![](bg2.png)
requires a stable quality of service and the changing of sharing relationship can never
happen frequently. There are many technical concerns that are addressed to produce ef-
fective grid computing. This may include information services, security, scheduling and
resource management, performance, remote data access and archiving, and program-
ming model. To this end, the model works for a conventional distributed environment
but is challenged in the highly variational wireless mobile environment.
With the growing demand for mobile data services, novel value-added services and
content provisioning will be the driving force behind the development and deployment
of future communication networks and mobile Internet. As the Internet evolves and ex-
pands to include next-generation, data-enabled mobile devices, it is important to make
data services available on these devices rapidly. It is essential to enable quick and flex-
ible development and deployment of end application functionality. Such functionality
should be enabled in the presence of a wide variety of heterogeneous access networks.
Service mobility is the feature where the user can access the same set of services seam-
lessly, independent of the access network and the access device. To achieve this, it is
necessary to personalize and adapt content to end-user devices with varying capabili-
ties. Thus we consider the idea of composition.
Service Composition refers to the construction of complex services from primitive
ones, thus providing rapid and flexible creation of new services. Fixed broker-based
or fixed central-entity based service composition techniques cannot be applied as a
solution to compose services on the fly as the clients can be mobile. The client may also
use a service which may be mobile and connected through wireless network. This is due
to the fact that such approaches presuppose the existence of a persistent central entity or
coordinator in the clients neighbourhood, which is reliable and constantly available on
request. Thus service composition can be defined as a dynamic integration of multiple
services available in an mobile grid environment in response to a request from a client.
The proposed research intends to study the key issues involved in building a middleware
for service composition in a dynamic distributed mobile computing environment, and
comes out with a layered architecture for the infrastructure of such a model.
The rest of the paper is organized as follows: section 2 gives a overview of the
related work. Section 3 gives the implication of integrating mobile devices into the grid.
Section 4 gives an overview of the proposed approach, that includes the motivation,
design issues and principles. Section 5 describes the layered architecture of the service
composition middleware architecture for mobile grid and in section 6 we conclude.
2 Related Work
In mobile environment, networks are unstable, mobile nodes can join and leave fre-
quently. The quality of connection is unpredictable, even network itself can be ad-hoc.
Moreover, mobile nodes have limited local resources and battery life. Although grid
computing hasn’t addressed these problems extensively, research in mobile computing
provides solutions attacking these mobility issues. There are few infrastructures like
Legion Grid computing infrastructure [5] that has come up to support resource het-
erogeneity ranging from supercomputers to small, handheld devices. There are many
issues regarding mobile and wireless computing that are only solved in an application-
40