1. NEXT GENERATION
NEXT GENERATION
NETWORKS (NGN) AND IMS
NETWORKS (NGN) AND IMS
• What is NGN?
• Need for NGN
• Objectives of NGN
• Fundamental characteristics of NGN
• Challenges of NGN
• Architecture of NGN
• IP Multimedia Subsystem (IMS)
Hafeth Dawbaa 228/2009
2. What is NGN?
• A Next Generation Network (NGN) is a packet-based
network able to provide Telecommunication Services to
users and able to make use of multiple broadband, QoS-
enabled transport technologies and in which service-
related functions are independent of the underlying
transport-related technologies. It enables unfettered
access for users to networks and to competing service
providers and services of their choice. It supports
generalized mobility which will allow consistent and
ubiquitous provision of services to users.
ITU-T REC. Y.2001 (12/2004)
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3. • The next-generation network (NGN) is body of key
architectural changes in telecommunication core and
access networks. The general idea behind the NGN is that
one network transports all information and services (voice,
data, and all sorts of media such as video) by
encapsulating these into packets, similar to those used on
the Internet. NGNs are commonly built around the
Internet Protocol, and therefore the term all IP is also
sometimes used to describe the transformation toward
NGN.
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4. Main architectural changes that NGN
involves
• In the core network, NGN implies a consolidation of several
(dedicated or overlay) transport networks each historically built
for a different service into one core transport network (often
based on IP and Ethernet). It implies amongst others the
migration of voice from a circuit-switched architecture (PSTN)
to VoIP, and also migration of legacy services such as X.25,
frame relay (either commercial migration of the customer to a
new service like IP VPN, or technical emigration by emulation
of the "legacy service" on the NGN).
• In the wired access network, NGN implies the migration from
the dual system of legacy voice next to xDSL setup in local
exchanges to a converged setup in which the DSLAMs
integrate voice ports or VoIP, making it possible to remove the
voice switching infrastructure from the exchange.
• In the cable access network, NGN convergence implies
migration of constant bit rate voice to CableLabs PacketCable
standards that provide VoIP and SIP services. Both services ride
over DOCSIS as the cable data layer standard.
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7. Objectives of NGN
• promote fair competition
• encourage private investment
• define a framework for architecture and capabilities to be
able to meet various regulatory requirements
• provide open access to networks
• ensuring universal provision and access to services
• promoting equality of opportunity to the citizen
• promoting diversity of content, including cultural and
linguistic diversity
• recognizing the necessity of worldwide cooperation with
particular attention to less developed countries
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8. Fundamental characteristics of NGN
• packet-based transfer
• decoupling of service provision from transport
• support for a wide range of services
real time, streaming, non-real time and multimedia
• broadband capabilities with end-to-end QoS
• generalized mobility
• The ability for the user or other mobile entities to communicate
interworking with legacy networks via open interfaces
• and access services irrespective of changes of location or
unrestricted access by users to different service of location or
and access services irrespective of changes providers
technical environment. The degree of service availability may
……
• converged services between fixed/mobile
depend on several factors including Access Network
• capabilities, service level agreements between the user's
independence of service-related functions from underlying
transport technologies visited network (if applicable), etc.
home network and the
• support of multiplethe ability of telecommunication with or
Mobility includes last-mile technologies
without service continuity.
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10. Challenges of NGN
• The quality of service (QoS)
• The management challenge
• The transition challenge
• The security challenge
• The economic challenge
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