(Continuation of Questions 2, 8 and 25/13 studied during 1997-2000)

Background and justification

As IP networks and IP-based applications gain importance in the industry there is an explosion of new architectures that model various functional and physical components of the IP/telephony networks. In particular, there has been steady introduction of new devices as well as continuing functional decomposition of the existing devices (such as an IP telephony gateway). Such functions and devices are introduced in support of new network capabilities and new services in both, the GSTN/PSTN and IP.

The architectural integration of IP networks and GSTN results in permanent changes to the very architectural principles of both types of network. The trend in the GSTN, for example, is to move intelligence toward the edges of the network (as in the cases where Internet service control is combined with the GSTN bearer service). Conversely, the dual trend in IP networks is to add intelligence into the network (e.g., policy and authentication servers). In addition, the traditionally connectionless network layer services of the IP networks are evolving into circuit-oriented services (as in the cases of label switching and resource reservation state maintenance).

These industry standards steadily introduce new architectural elements. In order to establish a common architecture for the industry for the convergence of telecommunications, information/computing and entertainment, substantial studies and frameworks are required to address issues in order to:

a) ensure interoperability of networks and applications;

b) facilitate innovation in use and application of the industry capabilities;

c) facilitate best utilization of the existing telecommunications infrastructure.

Recommendations are required which reflect the principles, requirements, frameworks and architectures for an overall heterogeneous network environment necessary to achieve interoperability in a multi-vendor, multi-network-operator situation.

Items for study

1) What new and amended framework Recommendations are required to ensure that the telecommunications infrastructure plays a full and vital role in the development of, and support for new and innovative services for global, new and existing markets?

2) Study of definitions, interrelation, and means of interconnection of architectural elements, protocol actions, pieces of equipment, etc. that have been identified in the IETF standards-track Requests for Comments (RFCs), ITU-T Recommendations, ISO standards, and normative output of other organizations recognized by ITU-T.

3) Development of the architectural principles of heterogeneous networks.

• Specify the architecture and the resulting relationship between layer services
• Specify network capabilities required to support IP based services including multigrade quality of services
• Extend relevant reference configurations to include multi-point connection aspects
• Consideration of interworking functions taking account of management, control and user planes for full featured integrated networks including mobile and interactive TV aspects.

4) Possible elimination of duplicated architectural elements (with subsequent communications to concerned standards organizations and forums).

5) Development of an unambiguous architecture for a global heterogeneous network environment including mobile and interactive TV (e.g. DVB) aspects.

The resulting architectural principles and the architecture itself should be published as ITU-T Recommendations, which should be re-issued on an on-going basis as the global heterogeneous network environment grows.

Specific tasks and deadlines

Develop principles and frameworks. In particular expansion of Recommendations:

• Y.100 GII - Scenario Development Methodology
• Y.110 GII - Principles and Framework Architecture
• Y.1001 - IP Framework
• Y.140 - Reference Point of Interconnection Framework
• Y.1241 - IP transfer capability for the support of IP-based services
• I.31y - Service orientated network requirements for B-ISDN
• I.31z - Network requirements for charging

Relationships

• All relevant ITU-T Study Groups
• ITU-R Study Groups as appropriate
• ISO/IEC, probably focused through JTC 1
• ETSI
• IETF
• Industry consortia, such as ATM Forum, etc.