Coordinating Asynchronous Actors – from Tuple Spaces to Tweetflows

The coordination of asynchronous actors has always been a major problem in distributed systems and parallel computing. About 20 years ago, David Gelernter and Nicholas Carriero have introduced the coordination language Linda. The most important difference to existing approaches was that they treated the coordination problem seperately from the computation problem. Linda implementations offer the [...]

Q and A – ? and ! – Questions and Answers in Tweetflows. How “!” and “?” can be used for Service publication and Service requests.

Tweetflow Natural Language Generation

Hi, My Praktikums-Topic is about creating an Android client for generating natural sentences out of Tweetflows. As you might have read already, Tweetflows are used to create mobile workflows. Tweetflows should be useable by humans, but actually they have a quite technical syntax. If you are not familiar with it and may have not a [...]

Local Twitter registry to parse and register Tweetflows

Hey there, here is my first blog entry for a new practical course at the Distributed Systems Group. My project is about Twitter, with the main purpose to find an intelligent way to realize an artificial word-to-mouth propaganda with Tweetflows on Twitter. To illustrate the idea, let us assume that I am searching for someone [...]

Migration of .net Workflows between different hosts

As part of my master thesis on “cloud-based adaptations of service composition hostings” the .net WCF class WorkflowPersistenceService prooved as a promising tool for workflow migrations. class AdaptationPersistenceService: WorkflowPersistenceService { WorkflowAdaptationProxy wap = new WorkflowAdaptationProxy(); protected override void SaveWorkflowInstanceState(Activity rootActivity, bool unlock) { Guid instanceId = (System.Guid)rootActivity.GetValue(Activity.ActivityContextGuidProperty); Console.WriteLine(“Saving Instance {0} “, instanceId); byte[] rootBytes = [...]

Web Services Security

To make our Web services secure, we have to to know the associated threats. The top threats directed at Web services are: Unauthorized access Parameter manipulation Network eavesdropping Disclosure of configuration data Message replay To avoid attack or abuse of  vulnerabilities we can consider the following Standards in our implementation: XML Encryption (W3C): Message level [...]

Lightweight Service Invocation using Twitter

Lightweight Service Invocation over Twitter can provide benefits through reuse of existing social structures and crowdsourcing opportunities. This article describes an example scenario and the corresponding tweetflow primitives that could be used to control publication, binding, search, invocation, coordination and monitoring of computer-provided as well as human-provided services.

Twitter Communication Primitives

Using Twitter for project communication –

Using URL schemata to bind and invoke Services on mobile devices – Introduction

Using URL schemata to bind and invoke Services on mobile devices – ikangai’s first public paper.

Writing Scientific Papers

Successful ICSE 2011 paper submission of ikangai :-) . Our Apps q·.:Launcher and q·.:Card are now part of a scientific paper :-) .