| 1. |
- Berglund, Åsa, et al.
(författare)
-
Towards goal-based autonomic networking
- 2009. - 1
-
Ingår i: Proceedings of the Distributed Autonomous Network Magagement Systems Workshop (DANMS 2008), November 2008.
-
Konferensbidrag (refereegranskat)abstract
- The ability to quickly deploy and efficiently manage services is critical to the telecommunications industry. Currently, services are designed and managed by different teams with expertise over a wide range of concerns, from high-level business to low level network aspects. Not only is this approach expensive in terms of time and resources, but it also has problems to scale up to new outsourcing and/or multi-vendor models, where subsystems and teams belong to different organizations. We endorse the idea, upheld among others in the autonomic computing community, that the network and system components involved in the provision of a service must be crafted to facilitate their management. Furthermore, they should help bridge the gap between network and business concerns. In this paper, we sketch an approach based on early work on the hierarchical organization of autonomic entities that possibly belong to different organizations. An autonomic entity governs over other autonomic entities by defining their goals. Thus, it is up to each autonomic entity to decide its line of actions in order to fulfill its goals, and the governing entity needs not know about the internals of its subordinates. We illustrate the approach with a simple but still rich example of a telecom service.
|
|
| 2. |
|
|
| 3. |
- Boström, Gustav, et al.
(författare)
-
Quality of Service Evaluation in Virtual Organizations Using SLAs
- 2006. - 1
-
Ingår i: 1st International Workshop on Interoperability Solutions to Trust, Security, Policies and QoS for Enhanced Enterprise Systems (IS-TSPQ 2006).
-
Konferensbidrag (refereegranskat)abstract
- Cooperating in Virtual organizations requires trust between the constituting organizations. SLA contracts are put in place in order to specify the quality of service of services offered. For these contracts to be effective they also need to be monitored effectively. In a Service Oriented Architecture this often means monitoring Web service invocations and evaluating if the service fulfills the obligations in its SLA. In this paper we present an implementation of a rule engine based SLA Evaluator specifically designed for the needs of a virtual organization. The evaluator fits in the context of a virtual organization through the use of open XML-based standards and a loosely coupled, event-driven architecture.
|
|
| 4. |
|
|
| 5. |
- Darko-Ampem, Sakyibea, et al.
(författare)
-
Secure negotiation in virtual organizations
- 2006
-
Ingår i: Proceedings - 2006 10th IEEE International Enterprise Distributed Object Computing Conference Workshops. - 076952558X - 9780769525587
-
Konferensbidrag (refereegranskat)abstract
- Virtual organizations are dynamic associations of business partners that join forces to achieve a common goal. Because partners live in very competitive environments and they do not fully trust each other, they establish contractual agreements to help reduce the risk of participating in the virtual organization. This naturally puts severe demands on the security of the process leading to the establishment of a contract, including negotiation of terms and conditions. The open context in which virtual organizations are created raises further security concerns. This papers discusses the security requirements over contract negotiation that arise in this context, examines current negotiation protocols and proposes enhancements to one of them.
|
|
| 6. |
- Giambiagi, Pablo, et al.
(författare)
-
Language-Based Support for Service Oriented Architectures: Future Directions
- 2006. - 1
-
Ingår i: 1st International Conference on Software and Data Technologies (ICSOFT 2006).
-
Konferensbidrag (refereegranskat)abstract
- The fast evolution of the Internet has popularized service-oriented architectures (SOA) with their promise of dynamic IT-supported inter-business collaborations. Yet this popularity does not reflect on the number of actual applications using the architecture. Programming models in use today make a poor match for the distributed, loosely-coupled, document-based nature of SOA. The gap is actually increasing. For example, interoperability between different organizations, requires contracts to reduce risks. Thus, high-level models of contracts are making their way into service-oriented architectures, but application developers are still left to their own devices when it comes to writing code that will comply with a contract. This paper surveys existing and future directions regarding language-based solutions to the above problem.
|
|
| 7. |
- Giambiagi, Pablo, et al.
(författare)
-
Memory Consumption Analysis of Java Smart Cards
- 2005. - 1
-
Konferensbidrag (refereegranskat)abstract
- Memory is a scarce resource in Java smart cards. Developers and card suppliers alike would want to make sure, at compile- or load-time, that a Java Card applet will not overflow memory when performing dynamic class instantiations. Although there are good solutions to the general problem, the challenge is still out to produce a static analyser that is certified and could execute on-card. We provide a constraint-based algorithm which determines potential loops and (mutually) recursive methods. The algorithm operates on the bytecode of an applet and is written as a set of rules associating one or more constraints to each bytecode instruction. The rules are designed so that a certified analyser could be extracted from their proof of correctness. By keeping a clear separation between the rules dealing with the inter- and intra-procedural aspects of the analysis we are able to reduce the space-complexity of a previous algorithm.
|
|
| 8. |
- Giambiagi, Pablo, et al.
(författare)
-
On the expressiveness of CCS-like calculi
- 2004
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- In the literature there are several CCS-like process calculi, or CCS variants, differing in the constructs for the specification of infinite behavior and in the scoping rules w.r.t. channel names. In this paper we study various representatives of these calculi based upon both their relative expressiveness and the decidability of divergence (i.e., the existence of a divergent computation). We regard any two calculi as being equally expressive iff for every process in each calculus, there exists a weakly bisimilar process in the other.By providing weak bisimilarity preserving mappings among the various variants, we show that in the context of relabeling-free and finite summation calculi: (1) CCS with parameterless (or constant) definitions is equally expressive to the variant with parametric definitions. (2) The CCS variant with replication is equally expressive to that with recursive expressions and static scope. We also state that the divergence problem is undecidable for the calculi in (1) but decidable for those in (2). We obtain this from previous (un)decidability results and by showing the relevant mappings to be computable and to preserve divergence and its negation. From (1) and the well-known fact that parametric definitions can replace injective relabelings, we show that injective relabelings are redundant (i.e., derived) in CCS (which has constant definitions only).
|
|
| 9. |
- Giambiagi, Pablo, et al.
(författare)
-
On the expressiveness of infinite behavior and name scoping in process calculi
- 2004. - 1
-
Ingår i: Foundations of Software Science and Computation Structures (7th Intl Conference, FOSSACS 2004, Held as Part of the Joint European Conferences on Theory and Practice of Software, ETAPS 2004, Barcelona, Spain, March 29 – April 2, 2004. Proceeding). - Berlin, Heidelberg : Springer. - 9783540212980 ; , s. 226-240
-
Bokkapitel (refereegranskat)abstract
- In the literature there are several CCS-like process calculi differing in the constructs for the specification of infinite behavior and in the scoping rules for channel names. In this paper we study various representatives of these calculi based upon both their relative expressiveness and the decidability of divergence. We regard any two calculi as being equally expressive if for every process in each calculus, there exists a weakly bisimilar process in the other. By providing weak bisimilarity preserving mappings among the various variants, we show that in the context of relabeling-free and finite summation calculi: (1) CCS with parameterless (or constant) definitions is equally expressive to the variant with parametric definitions. (2) The CCS variant with replication is equally expressive to that with recursive expressions and static scoping. We also state that the divergence problem is undecidable for the calculi in (1) but decidable for those in (2). We obtain this from (un)decidability results by Busi, Gabbrielli and Zavattaro, and by showing the relevant mappings to be computable and to preserve divergence and its negation. From (1) and the well-known fact that parametric definitions can replace injective relabelings, we show that injective relabelings are redundant (i.e., derived) in CCS (which has constant definitions only).
|
|
| 10. |
|
|
