ELOQUENCE11 A TECHNICAL PAPER PRESENTATION ON MOBILE COMPUTING

M.V.DEEPTHI A.HARIKA 08121A1221 08121A1204 (3/2).B.Tech (3/2).B.Tech [email protected] [email protected]

SREE VIDYANIKETHAN ENGINEERING COLLEGE

SREE SAINATH NAGAR, TIRUPATI-517 102. Abstract analysis of current mobile service architecture such as voice With the advent of the Internet and the communication, supplementary services plurality and variety of fancy with intelligent network, enabling applications it brought with it, the services on SIM with SIM application demand for more advanced services on tool kit, text services with short message cellular phones is increasingly becoming service, internet services with WAP and urgent. Unfortunately, so far the dynamic applications on mobile phones introduction of new enabling with J2ME. technologies did not succeed in boosting new services. The adoption of Internet Further our paper gives services has shown to be more difficult information on challenges of mobile due to the difference between the computing which includes harsh Internet and the mobile communications, connections, telecommunication system. The goal of bandwidth and heterogeneous this paper is to examine the networks. Under research issues characteristics of the mobile system and seamless connectivity over multiple to clarify the constraints that are overlays, scalable mobile processing, imposed on existing mobile services. wireless communications, mobility and The paper will also investigate portability are discussed. successively the enabling technologies and the improvements they brought. Most importantly, the paper will identify their limitations and capture the fundamental requirements for future mobile service architectures namely openness, separation of service logic and content, multi-domain services, personalization, Personal Area Network (PAN)-based services and collaborative 1. Introduction services. The paper also explains the With digitalization the difference between telecommunication and computer net-working is fading and the components represented by grey ovals same technologies are used in both that are distributed both on the mobile fields. However, the convergence does phone, also called Mobile Station (MS) not progress as rapidly as expected. and on the mobile network. On the MS, Moving applications and ser-vices from there are components both on the Mobile one field to the other has proven to be Equipment (ME) and on the subscriber very difficult or in many cases Identity Module (SIM). To establish a impossible. The explanation is that telephone conversation the service although the technologies in use are components on the MS are collaborating rather similar there are crucial with the ones on the mobile network to differences in architecture and concepts. allocate a channel and to maintain it The paper starts with a study of how throughout the session even when the mobile services are implemented in MS is moving and changing base mobile telecommunication systems and stations. The components on the mobile an identification of their limitations so as phone are installed by the manufacturer to meet the future needs of the future. while the ones on the network are delivered by network suppliers. 2. Analysis of current mobile service architectures 2.2 Supplementary services with 2.1 Voice communication intelligent network

As indicated by its name, the objective It does not take long time before there of mobile telecommunications systems is is a need for more advanced call control to provide communication between ser-vices like call forwarding, barring, mobile distant persons. These systems voice mail, premium call, etc. As shown only supported direct voice in Figure 3 an IN (Intelligent Network communication or telephony between [1]) Service Control Point (SCP) is two participants, but supplementary introduced in the mobile network to services like call forwarding, barring and allow the implementation of voice mail were added later on. The supplementary services. It is worth mobile telephony service is realized by mentioning that these services are derivatives centered around the voice applications/services residing on the communication service. Another SIM to control the input and output restriction is that the SCP is units. With SAT it is possible to develop implemented on equipment applications on the SIM but there are manufacturer proprietary technologies. many restrictions. First SAT applications The SCP is also located inside the should be small in size. Secondly, the telecom operator domain making third installation of applications on the SIM is party service development difficult. controlled by operators who are reluctant to open the access due to security. 2.4 Text services with Short Message Service (SMS)

SMS-C is responsible to store and forward messages to and from mobile phone (see Figure 3). In the illustration, components used for SMS are the client (C) in the ME advanced SMS services are implemented by perlscripets. 2.3 Enabling services on the SIM Provisioning of SMS services requires with SIM Application Toolkit installation of the above mentioned (SAT) application on an SMS Gateway the The telecom operators want to have system running the SMS Gateway to act other services than telephony and its as an SMSC itself (e.g. a PC using a derivatives and turn to the SIM, which radio modem through a serial port). To are their property. Unfortunately, have direct access to an SMSC requires although the SIM is a smart card having cooperation with the operator that owns both processing and storage capabilities the SMSC, which often can provide a necessary for new services. The SIM is TCP connection for sending/receiving supposed to be the slave executing SMS messages part of a service. The orders from its master, the ME. To advantage of the above solution is that to remedy this, the SIM Application Tool- receive revenue from generated traffic. kit (SAT) [2] is introduced to allow The problem with access to SMS services is remembering both the service 12.6 Dynamic applications on access number and the additional mobile phones with J2ME identifiers and parameters for a specific (CLDC/MIDP) service (the protocol) 2.5 Internet access with WAP Unlike a computer, the functionality of Wireless Application Protocol (WAP) the mobile phones is defined at [5] was to provide access to the WWW manufacture time and it is not possible on handheld terminals. A micro browser to install new applications. With installed in the Mobile Equipment is introduction of the J2ME CLDC/MIDP communicating with a WAP Proxy vast amount of sophisticated introduced between the Internet and the applications, called MIDLETS can be mobile network to convert Internet found on the Internet. With J2ME, it is protocols to Wireless binary protocols as possible to develop dynamic standalone shown in Figure 3. On the terminal side, applications. When it comes to SMS, a WAP browser is located in the ME and there are still some restrictions in J2ME, services are connected to a Web server such as access to the standard inbox for on the network side. development of SMS messages on a handset is not WAP services can be performed by allowed. programming experience. Most services Process, the “write-once-run-anywhere” typically consist of some static WML concept is not valid for this platform. content together with a CGI-script as through the Most Integrated back-end that can generate dynamic Development Environments (IDE) for content retrieved from for example other Java allows development of J2ME Web sites or from a DBMS. One applications as well. Although J2ME is a restriction of the technology is that it is standardised technology, performed Java not possible to access ordinary webpages Community using a WAP browser. 3. Advanced Architecture This section aims at identifying and elucidating the advanced pieces and hence contribute to the definition of Considering a service as consisting of advanced architecture. two components, service logic and 3.1 Separation of service content service content, makes the analysis and logic easier. In early mobile telecom services the service logic was Mobility is the ultimate embedded in the dedicated hardware requirement for mobile services. The components. This has been a hindrance mobility properties of a service are for development of flexible services, dependent on the architecture and these services will by default not be particularly on the location of the accessible from outside an operator components making up the service. domain. To enhance the mobility of will cooperate in delivering the end user service. ser-vices, it is necessary to decouple the service logic from the system components.

3.2 Multi-domain services

By using this service we cannot only 3.3 PAN-based Services access all services provided by the network but also many users can work at Nowadays, each individual is using the same time. Mobile services will be several devices like mobile phones, provided as distributed services where PDA’s, digital camera, GPS, etc. With the logics residing in different places the emergence of wireless short-range technologies like Bluetooth, WLAN and potentially, Personal Area Networks can be formed to allow communication between devices. 4.Challenges of Mobile Computing:

3.4CollaborativeServices

With a multi-domain service, it will be possible for people not only to Freedom from Collocation collaborate across network boundaries, but also across terminal boundaries. • Harsh communications environment.

The unfavorable Communication environment is coupled with Lower bandwidth/higher latency not good enough for videoconferencing or any other process. It has higher error rates and more frequent disconnection. Its performance depends on density of It is also possible for several people to nearby users but inherent scalability of collaborate by exchanging information cellular/frequency reuse architecture through several channels and devices helps. simultaneously such as talking on the • Connection/Disconnection: phones, showing picture on digital cameras, reading documents on PDA’s. Network failure is a common issue and therefore Autonomous operation is highly desirable. Fot it often Caching is a good idea, e.g., web cache. Asynchronous/spool – oriented applications, like mail or printing do have some problems .In those cases Trickle back data when bandwidth is available. • Low Bandwidth – Orders of magnitude differences between wide-area, in building wireless • Variable Bandwidth – Applications adaptation to changing quality of connectivity » High bandwidth, low latency: business as usual » High bandwidth, high latency: aggressive prefetching » Low bandwidth, high latency: asynchronous operation, use caches to hide latency, predict future references/trickle in, etc. • Heterogeneous Networks – “Vertical Handoff” among collocated wireless networks 5.Research Issues • Seamless connectivity over multiple overlays – Implementing low latency handoffs – Exploiting movement-tracking and geography – Performance characterization of channels – Authentication, security, privacy • Scalable mobile processing – Hierarchical and distributed network management – Load balancing for network mgmt & application support 6. Conclusion – Integration with local- & wide-area This paper presents an analysis of the networked servers evolutionary path of mobile services, --Application support for adaptive from early voice communication connections services to prospects of future service Wireless Communications possibilities. It is argued that increasing – Quality of connectivity openness can help excel the future of – Bandwidth limitations mobile services. Each of the concepts • Mobility discussed around mobile services in this paper are on their own and of research – Location transparency and they must be further elaborated in --Location dependency separate studies. Thus, the discussions in • Portability this paper are preliminary and do address – Power limitations only the basic structures and further --Display, processing, storage limitations works will be carried out. 5. References 1. Gunnar Heine, GSM Networks: Protocols, Terminology and Implementation. 2. http\\:www.iitd.ac.in 3. ETSI, Digital cellular telecommunications system (Phase 2+);Specification of the SIM Application Toolkit (SAT) for the Subscriber Identity Module.

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