Arrangement for improving availability of services in a communication system

Description of equivalent WO 9845987 A2

ARRANGEMENT FOR IMPROVING AVAILABILITY OF SERVICES IN A COMMUNICATION SYSTEM

FIELD OF THE INVENTION

The present invention relates to an arrangement for improving availability of services in a communication system, especially a telecommunication system, said system comprising distributed hardware and software components which interact in order to provide services to one or more users .

BACKGROUND OF THE INVENTION

The rapid expansion of digital cellular telephone expresses an urgent demand for mobility from the users and the necessity of the mobility support for telecommunication systems. Both ODP and TINA-C define the mobility support as an important requirement. However, both ODP and TINA-C assume in their original framework that the support of mobility is considered as a consequence of the support of the other distribution transparencies and, therefore, does not require any additional functions and mechanisms in the Distributed Processing Environment (DPE) .

The present invention has been developed on the basis that access and location transparencies are not sufficient for supporting terminal and personal mobility. The main development of the present invention is based on considering mobility as an additional transparency and in order to do so there is according to the present invention proposed a Functional Separation Architecture wherein the mobility functions are separated from the network layer and the application (service) layer and grouped into a separate layer called the mobility layer.

The present invention has for its main object to suggest an implementation of realising such mobility layers, especially in connection with a so-called Generic Mobility System (GMS) , whereby such a GMS will be designed and then introduced in the architecture transparency, i.e. applications although supported by the GMS are not aware of its existence.

STATE OF THE ART

The existing development environments and platforms for distributed systems such as for example CORBA [Objb] do not address mobility. In order to design mobile applications, i.e. applications that are available for mobile users, the application designer must consider, design and implement all the necessary mobility functions. This is avoided by using the GMS.

PROBLEMS RELATED TO PRIOR ART

The design and implementation of mobile applications are quite difficult since the application must deal with the mechanisms and function related to mobility which are complex, numerous and also time-consuming to implement. Further, the implementation of mobility functions by different persons for different applications at different places may lead to conflict and unwanted interactions.

On the other hand, quite a lot of efforts are required to make existing fixed-applications mobile. OBJECTS OF THE PRESENT INVENTION

An object of the present invention is to propose a Generic Mobility System incorporating all the mechanisms and functions necessary to support mobility.

SUMMARY OF THE INVENTION

The above objects are achieved in an arrangement as stated in the preamble, which according to the present invention is characterised by the features as stated herein and specifically in the enclosed patent claims.

Further features and advantages of the present invention will appear from the following description taken in conjunction with the appending drawing.

BRIEF DISCLOSURE OF THE DRAWING

Figure 1 is a schematical diagram illustrating an embodiment of the present invention, especially the Generic Mobility System and its functions.

DESCRIPTION OF EMBODIMENTS

This invention consists of a Generic Mobility System (GMS) which provides all the mobility support functionality for any type of networks and distributed systems.

The GMS encapsulates all the functions needed to support mobility, i.e. all the processing and data management necessary to support the mobility of the users and terminals are taken care of by the GMS. The GMS is generic in the sense that it is applicable to all the telecommunications systems. The flavour of the wanted mobility can be combined and configured at installation. A telecommunications system, public or private, can choose, adopt, customise and instantiate every component of the GMS to obtain a mobility system supporting the type of mobility required. One instance of the GMS may for instance support only discrete terminal mobility suitable for a DECT system while another instance may support all types of mobility, i.e. terminal, user and session mobility. The service applications of the telecommunications system can then in turn choose and subscribe to the services of the mobility system.

The GMS can be implemented as a middleware, i.e. off-the- shelf software which can be purchased and installed in any distributed system such as CORBA-based (Common Request Broker Architecture) systems [Objb] to support mobility.

A more specific embodiment of such a Generic Mobility System (GMS) will now be described in detail reference being had to the enclosed Figure 1.

As shown in Figure 1 the Generic Mobility System will have the following fundamental functions:

• Terminal Mobility comprising functions and mechanisms to support terminal mobility at object communication level.

• User Mobility comprising functions and mechanisms to support user mobility at object communication level. • Mobility Transparency Support comprising functions and mechanisms to make mobility transparent at object communication level.

• Mobility-related Security comprising functions and mechanisms to handle the mobility-related security issues .

• Mobility-unaware Application Support comprising func- tions and mechanisms to support and make mobility transparent to the application considered an entire unit of activity.

• Session Mobility comprises functions and mechanisms to support session mobility.

• Mobility-aware Application Support comprising functions and services offered to the mobility-aware applications .

• Mobility-based Application Support comprising functions and services offered to the mobility-based applications .

It is important to emphasise that the given overview of the GMS shows only a classification of the GMS functions. It is not a decomposition of the GMS into groups of objects . MERITS OF THE INVENTION

• The GMS will alleviate the design and implementation of mobile applications and allow fixed-applications to be mobile without modification.

• The GMS addresses a wide range of communications systems, public or private, local-area or wide-area, wireline or wireless.

• The GMS can be customised to support any combination of mobility, such ad discrete terminal mobility, personal mobility, session mobility, etc.

• The GMS can run in any existing distributed platforms such as CORBA, JAVA, etc.

IMPORTANT FEATURES OF THE PRESENT INVENTION

Important features of the present invention are as listed in the following:

• A module or package called Generic Mobility System is introduced to give mobility support in distributed sys- tern.

• Such a GMS contains the following mobility support functions: terminal mobility support functions, user mobility support functions, session mobility functions, mobility transparency support functions, mobility- related security functions, mobility-unaware application support functions, mobility-aware application support functions, mobility-based application support functions . • Such a GMS offers the possibility to choose, select, customise and combine any of the mentioned functions as desired.

• Such a GMS can be installed and used in any type of communication system, public or private, local -area or wide-area, wireline or wireless.

• Such a GMS can be implemented as middleware, i.e. off- the-shelf software which can be purchased and installed in any distributed environment and platform such as CORBA-based (Common Request Broker Architecture) systems [Objb] .

REFERENCES

[Objb] Object Management Group, Inc. The Common Object Request Broker: Architecture and Specification. Revision 2.0, July 1995.