A virtual node (vnode) (also known as a Server Connection Definition) is a name defined on the local instance to identify a particular remote instance. Assigning a vnode name is typically the first step in the process of establishing connection and authorization data for a remote instance.

Whenever local users connect to a database on a remote instance or run an application that accesses a database on a remote instance, they must do one of the following:

Using vnodes is generally simpler for users because they only have to enter a single, user-friendly vnode name when they run an application, rather than detailed network-specific connection information. Another advantage of vnodes is that network changes can be updated for a vnode without notifying the user or changing the application.