The continuously increasing Internet coverage and its availability has give rise to an issue that was once considered not important to take into consideration. Today a number of applications use the Internet to de-liver time critical messages. The usage of wireless Access Points involves a considerable percentage to connect mobile devices to the Internet pro-vider. However, these relatively cheaper Internet Access Points have their own disadvantages as compared to the GSM and ADSL. The access points cover a very limited area and thus in order to cover a wider area multiple access points must needs to be installed. In other words, as the user moves he/she is supposed to switch between access points. Never-theless, the basic problem in such cases is involves packet loss during handover. In today’s technological advancements these issues, though very small, are no more insignificant but are required to be handled prop-erly. So protocols such as MobileIP, LISP, HOST have been proposed and are currently being used for such a purpose. Furthermore, in this thesis a mechanism to reduce such packet losses has been studied and proposed in relation to the SensibleThings Internet-of-things platform. A workaround solution known as Mobile DCXP has been proposed and implemented and comparisons with the existing system have been carried out. In addition, a generic solution has been discussed in detail and compared with the Mobile DCXP. However, the implementation of the generic solution has been deferred to the future. The concept of Mobile DCXP has been illustrated with proof-of-concept apps and an implementation of a simple Android Application known as IChat has been conduct. The IChat is a simple chat app that is used in the experi-ment to determine out the packet lost during handover and to carry out a comparison. Finally, based on the data collected from IChat, an evaluation of Mobile DCXP has been presented and a performance comparison with Mobile Proxy DCXP has been illustrated with charts. Furthermore, in the conclusion Mobile DCXP could minimize packet loss as compared to the existing system.

<p>The convergence of future networks relies on the evolution of technology that enables seamless roaming abilities across non-heterogenous networks for mobile clients. This thesis presents an experimental study of a GPRS-WLAN integration scenario where the objective is to analyze various aspects of the issues related to charging, mobility, roaming and security between GPRS and WLAN networks. The mainly discussed integration scenario in this thesis is loosely coupled systems working on RADIUS platforms, which together with MobileIP and IPSec provides the mobile client with a secure and access-technology independent network access platform. </p><p>In order to accommodate GPRS client authentication for WLAN operators, there is a prominent need for the incorporation of necessary GPRS functionality into present AAA servers. RADIUS has been studied as the initial target for the implementation of a GPRS interface towards SMS-Cs and HLRs.The authentication of a mobile client is performed against a HLR/AuC in a GPRS network, either over SS7 links or through the incorporation of SIGTRAN protocols over SCTP. SIGTRANsolutions has the ability to join WLAN networks in a SS7 resource sharing model where the SS7 authentication signalling traffic is transported over IP networks to a Signalling Gateway acting as the logical interface against SS7 networks. </p><p>GPRS-WLAN accounting may be solved through direct roaming agreements between mobile operators and in such a case transport CDR’s over FTP between their billing systems. If roaming agreements does not exist, it may be viable to establish relationships between WLANs and brokers as well as mobile operators and brokers. The brokering model provides a scalable model that allows easier exchange of charging and billing information on an infrastructure based on WLAN and GPRS billing systems. Standardised transmission protocols for accounting information such as GTP’/TAP3 may be utilised in order to provide a generic billing exchange format between billing systems and operators. </p><p>Furthermore, different network architectures may have different requirements in order to accommodate GPRS clients with WLAN access. A few network architectures has been analysed, and the developed GPRS AAA Interface Daemon (GAID) has been put into context in order to present a generic GPRS-WLAN systems integration solution for WLAN operators. </p><p>The analysed solutions in this thesis give various possibilities for WLAN operators to setup wireless services for bypassing mobile clients. The implementational work provides a RADIUS platform, which can be enhanced with functionality that enables communication over any interface in the future.</p>

The convergence of future networks relies on the evolution of technology that enables seamless roaming abilities across non-heterogenous networks for mobile clients. This thesis presents an experimental study of a GPRS-WLAN integration scenario where the objective is to analyze various aspects of the issues related to charging, mobility, roaming and security between GPRS and WLAN networks. The mainly discussed integration scenario in this thesis is loosely coupled systems working on RADIUS platforms, which together with MobileIP and IPSec provides the mobile client with a secure and access-technology independent network access platform. In order to accommodate GPRS client authentication for WLAN operators, there is a prominent need for the incorporation of necessary GPRS functionality into present AAA servers. RADIUS has been studied as the initial target for the implementation of a GPRS interface towards SMS-Cs and HLRs.The authentication of a mobile client is performed against a HLR/AuC in a GPRS network, either over SS7 links or through the incorporation of SIGTRAN protocols over SCTP. SIGTRANsolutions has the ability to join WLAN networks in a SS7 resource sharing model where the SS7 authentication signalling traffic is transported over IP networks to a Signalling Gateway acting as the logical interface against SS7 networks. GPRS-WLAN accounting may be solved through direct roaming agreements between mobile operators and in such a case transport CDR’s over FTP between their billing systems. If roaming agreements does not exist, it may be viable to establish relationships between WLANs and brokers as well as mobile operators and brokers. The brokering model provides a scalable model that allows easier exchange of charging and billing information on an infrastructure based on WLAN and GPRS billing systems. Standardised transmission protocols for accounting information such as GTP’/TAP3 may be utilised in order to provide a generic billing exchange format between billing systems and operators. Furthermore, different network architectures may have different requirements in order to accommodate GPRS clients with WLAN access. A few network architectures has been analysed, and the developed GPRS AAA Interface Daemon (GAID) has been put into context in order to present a generic GPRS-WLAN systems integration solution for WLAN operators. The analysed solutions in this thesis give various possibilities for WLAN operators to setup wireless services for bypassing mobile clients. The implementational work provides a RADIUS platform, which can be enhanced with functionality that enables communication over any interface in the future.

The purpose of the Walkstation II project is to create a testbed for a wireless communication system with access to the Internet. The Mobile INTernet (MINT) router is a core element of this project. Most of the routers and many other nodes of today's Internet support network management. This includes the remote control of various parameters which caracterize the status of physical interfaces, protocols and many other objects. The Simple Network Management Protocol (SNMP) which was used in the current work is a standard protocol of the TCP/IP suite. All the managed nodes of the Internet have a common set of management capabilities. Their implementation is available in software development packages. The management of mobile stations requires a new set of management capabilities. They will allow for the control of mobility support and the radio links. The current work consists in adapting the set of standard SNMP capabilities to the MINT router and of the creation of a set of new capabilities specific to the MINT. / <p>I do not know the number of university credits, but entered it as 30 ECTS. This was an exchange student and I do not know if they were actually registered at KTH.</p>

<p>Text communication is often perceived as lacking some components of communication that are essential in sustaining interaction or conversation. This interaction incoherency tends to make&nbsp / text communication plastic. It is traditionally devoid of intonation, pitch, gesture, facial expression and visual or auditory cues. Nevertheless, Instant Messaging (IM), a form of text communication is on the upward uptake both on PCs and on mobile handhelds. There is a need to rubberise this plastic text messaging to improve co-presence for text communications thereby improving&nbsp / synchronous textual discussion, especially on handheld devices. One element of interaction is gesture, seen as a natural way of conversing. Attaining some level of interaction naturalism&nbsp / requires improving synchronous communication spontaneity, partly achieved by enhancing input mechanisms. To enhance input mechanisms for interactive text-based chat on mobile devices,&nbsp / there is a need to facilitate gesture input. Enhancement is achievable in a number of ways, such as input mechanism redesigning and input offering adaptation. This thesis explores affective gesture mode on interface redesign as an input offering adaptation. This is done without a major physical reconstruction of handheld devices. This thesis presents a text only IM system built on&nbsp / Session Initiation Protocol (SIP) and SIP for Instant Messaging and Presence Leveraging Extensions (SIMPLE). It was developed with a novel user-defined hotkey implemented as a one-click context menu to &ldquo / fast-track&rdquo / text-gestures and emoticons. A hybrid quantitative and qualitative approach was taken to enable data triangulation. Results from experimental trials show that an&nbsp / Affective Gesture (AG)approach improved IM chat spontaneity/response. Feedback from the user trials affirms that AG hotkey improves chat responsiveness, thus enhancing chat spontaneity.</p>

<p>Text communication is often perceived as lacking some components of communication that are essential in sustaining interaction or conversation. This interaction incoherency tends to make&nbsp / text communication plastic. It is traditionally devoid of intonation, pitch, gesture, facial expression and visual or auditory cues. Nevertheless, Instant Messaging (IM), a form of text communication is on the upward uptake both on PCs and on mobile handhelds. There is a need to rubberise this plastic text messaging to improve co-presence for text communications thereby improving&nbsp / synchronous textual discussion, especially on handheld devices. One element of interaction is gesture, seen as a natural way of conversing. Attaining some level of interaction naturalism&nbsp / requires improving synchronous communication spontaneity, partly achieved by enhancing input mechanisms. To enhance input mechanisms for interactive text-based chat on mobile devices,&nbsp / there is a need to facilitate gesture input. Enhancement is achievable in a number of ways, such as input mechanism redesigning and input offering adaptation. This thesis explores affective gesture mode on interface redesign as an input offering adaptation. This is done without a major physical reconstruction of handheld devices. This thesis presents a text only IM system built on&nbsp / Session Initiation Protocol (SIP) and SIP for Instant Messaging and Presence Leveraging Extensions (SIMPLE). It was developed with a novel user-defined hotkey implemented as a one-click context menu to &ldquo / fast-track&rdquo / text-gestures and emoticons. A hybrid quantitative and qualitative approach was taken to enable data triangulation. Results from experimental trials show that an&nbsp / Affective Gesture (AG)approach improved IM chat spontaneity/response. Feedback from the user trials affirms that AG hotkey improves chat responsiveness, thus enhancing chat spontaneity.</p>