This Annex covers the application of a public ISDN providing Virtual Private Network (VPN) services to Private Integrated Services Network Exchanges (PINX).
This Annex contains only additional requirements to those in the main body of this Recommendation.
This Annex specifies additional protocol elements and call control procedures for the handling of calls in a VPN context at the T reference point of a public ISDN. The functionality provided by the public network may be:
– the emulation of an Originating PINX;
– the emulation of a Terminating PINX;
– the emulation of a Transit PINX;
– the emulation of a Relay Node;
– the emulation of an Incoming Gateway PINX;
– the emulation of an Outgoing Gateway PINX;
– the emulation of a combination of two or more of the above.
The support of these capabilities is a network option.
The public network can support the coexistence of multiple CNs in parallel, i.e. the resources of the public network are shared by multiple CNs. Each CN should be considered as a separate network.
The minimum requirement of the virtual Transit PINX and the virtual Gateway PINX is to be able to uniquely identify the CN to which a particular attached PINX belongs in order to ensure correct routeing of a particular call.
In addition, a physical PINX may support multiple CNs. Thus the mechanism for identifying a CN needs to be conveyed between a physical PINX and the public network.
This Annex does not cover the requirements for providing VPN services to terminals directly connected to the public network.
The specification included in this Annex does not imply any specific implementation technology or platform.