S.Maffeis; "A Flexible System Design to Support Object Groups and ObjectOriented Distributed Programming"; in Proceedings of ECOOP'93, Lecture Notes in Computer Science 791, 1994.  Home/Search   Document Details and Download   Summary   Related Articles   Check

....focuses on online replacement of components, most related work implements faulttolerant behavior based on redundant execution and fault masking. The integration of fault tolerance techniques with real time computing is currently not under consideration in the OMG standardization process. Electra [Maffeis94]is a CORBA ORB implementation for reliable, distributed services. Electra extends the CORBA specification and provides group communication Integration of CORBA Services 4 mechanisms, reliable multicasts, and ....

S.Maffeis; "A Flexible System Design to Support Object Groups and ObjectOriented Distributed Programming"; in Proceedings of ECOOP'93, Lecture Notes in Computer Science 791, 1994.

....years. With the request for proposal for a Fault tolerant CORBA Using Entity Redundancy [OMG98a] issued in April 1998, OMG is seeking to incorporate existing approaches for software fault tolerance into future versions of CORBA. However, most related work, i.e. Morgan99] Felber98] Chang97] [Maffeis94], implements fault tolerant behavior based on redundant execution and fault masking without taking real time constraints into account, a property absolutely needed for ensuring the safety of the devices in a tele laboratory. While the OMG has founded a Real time CORBA special interest group (SIG) ....

S.Maffeis; "A Flexible System Design to Support Object Groups and Object-Oriented Distributed Programming"; in Proceedings of ECOOP'93, Lecture Notes in Computer Science 791, 1994.

....for software fault tolerance into future versions of CORBA. However, in contrast to our approach, which focuses on automatic generation and replication of replicated components, most related work implements fault tolerant behavior by extending the underlying CORBA object request broker. Electra [2] is a CORBA ORB implementation for reliable, distributed services. Electra extends the CORBA specification and provides group communication mechanisms, reliable multicasts, and object replication. The Electra ORB uses services from the underlying ISIS [3] and HORUS [4] systems. ORBIX ISIS is an ....

S.Maffeis; "A Flexible System Design to Support Object Groups and Object-Oriented Distributed Programming"; in Proceedings of ECOOP'93, Lecture Notes in Computer Science 791, 1994.

....3D gadgets will be applyed to enhance the existing interaction techniques. Finally, to benefit from object oriented design and programming paradigms, we plan the integration of other object oriented components into the ViRXIS architecture. One of these new components will be the ELECTRA toolkit [7], an object oriented distributed programming environment based on the CORBA standard [8] that may ease the communication between ViRXIS InterActor and ViRXIS ooDBMS and allow the handling of virtual environment objects on a high level base. 9. ....

Maffeis S., "A Flexible System Design to Support Object-Groups and ObjectOriented Distributed Programming", in: Guerraoui R., Nierstrasz O., Riveill M. (ed.), Proceedings of the ECOOP93 Workshop on Object-Based Distributed Programming, Lecture Notes in Computer Science 791, Springer, 1994.

....design, many platforms that support programming with distributed objects have been developed in recent years. A common approach to achieve separation of concerns is to use inheritance: objects inherit adequate behaviors from a set of predefined classes. Arjuna [19] Avalon [8] and Electra [20] are examples of such systems. Another approach bases the separation of concerns on reflective facilities that rely on two object levels: a base level and a meta level . Muse [34] Open C [6] and of course GARF are such systems. In GARF, the base level and the meta level correspond to the ....

....by the predefined behavioral objects associated through the garfNew: method. In that sense, Arjuna does not achieve separation of concerns as GARF does it. 7. 2 Electra Electra as well is an extension of the C programming language that offers support for the development of fault tolerant objects [20]. It is based on the Horus toolkit, which relies on the Multicast Transport Service (Muts) 28] Electra provides very similar abstractions for building fault tolerant objects to those supported by GARF. Those abstractions are implemented on top 20 Two different lightweight process schedulers ....

S. Maffeis. A Flexible System Design to Support Object-Groups and Object-Oriented Distributed Programming. In R. Guerraoui, O. Nierstrasz, and M. Riveill, editors, Object-Based Distributed Programming. Springer Verlag, 1994.

.... To take the advantages of the current distributed systems research and the technological stability achieved in fields like: group communication and process group abstractions [1] reliable groupcommunication protocols [2] group oriented systems [3] and object group programming paradigms [4], several contributions are trying to build and validate general purpose platforms integrating and lying on those group concepts and abstractions. Several authors have stressed the need to offer integrated frameworks providing facilities to use the potential of those concepts in distributed ....

....For asynchronous sessions, the collaborative session information is supported in the DSCS. Each participant will mainly interact only with it preferred (or available) server. This interaction is implemented by means of traditional remote object invocations using a remote method calling as in [4][41] with a very simple model represented in the figure 2. The Applicational Support Level can be understood as a collection of classes composing a general purpose object library implementing several common building blocks that can be used by different synchronous applications. This library ....

Maffeis, S., "A Flexible System Design to Support Object-Groups and Object-Oriented Distributed Programming", ECOOP'93 Workshop on Object-Based Distributed Programming, Lecture Notes in Computer Science 791, Springer Verlag (1994).

.... To take advantage of the current distributed systems research and the technological stability achieved in fields like: group communication and process group abstractions [1] reliable group communication protocols, group oriented systems or toolkits [2] and object group programming paradigms [3], several contributions are trying to build and validate general purpose platforms integrating and lying on those group concepts and abstractions. Several authors have stressed the need to offer integrated frameworks providing facilities to use the potential of those concepts in distributed ....

Maffeis, S., "A Flexible System Design to Support Object-Groups and Object-Oriented Distributed Programming", ECOOP'93 Workshop on Object-Based Distributed Programming, Lecture Notes in Computer Science 791, Springer Verlag, 1994.

....and can thus be passed from one node to another. Furthermore, objects are not tied to a client or server role; a client acting as server at a certain moment can be2 come a client at a later point and vice versa. Electra enhances OMA in that objects can be aggregated to so called object groups [11]. An objectgroup is a means of combining network objects and naming them as a unit (Figure 1) Communication is by reliable multicast , which means that a CORBA operation issued through a group reference is received by all implementations which are members of the group. Figure 1: Electra objects ....

....API provided by the underlying toolkit, a toolkit dependent Adaptor Object is implemented. An Adaptor Object cleanly encapsulates all of the program code which is specific to a toolkit and necessary to support the multicast RPC module. We call this system design principle the Adaptor Model [11]. To port Electra to a new toolkit, programmers only have to develop an appropriate Adaptor Object. Our adaptors for Horus, Isis, and MUTS comprise less than 1000 lines of C code each. Electra applications can be reconfigured to run on another toolkit by simply relinking them with the ....

Maffeis, S. A Flexible System Design to Support Object-Groups and Object-Oriented Distributed Programming. In Proceedings of the ECOOP '93 Workshop on Object-Based Distributed Programming (1994), Lecture Notes in Computer Science 791, Springer-Verlag.

....their own API, and (e) to devise a flexible design which other people can apply to their own systems. This section focusses on the design of the GTS server, which is implemented in the C programming language. A GTS server is structured in a way similar to the x kernel [13] and to Electra [11]. Each GTS server consists of a collection of adaptor objects plugged together to form a protocol tree as depicted in Figure 2. The root object (GTSroot) communicates with the client applications running in its cluster. Leaf Actor Crypt Compress Checksum Encode UUCP EMail TCP IPmulticast . ....

Maffeis, S. A Flexible System Design to Support Object-Groups and Object-Oriented Distributed Programming. In Proceedings of the ECOOP '93 Workshop on Object-Based Distributed Programming (1994), R. Guerraoui, O. Nierstrasz, M. Riveill, Ed., Lecture Notes in Computer Science 791, SpringerVerlag.

....Adaptor Object maps the Virtual Machine interface onto the proprietary API provided by the underlying toolkit. An Adaptor Object encapsulates all of the code which is specific to a toolkit and necessary to support the multicast RPC module. We call this system design principle the Adaptor Model [9]. To port Electra to a new toolkit, programmers only have to develop an appropriate Adaptor Object. Our adaptors for Horus, Isis, and MUTS comprise less than 1000 lines of C code each. Electra applications can be reconfigured to run on another toolkit by simply relinking them with the ....

Maffeis, S. A Flexible System Design to Support Object-Groups and Object-Oriented Distributed Programming. In Proceedings of the ECOOP '93 Workshop on Object-Based Distributed Programming (1994), Lecture Notes in Computer Science 791, Springer-Verlag.

....recipients as soon as they become available and register with GTS again. Addressing is by Uniform Resource Locators similar to the World Wide Web. 1. 2 Related Work Examples of state of the art toolkits offering process groups and reliable, order preserving multicast are Consul [12] Electra [10], Horus [14] Isis [4] and Transis [1] These toolkits primarily aim to support applications running within one LAN. If a process has been unresponsive for a certain (usually short) period of time, their default behavior is to regard the process as faulty and to exclude it from the system. If a ....

Maffeis, S. A Flexible System Design to Support Object-Groups and Object-Oriented Distributed Programming. In Proceedings of the ECOOP '93 Workshop on Object-Based Distributed Programming (1994), R. Guerraoui, O. Nierstrasz, M. Riveill, Ed., Lecture Notes in Computer Science 791, Springer-Verlag.

Online articles have much greater impact   More about CiteSeer.IST   Add search form to your site   Submit documents   Feedback  

CiteSeer.IST - Copyright Penn State and NEC