Following Generation Networks NGN
BACKGROUND OF NGN
Over the last old ages, developments in telecommunication engineerings, conveying possibilities for rich context communications with multimedia content, has satisfied most of users ‘ demands about ever on, rich-content communicating ways with high grade of versatility ( conferencing, application interactivity ) . On commercial degree, all these new characteristics have been integrated within the 3G UMTS, a engineering which merely late has started being bit by bit adopted. 3GPP, the standardisation organic structure working on UMTS engineering definition has so far non merely described services classs, but defined systematically ways for presenting them with appropriate Quality of Service ( QoS ) .
Despite the outgrowth of new fixed and wireless communicating engineerings, like the WiFi, WiMAX and xDSL, with high bandwidth rates and seamless conformance to the IP, the capableness of the new UMTS engineering to bringing its services in a “measurable” manner and with user-defined QoS has been identified as the chief ground for the success of the new multimedia applications on the market. Wishing to farther feat users arisen awareness about new multimedia communicating services and spread out possibilities for new net incomes in the new fixed and wireless web spheres, the industry of communications has set a new mark, that of making “ubiquity” in service bringing along with “seamlessness” in maintaining steady the “user experience” in footings of service tariffing and QoS satisfaction. Answers to these jobs has come to give the Following Generation Networks ( NGN ) engineering, a new enterprise created jointly by ITU, ETSI and 3GPP that purposes at presenting all these new communicating characteristics on a “network agnostic” or otherwise called “heterogeneous networks” communicating environment, where the lone discriminating factors for service provisioning will be the user himself, his selected service types and the coveted QoS. In this regard, the NGN engineering shall non merely supply a individual solution for assorted web types integrating, but must reply globally, on behalf of all communicating engineerings it embraces ( fixed, Mobile, radio ) , the jobs expressed earlier about supplying service “ubiquity” and “seamlessness” , covering with issues such as, zero service break for traveling, rolling, handover users and QoS warrant among different engineering webs with diverse QoS capablenesss. Over the past few old ages, development of the NGN construct along these lines has led to the definition of the first version of a “network agnostic” communicating engineering, the IP Multimedia Subsystem ( IMS ) . IMS has become today the chief focal point of research attempts and is considered today as the enabler of the hereafter 4G, converged communicating engineering.
the Following Generation Network ( NGN ) is defined as a packet-based
web, able to supply telecommunication services over a battalion of broadband, QoS-enabled conveyance engineerings and in which service-related maps are independent from underlying transport-related engineerings. Main driver of this construct is the demand for enabling unchained entree for users to webs and to enable competition of service suppliers, which must offer their services with generalised mobility, leting consistent and omnipresent proviso to users.
The concluding purpose of NGN is to render service suppliers of any type, including those supplying Internet services, voice and multimedia content suppliers to present their services to stop users in a web and terminal agnostic manner, utilizing any device connected to any entree web. In other words, service suppliers have now the opportunity of going decoupled from the web substructure, which is now conceived as a “homogenized” heterogenous platform and therefore do usage of entree and nucleus conveyance web substructure in a liberated manner with the lone purpose to present their services to stop users with the desirable QoS. Uniting all these rules, Following coevals webs have eventually identified as web aggregation
emerging the undermentioned common features ( Figure 1 ) :
· convergence of assorted informations communicating types over the IP, i.e. informations,
multimedia, voice, picture,
· fixed, radio and nomadic web convergence,
· entree to a common set of services that can be provided over multiple entree
web types ( ADSL, UTRAN, WiFi, WiMAX, etc ) with characteristics like user
handover and roaming.
· IP-based nucleus conveyance webs,
· possibility for utilizing any terminal type ( Personal computer, PDA, nomadic telephone, set-top
boxes, etc ) ,
· seamless terminus, user and personal mobility,
· user-driven service creative activity environments,
· common set of services, admittance policies, hallmark type, ever possible web handiness regardless of the user connexion type to the web.
( Introduction to four Layers of NGN )
Architecture of NGN
? NGN adopts the hierarchal architecture
? Divided into four beds
§ Edge Access Layer
§ Core Switch Layer
§ Network Control Layer
§ Service Management Layer.
? Based on standard protocols and package shift web.
NGN Edge Access Layer ( First bed )
Bottom most bed of the NGN solution and consists of
? Multiservices Access Network ( MSAN )
- POTS telephones
- PABX ‘s
? Universal Media Gateway ( UMG )
§ Trunk media gateway
§ Mobile web gateway etc.
? Signing Gateway ( SG )
? Multiservices Access Network ( MSAN )
§ The terminal terminuss attached are
- POTS telephones
- xDSL modems for high velocity cyberspace services
- PABX ‘s connected to MSAN web on PRI/R2
? Universal Media Gateway ( UMG )
§ Supports both narrowband and package exchanging maps with multiple entree interfaces.
§ The package exchanging provides IP interface to implement service traffic procedure and transition between IP/TDM webs, which implements expeditiously the inter-working between different webs.
§ Performs the maps of
- large-scale Trunk Media Gateway ( TMG )
- Mobile web gateway etc.
? Signing Gateway
§ Independent signaling gateway to carry through the inter-working between PSTN web and NGN
§ Provides built-in STP map.
NGN Core Switching Layer ( Second Layer )
? Above Access bed lies the IP nucleus tube bed and IP Core Network bed.
? UMGs, AMGs or AGs etc. from multiple sites will be ending and meeting to their several IP Metro Core Network Layer
? IP Metro Core Network Layer connected to its several point of convergence with IP Core Network bed to complect assorted Class 5 /Class 4 and other NGN elements
NGN Network Control Layer ( Third Layer )
? The control bed is the chief shift bed of the web where all the Class 5/ Class 4 Soft switches prevarications
? It supply exchanging and signaling installation between different elements of the web like MSAN ‘s, UMGs, SHLR, IN etc.
? Soft switch
§ Soft switch is deployed in the control bed of NGN.
§ Offers an incorporate solution for both fixed and nomadic web
§ Soft switch ensures the 6H characteristics of the equipment
- High handiness
- High dependability
- High real-time
- High scalability
- High burden balance
- High conformity to open system.
§ Huawei Soft exchange Softx3000 supports upto 2 million endorsers ( at upper limit ) , with the processing capableness up to16M BHCA.
§ Soft switch
§ It acts as a generic Call Controller in the packet-switched web, supports the interworking between PSTN, H.323, SIP, and MGCP spheres.
§ Soft Switch usually provides H.248 and MGCP based carrier control.
§ Interworks with other NGN constituents through the unfastened web following distributed standard protocols.
NGN Service Management Layer ( Fourth Layer )
? It is the top most layer
? This bed is responsible for all service elements and different elements of the web like SHLR, IN Platform etc.
? The NMS besides lies at this bed and supply complete
§ Monitoring of the web.
? iManager ( integrated Network Management System ) – Nanometer
§ It uses standard protocol to pull off all devices in NGN
§ Supports end-to-end service direction
§ Provides elaborate device operation information.
§ Service constellation ( IAD dispatching and bole constellation ) is performed
§ Supports web mistake relativity analysis through dismaies.
§ Used to acquire real-time web public presentation information.
? Multimedia Resources Server ( MRS )
§ MRS provides medium resource to package web.
? Smart Home Location Register ( SHLR )
§ The SHLR is used in the public switched telephone web ( PSTN ) and NGN.
§ The SHLR provides the undermentioned maps:
? Pull offing the endorser informations.
? In SHLR, it can interpret the Logical figure into the Physical figure to implement the NP service.
§ In the NGN, the SHLR communicates with the Softswitch through the drawn-out MAP protocol
NGN engineering internals
Multimedia over Internet protocol services are available over the Internet today. These services aretypically offered by deploying a waiter that manages the session constitution between two end-points. The media flows are routed straight between the terminal user terminuss with protocols like RTP/RTCP, RSVP and IGMP used for routing and synchronising the media watercourses.
In NGN webs, real-time conversational ( e.g. video-telephony/conferencing ) and non-conversational ( e.g. video-on demand, instant messaging ) multimedia services will play a outstanding function in their success on the market. Therefore it is of import that the security, client experience and QoS perceived by paying users is much greater than that of free Internet services.
To fulfill those demands NGN funding members have devised two chief mechanisms, one for supplying control over the user Sessionss and a 2nd one for implementing the QoS scenes of the user across the end-to-end communicating way.
The first mechanism ( Figure 2 ) has been realized utilizing the SIP protocol, through which the user can be identified, authenticated and charged by the web on the footing of a individual user individuality ( IMS Personal Identity-IMPI ) . Using the SIP protocol, the user may pass on to the web information about the user he wishes to link ( called party ) , the service-of-choice every bit good as the quality scenes.
On the other side, the NGN web exploits the information of the naming party in order to implement a ) registration/ hallmark of the user on the web, B ) find the way to the called party and degree Celsius ) enforce the QoS scenes across the established way. Particularly for the latter process, the NGN web foresees a set of mechanisms dedicated to interpreting the user-requested QoS scenes to values compatible with the capablenesss of the assorted web engineerings being involved in the constitution of the end-to-end way.