Abstract:
The growing synergy between Web Services and Grid or cloud based technologies is enabling profound, dynamic interactions between applications dispersed in geographic, institutional, and conceptual space. Such deep interoperability requires the simplicity, robustness, and extensibility for which XML has been conceived, making it a natural lingua franca for the network. Along with these advantages, there is a degree of inefficiency that may limit the applicability of XML.
In this paper, we investigate the limitations of XML for high-performance and high-interactive distributed computing. Our experimental results clearly show that focusing on parsers, that are routinely used for desterilize XML messages exchanged in these system, we can improve the performance of a generic the end to end web services based solution. Then we present a new parser, the Cache Parser, which uses a cache to reduce the parsing time by reusing information related to previously parsed documents/messages similar to the one under examination. Finally, we will show how our fast parser can improve the global throughput of any application based on Web or Grid or Cloud Services, or also RPC calls in general.

Key words: Web Service, Cloud Services, 3 tier architecture, SOA, RPC, Service Oriented Architecture

The may Web Services fully solve the “global enterprise integration” problem, but the proposed solution seems to exhibit a poor performance, and we believe that this could pose serious limitations on their actual applicability, as the number of commercial users will increase.
As shown in paragraph 2 we also believe that one of the limitations in using a full WS approach for implementing complex and highly interactive systems, comes from the large de-marshalling costs incurred on the receiver sides.
To solve this problem, we have designed a new parser: the Cache Parser. It is able to “well and quickly” retrieve information from XML documents, using previous knowledge about the document syntactic tree. In particular, our Cache Parser, which is used to de-marshal XML messages on the receiver side:

• Uses a checksum to detect if a new document is “well formatted”, and to know if it shares the syntactic tree with an already parsed one.
• Takes advantage of this XML-Document syntactic tree stored in a cache.
• It is based on a strict collaboration between sender and receiver.
• Consistently reduces the receiver parse time, without increasing the sender document creation time.

This algorithm is 25 time faster than a pull parser and if used in a WS scenario it can allow a 1.54 performance improvement factor in term of request handled per second. Finally it can be applied in any scenario where the client and the server decide to cooperate.

Full article available at this link.

Your help in sharing the idea is very welcome!

Improving the #performance of XML based technologies by caching and reusing #Information. #Webseries #RealTime #CloudComputing #API #APIs #programming #softwareengineering
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Cite this paper as:

F. Lelli, G. Maron, and S. Orlando. Improving the Performance of XML Based Technologies by Caching and Reusing Information.. IEEE International Conference on Web Services (ICWS), Chicago, September 2006.

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• A web server‘s fundamental job is to accept and fulfill requests from clients for static content from a website (HTML pages, files, images, video, and so on). The client is almost always a browser or a mobile application, and the request takes the form of a Hypertext Transfer Protocol (HTTP) message, as does the web server’s response.
• An application server’s fundamental job is to provide its clients with access to what is commonly called business logic, which generates dynamic content. That is, it’s code that transforms data to provide the specialized functionality offered by a business, service, or application.

These servers are typically physically part of an Intranet, an Extranet, or the Internet:

• An intranet is a computer network for sharing information, collaboration tools, operational systems, and other computing services within an organization, usually to the exclusion of access by outsiders.
• An extranet is a controlled private network that allows access to partners, vendors, and suppliers or an authorized set of customers – normally to a subset of the information accessible from an organization’s intranet.
• The Internet is a global computer network providing a variety of information and communication facilities, consisting of interconnected networks using standardized communication protocols.

The #Web is a collection of #servers located in #internet extranet and intranet. Here you can find an introduction to computer networks:
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The video below provides an introduction to how software and hardware are organized in order to ensure proper interoperability. Note that it is featuring Netscape as the browser of choice: the video is old but still relevant.

I believe that the video above is a good introduction to Computer Networks. Some of the components mentioned include:

• LAN (Local Area Network): A local area network is a computer network that interconnects computers within a limited area such as a residence, school, laboratory, university campus, or office building. LAN are a collection of cables and switches. WiFi is a particular type of LAN.
• Packets (IP, Data, etc): A network packet is a formatted unit of data carried by a packet-switched network. A packet consists of control information and user data; the latter is also known as the payload. Control information provides data for delivering the payload.
• Router (local or remote): Performs the traffic directing functions on the Internet. Data sent through the internet, such as a web page or email, is in the form of data packets. A packet is typically forwarded from one router to another router through the networks that constitute an internetwork (e.g. the Internet) until it reaches its destination node. The video also mentions Router-switch, that normally are routers of better quality that sit at the intersection of your LAN and the internet.
• Proxy Server: A server application or appliance that acts as an intermediary for requests from clients seeking resources from servers. It may also offer security features as well as filtering capabilities.
• URL: A Uniform Resource Locator, colloquially termed a web address, is a reference to a web resource that specifies its location on a computer network and a mechanism for retrieving it.
• Firewall: A system designed to prevent unauthorized access to or from a private network. You can implement a firewall in either hardware or software form, or in a combination of both. Firewalls prevent unauthorized internet users from accessing private networks connected to the internet, especially intranets and extranets. Firewalls have ports (or doors) that are open for communication and other that are closed. The most common ports are 80 for standard internet traffic and 25 for e-mail traffic.
• IP, TCP/IP, UDP/IP: They are a part of the Internet protocol suite. It is a conceptual model that defines the communications protocols used in the Internet and similar computer networks. It is commonly referred to as TCP/IP because the foundational protocols in the suite are the Transmission Control Protocol and the Internet Protocol.

From the picture below you can get an idea on how these servers are organized.

Introduction to Network of #computers and #HowTo Internet Works.
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The video linked above also mentions a particular form of attack known as “ping of death” that involves sending a malformed or otherwise malicious ping to a computer. This is possible because the Internet is an uncontrolled area where not all the participants may decide to play in a fair manner. Another common attack is the “DNS attack”, an exploit in which an attacker takes advantage of vulnerabilities in the domain name system (DNS).

This article (Introduction to Computer Networks and How Internet Works) is part of a minicollection of tutorials on the building block of a software architecture.

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Current cloud service description languages envision the ability to automatically combine cloud service offerings across multiple abstraction layers, i.e. software, platform, and infrastructure service offerings, to achieve a common shared business goal. However, only little effort has
been spent in this direction. This paper formalizes the issue of automatic combination of cloud services showing its computationally intensive nature. In order to overcome this issue we propose a Resource Description Framework (RDF)- based prototype implementation that leverages a batch process for automatically constructing possible combinations of cloud services. Using this approach we are able to analyze possible combinations of cloud services that may fit particular customer needs in a timely fashion

Some relevant Key words: Cloud, Cloud Services, Service, Composition, RDF for Cloud

Cloud resources offered as services can be described using a common schema model and hence can be composed in order to achieve a common business goal. We present in this paper the issue of composing cross-layered cloud services to build a Service-based Cloud Application (SBCA), and formalize it as a tree navigation algorithm involving external approaches for matching cloud service descriptions.
Given the fact that there could be a huge number of cloud service offerings in a real marketplace, this algorithm may grow exponentially and become a computationally intensive task. For our prototype implementation, RDF is used to create a sample model containing sample cloud service offerings, a batch process is implemented to continuously scan the model and discover possible compositions of cloud services, and SPARQL is used to retrieve cloud services and their possible compositions in a timely fashion. In the future, we intend to continue investigating the issue of cross-layered cloud service composition in order to discover and quantify the benefits and the limits of this approach by providing experimental results.

Full article available at the following link:

Issue in Automatic Combination of Cloud Services:
https://doi.org/10.1109/ISPA.2012.71

Your help in sharing the idea is very welcome!

Cite this paper as:

D. K. Nguyen and F. Lelli, Issue in Automatic Combination of SaaS, PaaS and IaaS, 10th International Symposium on Parallel and Distributed Processing with Application ISPA 2012 track Clouds for Business and Business for Clouds, Spain, Madrid, July 2012

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• The Many Faces of the Integration of Instruments and the Grid

#issues in #automatic Combination of #Cloud #services for #CloudComputing #RDF and understanding meta-information
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In the past few years, the idea of extending the Grid to cover also the remote access, control, management of instrument devices has been explored in a few initiatives. Existing tools lack in generality and require advanced specialized computer science knowledge, thus making them difficult to be broadly adopted in the scientific community. In this paper we present a new open source initiative that is designed to overcome these problems. The Tiny Instrument Element project defines a high level architecture for plugging instruments into the Grid and provides the corresponding skeleton implementation. This lightweight approach, as opposed to existing middleware-based solutions, reduces the effort required to Gridify existing instruments. The paper evaluates the proposed abstraction with a case study from a pervasive computing scenario.

Some relevant Key words: IoT, Internet of things, smart devices, cloud computing, web service, ubiquitous computing, plugin.

In this paper we present the Tiny Instrument Element project showing our proposed novel approach to the integration between instruments and the Grid. Instead of building a new middleware we propose to use a semifinite artifact (i.e., a skeleton software) that can be tailored to meet the requirements of a specific instrument characteristics. This approach not only provides an uniform access to the Gridified instruments but also leaves the flexibility to customize and tune the Tiny Instrument Element for optimal monitoring and control of the instruments. From the case study we have seen that none of the code included in the Tiny Instrument Element release was redundant and that the time required in order to gain a good understanding of the API and the corresponding skeleton was quite small. This supports the idea of template-based software development. The Project has started full open source activities in September 2008. If we exclude our personal activity and the one performed by the case study participants, until the end of 2008, the project website attracted 304 unique visitors (7 Returning many times). The source code was downloaded 40 times and the authors were contacted with positive feedback by 2 users of the community. Whereas the project has been running for a relatively short time, these numbers are promising and show the benefit of a transparent development process to achieve wider dissemination of our research ideas

Full article available at the following link:

The Tiny Instrument Element:
https://doi.org/10.1007/978-3-642-01671-4_27

Read the paper at this link

Your help in sharing the idea is very welcome!

Cite this paper as:

F. Lelli and C. Pautasso The Tiny Instrument Element Project In proc of 4th International Conference on Grid and Pervasive Computing (GPC) , Geneva, Switzerland, May 2009

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• The Many Faces of the Integration of Instruments and the Grid

The #tiny Instrument Element for integrating #IoT and #Cloud . An early precursor of #EdgeComputing
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