Proprietary Implementations Research Articles

On Performance and Scalability of Cost-Effective SNMP Managers for Large-Scale Polling

As networks grow larger in size and complexity, their monitoring is becoming an increasing challenge because of the required polling performance and also due to heterogeneity of devices. As it turns out, SNMP (Simple Network Management Protocol) is by far the most popular monitoring protocol. However, due to the increase in the number of network devices, it becomes necessary to employ multiple SNMP managers, which is not cost-effective due to the hardware requirements. Additionally, the different proprietary SNMP implementations require custom configuration very often, as new devices are being incorporated into the network. Therefore, current SNMP managers not only require capabilities for large-scale monitoring but also a high degree of flexibility and programmability. In response, we propose an SNMP manager architecture with a flexible multi-threaded architecture, which effectively reduces the hardware resources necessary to poll the increasing number of SNMP agents. In addition, it features a scripting component to deal with the different data representations caused by proprietary implementations. Our experience has shown that SNMP agents can have high variability in their response times. Actually, our findings show a strong correlation between high response times and CPU load. As a solution, we propose and analyze novel adaptive polling algorithms that decrease the load on agents' CPUs while keeping the desired polling rate for fast agents. Finally, we present several real-world use cases where we show the benefits of the polling algorithms and the scripting component, by means of extensive measurement campaigns.

An Exhaustive Survey on P4 Programmable Data Plane Switches: Taxonomy, Applications, Challenges, and Future Trends

Traditionally, the data plane has been designed with fixed functions to forward packets using a small set of protocols. This closed-design paradigm has limited the capability of the switches to proprietary implementations which are hard-coded by vendors, inducing a lengthy, costly, and inflexible process. Recently, data plane programmability has attracted significant attention from both the research community and the industry, permitting operators and programmers in general to run customized packet processing functions. This open-design paradigm is paving the way for an unprecedented wave of innovation and experimentation by reducing the time of designing, testing, and adopting new protocols; enabling a customized, top-down approach to develop network applications; providing granular visibility of packet events defined by the programmer; reducing complexity and enhancing resource utilization of the programmable switches; and drastically improving the performance of applications that are offloaded to the data plane. Despite the impressive advantages of programmable data plane switches and their importance in modern networks, the literature has been missing a comprehensive survey. To this end, this paper provides a background encompassing an overview of the evolution of networks from legacy to programmable, describing the essentials of programmable switches, and summarizing their advantages over Software-defined Networking (SDN) and legacy devices. The paper then presents a unique, comprehensive taxonomy of applications developed with P4 language; surveying, classifying, and analyzing more than 200 articles; discussing challenges and considerations; and presenting future perspectives and open research issues.

Clinical decision support models and frameworks: Seeking to address research issues underlying implementation successes and failures

Computer-based clinical decision support (CDS) has been pursued for more than five decades. Despite notable accomplishments and successes, wide adoption and broad use of CDS in clinical practice has not been achieved. Many issues have been identified as being partially responsible for the relatively slow adoption and lack of impact, including deficiencies in leadership, recognition of purpose, understanding of human interaction and workflow implications of CDS, cognitive models of the role of CDS, and proprietary implementations with limited interoperability and sharing.To address limitations, many approaches have been proposed and evaluated, drawing on theoretical frameworks, as well as management, technical and other disciplines and experiences. It seems clear, because of the multiple perspectives involved, that no single model or framework is adequate to encompass these challenges. This Viewpoint paper seeks to review the various foci of CDS and to identify aspects in which theoretical models and frameworks for CDS have been explored or could be explored and where they might be expected to be most useful.

Semblance, coherence, and other discontinuity attributes

Discontinuity calculations, also called coherence or semblance, are some of the most commonly used seismic attributes. They measure the amount of similarity between adjacent seismic traces. However, there are several types of discontinuity estimates and a plethora of names for similar attributes. As a result, it can be difficult to understand the differences among them. Although the discontinuity algorithm that any particular software package uses might be unknown, most are based on one of a few published methods. Understanding published discontinuity attributes gives insight into the trade-offs among different proprietary implementations. Therefore, in this tutorial and the accompanying Jupyter notebook, we will explore simplified Python implementations of a few widely used discontinuity algorithms.

Comparison of Electronic Health Record System Functionalities to support the patient recruitment process in clinical trials

ObjectivesReusing data from electronic health records for clinical and translational research and especially for patient recruitment has been tackled in a broader manner since about a decade. Most projects found in the literature however focus on standalone systems and proprietary implementations at one particular institution often for only one singular trial and no generic evaluation of EHR systems for their applicability to support the patient recruitment process does yet exist. Thus we sought to assess whether the current generation of EHR systems in Germany provides modules/tools, which can readily be applied for IT-supported patient recruitment scenarios. MethodsWe first analysed the EHR portfolio implemented at German University Hospitals and then selected 5 sites with five different EHR implementations covering all major commercial systems applied in German University Hospitals. Further, major functionalities required for patient recruitment support have been defined and the five sample EHRs and their standard tools have been compared to the major functionalities. ResultsIn our analysis of the site's hospital information system environments (with four commercial EHR systems and one self-developed system) we found that – even though no dedicated module for patient recruitment has been provided – most EHR products comprise generic tools such as workflow engines, querying capabilities, report generators and direct SQL-based database access which can be applied as query modules, screening lists and notification components for patient recruitment support. A major limitation of all current EHR products however is that they provide no dedicated data structures and functionalities for implementing and maintaining a local trial registry. ConclusionsAt the five sites with standard EHR tools the typical functionalities of the patient recruitment process could be mostly implemented. However, no EHR component is yet directly dedicated to support research requirements such as patient recruitment. We recommend for future developments that EHR customers and vendors focus much more on the provision of dedicated patient recruitment modules.

On the Evaluation of the Complex-Valued Exponential Integral

Abstract Although its applications span a broad scope of scientific fields ranging from applied physics to computer graphics, the exponential integral is a nonelementary special function available in specialized software packages but not in standard libraries, consequently requiring custom implementations on most platforms. In this paper, we provide a concise and comprehensive description of how to evaluate the complex-valued exponential integral. We first introduce some theoretical background on the main characteristics of the function, and outline available third-party proprietary implementations. We then provide an analysis of the various known representations of the function and present an effective algorithm allowing the computation of results within a desired accuracy, together with the corresponding pseudocode in order to facilitate portability onto various systems. An application to the calculation of the closed-form solution to single light scattering in homogeneous participating media illustrate...

A review of interoperability and possibilities for data analysis from virtual world environments

Massively multi-user online virtual environments are gaining widespread attention and use. There are both proprietary and open-source implementations of these environments and they also use different communication protocols and data formats. After studying some of those protocols and formats, this paper provides a review of the current state of the art in the interoperability of these systems and elaborates on the possibilities of data analysis provided by them. A set of features regarding interoperability and data analysis is proposed, including the use of open communication protocols and content formats, then some of the most popular virtual world platforms (Second Life, OpenSim, Taiga, Active Worlds, Open Wonderland, Croquet Project, Tundra and Sirikata) are compared in terms of those features.

An Overview of IPTV Standards Development

In the last few years, IPTV has emerged as one of the major distribution and access techniques for broadband multimedia services. It is one of the primary growth areas for the telecommunications industry. However, existing IPTV systems are generally based on proprietary implementations that do not provide interoperability. Recently, many international standard bodies have published, or are developing, a series of IPTV related standards.. This paper is an overview of the most significant recent and upcoming IPTV standards.

Implementing interactive analysis of attack graphs using relational databases

An attack graph models the causal relationships between vulnerabilities. Attack graphs have important applications in protecting critical resources in networks against sophisticated multi-step intrusions. Currently, analyses of attack graphs largely depend on proprietary implementations of specialized algorithms. However, developing and implementing algorithms causes a delay to the availability of new analyses. The delay is usually unacceptable due to rapidly-changing needs in defending against network intrusions. An administrator may want to revise an analysis as soon as its outcome is observed. Such an interactive analysis, similar to that in decision support systems, is desirable but difficult with current approaches based on proprietary implementations of algorithms. This paper addresses the above issue through a relational approach. Specifically, we devise a relational model for representing necessary inputs, such as network configurations and domain knowledge, and we generate attack graphs from these inputs as relational views. We show that typical analyses can be supported through different type of searches in an attack graph, and these searches can be realized as relational queries. Our approach eliminates the needs for implementing algorithms, because an analysis is now simply a relational query. The interactive analysis of attack graphs becomes possible, since relational queries can be dynamically constructed and revised at run time. As a side effect, experimental results show that the mature optimization techniques in relational databases can transparently improve the performance of the analysis.

Mixed signals [Zigbee

We are now - if the vendors involved are to be believed - living in the age of ZigBee. Like Bluetooth, it mainly operates in the licence-exempt industrial, scientific and medical (ISM) band around 2.4GHz. Unlike Bluetooth, which is predominantly used for wireless headsets, it is intended for short range data communications between `intelligent' devices. This puts in firmly in the industrial and commercial sector, as opposed to Bluetooth which now sits almost exclusively in the consumer space. The focus on industrial and not consumer applications means ZigBee faces a difficult challenge; it needs to offer the performance demanded by industrial and commercial applications, but with a competitively low price tag when compared to existing proprietary implementations - both wired and wireless - in a highly fragmented marketplace.

Will binary XML speed network traffic?

XML has become integral to many critical enterprise technologies because of its ability to enable data interoperability between applications on different platforms. XML use is thus increasing rapidly. XML is so important that the industry is looking for ways to make its data load more manageable. XML currently uses only a plain-text format. The World Wide Web Consortium (W3C), which oversees and manages XML's development as a standard, and Sun Microsystems are working on binary XML formats. Some industry observers have expressed concern that multiple formats or proprietary implementations of binary XML could lead to incompatible versions, which would reduce the openness that makes the technology valuable. Because binary XML is suitable when network efficiency is important, users might decide to work with it only for high-volume applications that demand the best performance like financial transactions.

Contemplating some open challenges in SIP

Session Initiation Protocol (SIP), despite its beginnings as a protocol for multimedia session signaling over the Internet, has rapidly evolved as a prominent signaling protocol for Internet telephony. While most efforts to evolve the protocol have resulted in greater simplicity, flexibility, and extensibility, some uncoordinated efforts have engendered a few open challenges for the protocol implementers. In this paper, we contemplate some of these challenges, including the 3rd Generation Partnership Project's (3GPP's) use of SIP, flexibility in the service model, lack of ratification of user/application interaction model, and network address translator (NAT) traversal. In analyzing these issues, it is important to recognize two facts early. First, some of these issues are inherent in Internet telephony in general and are not endemic to SIP. Second, although standards bodies are attempting to address most of these issues, competing and proprietary implementations are emerging to the detriment of the entire SIP community.

An Economic Analysis of the Introduction of an Electronic Data Interchange System

Although electronic data interchange (EDI) holds the promise of significantly increasing the efficiency of business transactions, an installed base of proprietary implementations has been detrimental to the widespread acceptance of the technology. Thus, an important research issue involves strategies for facilitating EDI adoption. We analyze the introduction of an EDI system in a vertical market involving one manufacturer and two suppliers. The manufacturer initiates an EDI network, and penalizes a supplier for not joining the system by reducing its volume of business with the supplier. Along with a “stick,” the manufacturer can also use a “carrot” in the form of a subsidy to partially offset a supplier's setup cost. The competition between the suppliers is characterized by incentive types for joining the EDI system (“motivating” or “threatening”) and the Information Technology (IT) efficiency (“efficient” or “inefficient”). We show that regardless of its cost structure, a supplier may have to join the EDI network out of “strategic necessity,” due to the presence of an IT-efficient supplier. Our analysis further shows that depending on the supplier competition structure, the EDI system may prove to be a “beneficial” strategic necessity for a large supplier and an “unfortunate” strategic necessity for a small supplier. Another key result is that by increasing the severity of the penalty, both the manufacturer and the follower supplier can be worse off under certain conditions. The analysis of subsidy strategies reveals that unless leadership and followership positions are reversed due to a subsidy, subsidizing a supplier has no impact on the joining time of its competitor. Thus the EDI initiator cannot induce both suppliers to join earlier by subsidizing one supplier. Also, the larger the slack capacity of the leader, the higher (lower) the manufacturer's incentive to subsidize the leader (follower). These results offer insights for initiators and adopters regarding penalty and subsidy strategies, impact on competition structure, joining decisions and network growth.