ITU-T X.305 PDF

Scope and field of application

This Recommendation defines those functionalities of subnetworks which relate to the OSI connection-mode network service in terms of:

a) the actions and events which occur at the interfaces to a subnetwork;

b) the parameters associated with each action and event, and the form which they take;

c) the interrelationship between, and the valid sequences of, these actions and events, for a given connection;

d) the interrelationship between different connections established through the same subnetwork.

This Recommendation also defines the ways different types of subnetworks support the OSI connectionmode network service, by including within the subnetwork part or all of the functionalities of subnetworks which relate to the OSI connection-mode network service.

The principal objective of this Recommendation is to provide guidance for consideration of interworking between subnetworks, in relation with the support of the OSI connection-mode network service.

This Recommendation does not specify products, or implementations of those functionalities in real network equipment, nor does it constrain the distribution of those functionalities among the pieces of network equipment considered within a given subnetwork (e.g. PDNs, IWFs, ISDNs,