IKANGAI Solutions. e.u.

In our working scenario, we look at the creation of a presentation for a keynote at an archeological conference. The speaker, being a university professor, wants to give an overview on the current work of his group and highlight some of the recent findings. He decides to show the recent activities of his group with short videos from excavation sites during the keynote. Thus, the professor asks his co-workers to provide him some of their material so that he can include it in the presentation. Being an archeological group, several team members are working in the field and are not available in the office for a direct consultation. Thus, they need to be reached via email, text message or phone call. Remote team members also need to be reminded not to forget to produce their input for the presentation, because they do not necessarily have their laptops around when working on the excavation site.

After the collection of the video material is completed, the material needs to be edited according the needs of the professor for his keynote. For this purpose, the university provides a video editing service which takes the raw video material, a description of the desired outcome (duration, resolution, deadline) and produces a new video. This activities can be iterated over several steps to produce the final version of the video. Finally, the professor can make a reservation for a presentation room to practice his keynote to ensure that his laptop works with projectors and ask colleagues for feedback on his presentation.

If we treat the application scenario as Service composition/Service coordination problem, we can observe that there are several challenges that are difficult to address with existing approaches. First of all, we need to integrate different types of services into a Service composition. In our scenario, we have human provided Services like the recording the video on the excavation site and the video editing service. The location based reminder Service is embodied as App on mobile devices, as well is the video upload Service. The reservation consists of making a phone call and inviting colleagues to the trail keynote talk requires contacting them via email or phone. Secondly, the group working remotely requires asynchronous communication, because the not every person at the excavation sites may be reachable all the time. Thirdly, the inclusion of the social context needs to be addressed as well. Horowitz discussed this aspect as the village paradigm. In villages, knowledge dissemination is achieved socially: information is passed from one person to another person, and eventually the right person is found who is able to answer a particular question. In our scenario, we can make use of the very same paradigm, but our focus on the discovery of Apps. A typical conversation could be imagined as follows:

Person A: Do you know a tool to upload videos to our site?
Person B: Well, let me think \dots I know that C has a tool on his mobile that you could use. Ask him!
Person A: (asking C): B told me, you have a tool for video upload?
Person C: Yes, you can use my mobile to make the video and upload it. It also tweets the link to the video, if you like. But you can also download it from the App store. Just look for Video Tweeter.

As a consequence, we need to consider the social context during the discovery process. This requires us to address to additional challenges: a lightweight coordination language which can be used in the social context and support for monitoring in order to keep track of the progress of Service compositions for coordination purposes.

your ikangai phd writing team

(c) 2012 Martin Treiber – All rights reserved.

Principles of Service Oriented Architectures (SOA) have been successfully applied for the solutions of business problems and related challenges regarding the integration of heterogeneous software systems in business processes. For this purpose, the so-called Big Web Services technology stack with standards like SOAP, WSDL, WS-Addressing or WS-Security was devised and supporting tools were implemented. These standards ensure that there is a level of common understanding between businesses partners and allow for platform independent communication between remote software Services and their composition/coordination with dedicated languages like BPEL or YAWL.

However, due to the perceived complexity of Big Web Services, Restful Web Services that build on well known W3C/IETF standards such as HTTP, XML or URI have been proposed as (lightweight) alternative. In particular, so-called Service Mashups were introduced, which provide solutions to very specific and narrow business integration problems. The ability of non experts to create Mashup applications is considered to increase the productivity of employees in their daily routine work and when working with different companies on joined projects.

In this context, a growing number of Services can be observed that represent real-world business activities which are performed by humans rather than Software. A prominent example is Amazon Mechanical Turk where tasks are distributed to human workers (Turkers) that offer all kind of Services. As a result, additional standards for requesting work of humans via standardized Service interfaces have been devised, including WS-Human Task and Human Provided Services (HPS). These standards allow for the seamless integration of humans into existing workflows and foster the collaboration in so called mixed Service environments of human and software Services.

The parallel rapid development of mobile technologies and their wide spread adoption, led to a situation, where many employees actually do their job while they are moving. Thus, mobile employees often perform Service work remotely at the location of the customer and their work require the availability of mobile handheld devices such as tablets and smartphones. While early mobile Services focused on simple tasks of entering the data in a dedicated handheld device, modern mobile workers often face complex tasks that require the coordination of several activities of different mobile employees.

Consequently, a lightweight approach for Service compositions is also attractive for mobile workers, because existing SOA standards are difficult to implement on mobile devices because of the volatile characteristics of mobile devices in terms of network connectivity and availability due to limitations in terms of power supply. These are the main reasons that past efforts of adopting SOA on mobile devices focused on the consumption of remote (Web) Services from mobile devices, whereas the provision and composition of Services on mobile devices did not receive as much support. Instead, Apps have emerged as primary means for Service provision on mobile devices. Apps are independent pieces of software that offer a well defined set of functionality are controlled by the user. On average, users install approximately between 14 and 40 Apps on their devices that cover a broad range of functionality: social networking, weather, sports, location information, dictionaries, photography and games are among the most common classes of Apps being used.

In our work, we study the applicability of SOA principles with regard to existing (mobile) infrastructures like App Stores and mobile Apps. Specifically, we analyze established SOA principles like Service provision, Service binding, Service discovery and Service composition in the context of mobile devices and investigate the mapping of SOA infrastructure to a mobile infrastructure. We also address the social aspect of mobile Service provision: mobile Services – being bound to a human – run on devices which are controlled by the owner who can decide if a Service is executed (provided) or not.

To address core mobility aspects like limitations of connectivity, we introduce a lightweight programming language called Tweetflows that provides communication mechanisms to invoke Apps remotely and consequently the means to compose Apps. In this regard, we study the application of microblogging services (e.g., Twitter) as communication backbone for the use of mobile Services in a social context.

your ikangai phd writing team

(c) 2012 Martin Treiber – All rights reserved.