Motivation

The desire to support services¹ within networks using IP technology has resulted in a number of architectural solutions being worked on in numerous standardization bodies and fora;

These solutions are either specific to a particular type of access network or are limited to a particular category of services (e.g. voice over IP or conversational services), or do not provide sufficient details on the control plane;

A standardized architectural model for a control plane that is independent of, yet takes account of, various access mechanisms (e.g. various forms of DSL, mobility air interfaces, traditional local loop technologies, etc.) is needed.

A standard reference model for the NGN control plane is required to identify a set of physical interfaces for which interoperability between networks and between equipments from different suppliers is required;

Fixed/mobile core network convergence is an important objective for NGN because it complements the “access independence” requirements.

As the ITU-T has led and continues to lead the development of the PSTN/ISDN and Packet-based public networks, including services and control protocols, it is believed that the ITU-T is the most suitable body to develop the signalling requirements for NGN architectures.

Note – In this context the notion of control plane should be understood as the set of functionalities required to control network attachment procedures (including mobility management and authentication), to control session establishment and release, to control bearer resources (including Quality of Service control), to interact with services and applications and to interact with legacy networks.

Recommendations in force for which the Question is responsible: Q.3030

Question

Study items to be considered include, but are not limited to:

• What enhancements to the signalling and control architecture are required to model the control plane of Next Generation Networks, taking into account multimedia services (conversational and non-conversational) and all types of wire-line and wireless public access networks over which these services may be delivered?
• What signalling and control architecture and entities are required to assure security of signalling and control?
• What enhancements to the signalling and control architecture are required to support services and/or applications of public interest such as emergency call handling, number portability, etc.?
• What enhancements to existing Recommendations are required to provide energy savings directly or indirectly in information and communication technologies or in other industries? What enhancements to developing or new Recommendations are required to provide such energy savings?

Tasks

Tasks include but are not limited to:

• Determine the requirements that the generic, access-technology-independent functional NGN signalling control architecture is intended to support. It is anticipated that these requirements will need to be periodically refined to reflecting the evolution of telecommunications and computer communication technologies taking into consideration the signalling control architectures available from ITU-T and other SDOs.
• Identify modifications and enhancements to the signalling control architecture that will enable that architecture to meet the requirements of the NGN functional architecture.
• Identify a set of physical interfaces for which interoperability between different network equipment is desirable and for which detailed signalling requirements need to be studied and control protocols need to be standardized.
• Study the application of generic signalling control architecture to a range of wire-line, optical and wireless access network technologies e.g. DSL, PON, W-CDMA, etc.
• Identify security requirements in support of the overall security framework.
• Define interworking with legacy systems.
• Study specific signalling control architectures such as peer to peer architectures.

Relationships

Recommendations:

• Y.2012.

Questions:

Questions responsible for:

• application control and signalling (2/11).
• session control and signalling (3/11).
• bearer control and signalling (4/11).
• resource control and signalling (5/11).
• network attachment control and signalling (7/11).

Study Groups:

ITU-T study group(s) responsible for:

• voice and video IP application over cable television networks.
• principles, requirements, frameworks and architectures for an overall heterogeneous network environment.
• multimedia architecture.
• IMT2000 and Beyond.
• security framework.

Standardization bodies:

Organizations such as: 3GPP (via ETSI) and 3GPP2 (via TIA), ASTAP (Asia-Pacific Telecommunity Standardization Program), ATIS (Alliance for Telecommunications Industry Solutions), ATM Forum, DSL Forum, ETSI, IETF, MSF, W3C, OASIS.

¹The word “service” in this context is not meant necessarily to represent an ITU-T-defined Service.