all of the key attributes necessary to be recognized as providing a cloud service. See The NIST Definition of Cloud Computing link in Section 7, References for more information.

Dynamic Host Configuration Protocol (rfc2131 and updates) is a protocol that enables a host to initialize on an IP address based network without a configured IP address. The protocol sets out a process for the host to assume a temporary address and request an IP address from a local or remote authority on the network to which it is connected.

Equal Cost Multi-Path is a routing term in which multiple next-hop choices all carry the same preference or “cost”, allowing traffic to be distributed across several links or devices to increase network resilience and performance.

VMware NSX Edge™ services gateway, sometimes simply “Edge”, or within vCloud Director “Edge Gateway” is a network and security virtual appliance that provides a number of services. See Section 2.2.2, Basic Cloud Service Provider Customer Topology for more information.

Multi-Protocol Label Switching is a network packet forwarding technology often used by service providers in their high-speed core networks. It uses hop-by-hop labels instead of destination addressing to enable traffic engineering, or management, of network paths and traffic flows.

Managed Services Provider is the term used for a service provider capability that does not typically provide a customer facing, self-service portal which customer use to directly control their environments.

Network Address Translation is a technique in which the source and/or destination addresses within an IP packet’s header are changed to hide the real address of a service. This is used for instance when devices on a private network connect to the public internet.

Network Interface Card (NIC) is the network adaptor which connects the ESX hosts to the external network infrastructure.

Operating system is the layer of software deployed onto the hardware layer of a physical or virtual computer. In VMware ESXi™ based solutions, the physical hardware uses VMware ESXi as its operating system and the virtual machines which ESXi supports run a variant of Microsoft Windows of a Linux distribution as the “guest OS”.

Provider Edge (router) is the term used to describe the role of a service provider router that connects multiple Customer Edge (CE) routers to the Provider’s core (or “P”) routers. In some provider platforms, the role of the CE router is virtualized, so the PE router is physically connected directly to the infrastructure supporting the customer solutions rather than through a physical per-tenant CE router.

Software-defined networking is a technology that creates end-user network elements, defined in software which are then deployed on top of a physical “underlay” network.

vCloud Director Network Isolation is a proprietary “MAC in MAC” encapsulation used in earlier versions of vCloud Director which allowed multiple, isolated customer networks to be “tunneled” between hosts over a single network.

Virtual data center is a collection of resources that are managed by vCloud Director. See Table 1 for more information.

Virtual IP is a term for an additional IP address that provides access to one or more devices without being assigned permanently to any of them. It is found in solutions where two or more devices provide high availability by presenting a single IP address for clients to connect to, without needing to know which device will service their request.

Virtual LAN is a network protocol which allows multiple, separate Layer 2 networks to be carried on the same physical (Layer 1) medium.

Virtual private network is a technique for separating traffic within a shared infrastructure. It is often used when an encrypted overlay is added to an insecure shared network such as the Internet, or when customer separation is provided over a service provider WAN.

Virtual routing and forwarding is a technique in which a single network device can manage multiple independent routing tables at once and apply the resulting forwarding rules to traffic associated with a specific instance.

Virtual eXtensible LAN is an encapsulation protocol that allows multiple, separate Layer 2 networks to be carried over a common Layer 3 network.

A wide area network is a telecommunications network that typically spans a large geographical area.