2010

Antreas Artemiou

Techical Uneversity of Kosice

doc. Ing. ubomr Dobo, PhD.

Table of Contents

Introduction...............................................................................................................................3 1 NGN Description ................................................................................................................4

1.1 Basic Definition ............................................................................................................4

1.2 Developing Direction ....................................................................................................4

2 NGN Structure and Protocols............................................................................................5 2.1 NGN Structure System ..................................................................................................5 2.2 Four Function Layers ....................................................................................................5

2.2.1 Advanced Services Layer .......................................................................................5 2.2.2 Control Layer .........................................................................................................5 2.2.3 Media / Transport Layer .........................................................................................6 2.2.4 Access Layer .........................................................................................................6

2.3 Protocols Supported by NGN ........................................................................................6 2.3.1 Require Control Protocol .......................................................................................6 2.3.2 Media Gateway Controlling Protocol .....................................................................6 2.3.3 Others Protocols.....................................................................................................7

3 Technologies Supported by NGN ......................................................................................8 3.1 SoftSwitch ....................................................................................................................8

3.2 High Speed Route/Switch .............................................................................................8

3.3 Fiber Optic Transmission ..............................................................................................9 3.4 Broad Band Access .......................................................................................................9

4 NGN Services Applications .............................................................................................. 10 4.1 NGN Applications Platform ........................................................................................ 10

4.2 Services Applications .................................................................................................. 10

4.3 NGN Terminals........................................................................................................... 11

5 Conclusion ........................................................................................................................ 12

Introduction Next-generation networks are based on a genuinely innovative set of technologies that are

already transforming the way businesses communicate today, and will ultimately revolutionize how communication services are delivered in the future.

The key to this lies in the difference between what existing networks and next-generation networks have to offer. The majority of traditional voice and data networks are underpinned by multiple network platforms that employ a variety of different transmission protocols. Each of these platforms dedicates itself to supplying a single type of traffic, such as voice, data or Internet access. This mix and match approach is complex to support and expensive to scale.

1 NGN Description

1.1 Basic Definition

Next generation network (Next Generation Network, is called NGN) is one kind of emerging technology. So far, there is not a standardized organization or the authoritative organization proposes a strict definition for the NGN. So-called NGN is extremely loose definition, makes a general reference to be different with a present generation, and takes the data

as the central amalgamation. NGN is extensive concept, it contained the network which occurred to construct by multi-change ways. Believed generally that, NGN may provide the services including the pronunciation, the data and multimedia and so on.

1.2 Developing Direction NGN should be a better network than today, it will have high speed rate, support the more

services applications, and support many kinds of services application by the more comprehensive ways, it will support the different levels QoS, Movement/Maintenance/Management in NGN are simpler and more economical. The NGN network technology and the service applications, will have many and varied access and core network to serve the society; As a result of the network technology multiplicity, exchange by operating mutually becomes the main problem in future; NGN (IPv6, 3G and WDM) will use widely to provide the wide band, high grade, the safe service applications; The new communications software will drive the development of the personalization increment service; Protocols in NGN will act an important role. In brief, NGN is a very big concept, what it discusses will be correlative with everything of the future network, it doesnt only contain Internet, Mobile, IPv6, the light or the service applications, but will be all these total.

2 NGN Structure and Protocols

2.1 NGN Structure System NGN separates the switch function into many specially network modules, each part may

develops according to the corresponding function; Interfaces between connection parts bases on corresponding protocols. Its network skeleton shows like chart:

Figure 1 NGN Network Skeleton

2.2 Four Function Layers

2.2.1 Advanced Services Layer

To process service logic, its functions includes IN (intelligent network) logic, AAA (Authorization, Authentication, Accounting) and the address analysis, also develops the service applications through protocols and API.

2.2.2 Control Layer

Calling the logic, and process call request, and establish loading connection by transport layer. The core equipment of the control layer is the soft switch, the soft switch needs to support

the multitudinous protocols interfaces to realize the switching with different type networks.

2.2.3 Media / Transport Layer

It's the loading network of NGN. It is responsible to establish and manage connection to switch and route for these connections. And it needs to respond control commands from control layer. It may be the IP network or the ATM network.

2.2.4 Access Layer

It is composed of different media gateways and Integrated Access Device (IAD), and it makes different kinds of users to connect the network through various access methods, and

transforms the information format into one which can be transmitted in the packaged network.

2.3 Protocols Supported by NGN The application objects of NGN needs the standard protocols which make by ITU-T, IETF

and such as these International Standard Organization. The protocols refer NGN systems are following:

2.3.1 Require Control Protocol

SIP (Session Initiation Protocol) is made by the IETF, it is used for establishing, modification and ending the application protocols for the multimedia session, it also has the good

ability for expansion.

SIP-T (SIP for Telephones) makes the traditional telephone network signal (present only to the ISUP message) into the SIP through encapsulating and translating, and it provides an inter-connection system between the traditional PSTN and the SIP. In NGN, the SIP protocol runs between the SIP terminal and the SoftSwitch or SoftSwitch and Application Server. At the same time SIP (SIP-T) has been accepted to the interface standard and used for realizing SoftSwitch inter-connection.

2.3.2 Media Gateway Controlling Protocol

MGCP (media gateway controlling agreement) is most popular media gateway controlling protocol. Megaco/The H.248 protocol is developed by IETF and ITU-T. it bases MGCP protocol, it has provided to check media's establishment, connection, the release and guarante these signals executing system, and also carry some require signals.

2.3.3 Others Protocols

Services Layer protocols and API include SIP, PARLAY, JAIN. In order to implement the traditional intelligence network service, the SoftSwitch devices also should support the INAP protocol, and the transmit protocols based on the IP & PSTN, which have IUA, M3UA, M2PA, these signal protocols based on SCTP/IP transmission. And SNMP, COPS, RADIUS, NTP.

3 Technologies Supported by NGN NGN needs many new technologies to support. At present, NGN relating technology is:

Use the Soft Switch technology to realize the end-to-end service exchange; Use IP technology to realize amalgamation of three networks; Use the IPv6 technology for solving address problem to increase the network throughout; Use MPLS (multi- Protocols Label Switch) to realize integrating between the IP layer and many kinds of link layer protocols (ATM/FR, PPP, Ethernet, SDH, light wave),and use OTN (optical transmission network) and the optical switch network to transmit. So Soft Switch technology becomes the NGN core technology.

3.1 SoftSwitch As the NGN core technology, the SoftSwitch is a kind distributional platform basing

software. Its concept based on the new network function model (the Four Layers Module). It integrates or separates some functions. And through each kind of interface protocol the service

are possible to combine services transmission and control protocols. It is suitable to exchange in the different networks and introduce expediently into a lot of new services applications, such as the voice network to the multi- services/Multimedia network. So the SoftSwitch is also called Require Server.

3.2 High Speed Route/Switch The high speed router is in NGN transport layer to accomplish high speed route and switch

for the multimedia data stream. It is the NGN transport hinge. The NGN doesnt only do these,

but also provide better QoS than IP network presently. IPv6 and MPLS have provided this contingency. As network protocols, NGN will base on IPv6. IPv6 can expand the address space, enhance the network throughput, and improve the service quality. And the security has a better guarantee for mobility and better broadcasting. MPLS is a new technology that combines IP

routing/addressing of the third layer and high speed data switching of the second layer over network. It takes the advantage of circuit switch and exist route ways to solve many problems which exists in the current network, especially QoS and security problems.

3.3 Fiber Optic Transmission NGN needs higher speed, greater capacity. But so far, the best medium still is the light.

Because only light can bring the abundant bandwidth by the spectrum. The optical fiber high

speed transmission technology has been developing towards three directions: expanded transmission capacity of sole wave length, long distance transmission and DWDM.

Light switch and intelligence optic network: Only the high speed transmission is

insufficient, the NGN needs more flexible, the more valid light transmission network. The network now develops from light - electricity - light switch to entire light switch. The intelligent optic network has more superiority in the capacity flexibility, the cost validity, extending of the

network, and so on, compared to the point to point transmission system and the optic networking.

3.4 Broad Band Access NGN must have the broad band technical to support, because only bottleneck of the

network the bandwidth is settled, each kind of broad band service and application can develop, and potential of the network capacity can display truly. There are too many technologies developing for this. Such as VDSL, based on Ethernet Passive Optic Network (EPON&FTTH), Free Space Optical system (FSO), wireless local area network (WLAN).

4 NGN Services Applications NGN not only provides the existing telephone business and the intelligent network service,

but also may provide with the Internet applications, the multimedia service and so on. Moreover, through providing the opening connection, the service developer and the network provider may defer to the standard protocols or interfaces to provide various services. So the new services can develop rapidly.

4.1 NGN Applications Platform The unified NGN service platform provides the Centrex service, and manages all groups

users. Three levels business management control model: the WAC administrative center, the enterprise Centrex synthesis manage platform and the subscriber's business management. The service surmounts the NGN domain, the PSTN domain and the Mobile domain. To provide the custom-made services for each user group. As following chart:

Figure 2 NGN service platform provides the Centrex service

4.2 Services Applications 1. PSTN/ISDN voice service, standard supplement service, CENTREX service and

intelligence service.

2. Based Internet service: Click to dial, WEB 800, Instant Messaging, Synchronized browsing, the personal communication management.

3. Multimedia desktop video calling/Conference services, coordination application,

stream media service.

4.3 NGN Terminals NGN can exchange with existing networks such as PSTN, ISDN and GSM and so on. NGN

may interconnect the existing networks and keep exist investment safely through some devices

such as the gateway. At the same time, NGN also supports the exist terminals and the IP intelligence terminal, including the simulated telephone, electrograph, the ISDN terminal, the mobile phone, the GPRS terminal, the SIP terminal, the H248 terminal, the MGCP terminal, Ethernet telephone through the PC, the video phone, the cable modem and so on. You can see

them in picture following:

Figure 3 NGN exchange with existing networks

5 Conclusion With the development and maturation of the technologies, the protocols, the products, the

network operation, the network switching for simplex data has not been able to reach people's need. 3G integration becomes the mainstream of the network development. Believe that in the

near future, NGN can become the network construction mainstream inevitably.