Alessio Botta | Università degli Studi di Napoli "Federico II" (original) (raw)

Papers by Alessio Botta

In this paper we present our traffic generation platform, named D-ITG (Distributed Internet Traff... more In this paper we present our traffic generation platform, named D-ITG (Distributed Internet Traffic Generator). Its features are first described. We believe that some capabilities are in fact innovative, since no other traffic generator offers them. Then, we describe the original architecture of D-ITG, which allows our traffic generator to achieve high performance. We hint at a comparison with other traffic generators and conclude with the ongoing work to add new features.

In this Technical Report we report our activities on the Design, Implementation, and Testing of a... more In this Technical Report we report our activities on the Design, Implementation, and Testing of a Hybrid Tool for Network Topology Discovery we called Hynetd.

Computer Networks, 2013

Nowadays, Cloud Computing is widely used to deliver services over the Internet for both technical... more Nowadays, Cloud Computing is widely used to deliver services over the Internet for both technical and economical reasons. The number of Cloud-based services has increased rapidly and strongly in the last years, and so is increased the complexity of the infrastructures behind these services. To properly operate and manage such complex infrastructures effective and efficient monitoring is constantly needed.

IEEE GLOBECOM 2008 - 2008 IEEE Global Telecommunications Conference, 2008

Networked embedded systems are gaining more and more attention and their use in current network s... more Networked embedded systems are gaining more and more attention and their use in current network scenarios is of indisputable importance. Research community and industry are proposing novel embedded solutions, often based on network processors, for network connectivity, data processing and service delivery. Despite this, quantitative performance comparisons of such systems seem to be very hard to find. In this paper, we describe an experimental analysis of different boards for networked embedded systems using both general-purpose and network processors, and running both commercial and open source operating systems. The results show that network-processor based boards are able to attain very high performance when compared to boards based on x86 processors, especially when running commercial operating systems. The analysis provides a reference for the design, development, and testing of novel networked embedded systems.

2014 International Conference on Future Internet of Things and Cloud, 2014

2012 Eighth International Conference on Signal Image Technology and Internet Based Systems, 2012

Understanding the ever-changing scenario of computer networks and how they operate in the real wo... more Understanding the ever-changing scenario of computer networks and how they operate in the real world implies measuring and analyzing their characteristics. This in turn requires a set of advanced tools and methodologies to be shared among researches, along with the data derived from such activities. In this paper we first present some of the main issues and challenges in the field of Internet Monitoring and Measurement, then we present several open source platforms we have developed in the last 10 years for monitoring heterogeneous and large scale networks. Finally, we describe some of the data sets we made publicly available to the research community.

In this Technical Report we report our activities on the Design, Implementation, and Testing of a... more In this Technical Report we report our activities on the Design, Implementation, and Testing of a Hybrid Tool for Network Topology Discovery we called Hynetd.

Future Generation Computer Systems, 2015

Even if Internet traffic analysis and characterization is a fer- tile research area, a lot of wor... more Even if Internet traffic analysis and characterization is a fer- tile research area, a lot of work still must be done to study and understand the traffic characteristics of new emerg- ing multimedia applications. Among them, an interesting category is that of multiplayer network games. This pa- per aims at demonstrating that, at packet level, spatial and temporal invariants exist

Computer Networks, Jan 1, 2009

In this paper we present our traffic generation platform, named D-ITG (Distributed Internet Traff... more In this paper we present our traffic generation platform, named D-ITG (Distributed Internet Traffic Generator). Its features are first described. We believe that some capabilities are in fact innovative, since no other traffic generator offers them. Then, we describe the original architecture of D-ITG, which allows our traffic generator to achieve high performance. We hint at a comparison with other traffic generators and conclude with the ongoing work to add new features.

Software Defined Networking (SDN) is an emerging paradigm that is expected to revolutionize compu... more Software Defined Networking (SDN) is an emerging paradigm that is expected to revolutionize computer networks.
With the decoupling of data and control plane and the introduction of open communication interfaces between layers, SDN enables programmability over the entire network, promising rapid innovation in this area.
The SDN concept was already proven to work successfully in cloud and data center environments thus the proper monitoring of such networks is already in the focus of the research community.
Methods for measuring Quality of Service (QoS) parameters such as bandwidth utilization, packet loss, and delay have been recently introduced in literature, but they lack a solution for tackling down the question of \emph{available bandwidth}.
In this paper, we attempt to fill this gap and introduce a novel mechanism for measuring available bandwidth in SDN networks.
We take advantage of the SDN architecture and build an application over the Network Operating System (NOS).
Our application can track the topology of the network and the bandwidth utilization over the network links, and thus it is able to calculate the available bandwidth between any two points in the network.
We validate our method using the popular Mininet network emulation environment and the widely used NOS called Floodlight.
We present results providing insights into the measurement accuracy and showing its relationship with the delay in the control network and the polling frequency.

In the field of network monitoring and measurement, the efficiency and accuracy of the adopted to... more In the field of network monitoring and measurement, the efficiency and accuracy of the adopted tools is strongly dependent on (i) structural and dynamic characteristics of the network scenario under measure and (ii) on manual fine tuning of the involved parameters. This is, for example, the case of the endto-end available bandwidth estimation, in which the constraints of the measurement stage vary according to the use of the final results. In this work we present UANM (Unified Architecture for Network Measurement), a novel measurement infrastructure for an automatic management of measurement stages, tailored to the end-to-end available bandwidth estimation tools. We describe in details its architecture, illustrating the features we introduced to mitigate the problems affecting available bandwidth estimation in heterogeneous scenarios. Moreover, to provide evidences of UANM benefits, we present an experimental validation in three selected scenarios deployed over a real network testbed: (i) we show how UANM is able to alleviate the interferences among concurrent measures; (ii) we quantify the overhead introduced by the use of UANM; (iii) we illustrate how UANM is capable to provide more accurate results thanks to the knowledge of the network environment.

Monitoring modern networks involves storing and transferring huge amounts of data. For this reaso... more Monitoring modern networks involves storing and transferring huge amounts of data. For this reason, compression techniques are typically used in order to reduce the space and time needed for these operations. The main drawback of this approach is that, when data has to be processed, a preliminary decompression is necessary, which increases the time and computational power needed. To cope with this problem, in this paper we propose a technique that allows to transform the measurement data in a representation format meeting two main objectives at the same time. Firstly, it allows to perform a number of operations directly on the transformed data with a controlled loss of accuracy, thanks to the mathematical framework it is based on. Secondly, the new representation has a small memory footprint, allowing to reduce the space needed for data storage and the time needed for data transfer. To validate our technique, we perform an analysis of its performance in terms of accuracy and memory footprint. The results show that the transformed data closely approximates the original data (within 5% relative error) while achieving the compression ratio of 20%; storage footprint can be gradually made close to that of the state-of-theart compression tools, such as bzip2, if higher approximation is allowed.

ABSTRACT The paper is the first step towards the goal of evaluating the measurement uncertainty o... more ABSTRACT The paper is the first step towards the goal of evaluating the measurement uncertainty of the inter-departure times (IDT) provided by software traffic generator. The paper is focused on the experimental characterization of the internal generation cycle of a well-known, open source generator, namely D-ITG, for different systems, and under the best possible conditions, i.e. with the minimum system loads. The resulting performance may be seen as the ideal limit the generator can tend to. The extended abstract presents the rationale for the activity, the underlying methodology and some initial tests that highlight the relevance of the clock resolution in the accuracy of IDT.

Modeling and Optimization in Mobile, Ad-Hoc and Wireless Networks, 2010

Cellular technology is widely used for Internet access, also because most operators are now offer... more Cellular technology is widely used for Internet access, also because most operators are now offering Mbit/s data rates at affordable prices. Many studies analyzed the performance of these networks using analytical or simulation approaches. However, due to lack of data from operational environments, very little is known about the performance of real cellular networks. In this paper, we assess the

In this paper we present our traffic generation platform, named D-ITG (Distributed Internet Traff... more In this paper we present our traffic generation platform, named D-ITG (Distributed Internet Traffic Generator). Its features are first described. We believe that some capabilities are in fact innovative, since no other traffic generator offers them. Then, we describe the original architecture of D-ITG, which allows our traffic generator to achieve high performance. We hint at a comparison with other traffic generators and conclude with the ongoing work to add new features.

In this Technical Report we report our activities on the Design, Implementation, and Testing of a... more In this Technical Report we report our activities on the Design, Implementation, and Testing of a Hybrid Tool for Network Topology Discovery we called Hynetd.

Computer Networks, 2013

Nowadays, Cloud Computing is widely used to deliver services over the Internet for both technical... more Nowadays, Cloud Computing is widely used to deliver services over the Internet for both technical and economical reasons. The number of Cloud-based services has increased rapidly and strongly in the last years, and so is increased the complexity of the infrastructures behind these services. To properly operate and manage such complex infrastructures effective and efficient monitoring is constantly needed.

IEEE GLOBECOM 2008 - 2008 IEEE Global Telecommunications Conference, 2008

Networked embedded systems are gaining more and more attention and their use in current network s... more Networked embedded systems are gaining more and more attention and their use in current network scenarios is of indisputable importance. Research community and industry are proposing novel embedded solutions, often based on network processors, for network connectivity, data processing and service delivery. Despite this, quantitative performance comparisons of such systems seem to be very hard to find. In this paper, we describe an experimental analysis of different boards for networked embedded systems using both general-purpose and network processors, and running both commercial and open source operating systems. The results show that network-processor based boards are able to attain very high performance when compared to boards based on x86 processors, especially when running commercial operating systems. The analysis provides a reference for the design, development, and testing of novel networked embedded systems.

2014 International Conference on Future Internet of Things and Cloud, 2014

2012 Eighth International Conference on Signal Image Technology and Internet Based Systems, 2012

Understanding the ever-changing scenario of computer networks and how they operate in the real wo... more Understanding the ever-changing scenario of computer networks and how they operate in the real world implies measuring and analyzing their characteristics. This in turn requires a set of advanced tools and methodologies to be shared among researches, along with the data derived from such activities. In this paper we first present some of the main issues and challenges in the field of Internet Monitoring and Measurement, then we present several open source platforms we have developed in the last 10 years for monitoring heterogeneous and large scale networks. Finally, we describe some of the data sets we made publicly available to the research community.

In this Technical Report we report our activities on the Design, Implementation, and Testing of a... more In this Technical Report we report our activities on the Design, Implementation, and Testing of a Hybrid Tool for Network Topology Discovery we called Hynetd.

Future Generation Computer Systems, 2015

Even if Internet traffic analysis and characterization is a fer- tile research area, a lot of wor... more Even if Internet traffic analysis and characterization is a fer- tile research area, a lot of work still must be done to study and understand the traffic characteristics of new emerg- ing multimedia applications. Among them, an interesting category is that of multiplayer network games. This pa- per aims at demonstrating that, at packet level, spatial and temporal invariants exist

Computer Networks, Jan 1, 2009

In this paper we present our traffic generation platform, named D-ITG (Distributed Internet Traff... more In this paper we present our traffic generation platform, named D-ITG (Distributed Internet Traffic Generator). Its features are first described. We believe that some capabilities are in fact innovative, since no other traffic generator offers them. Then, we describe the original architecture of D-ITG, which allows our traffic generator to achieve high performance. We hint at a comparison with other traffic generators and conclude with the ongoing work to add new features.

Software Defined Networking (SDN) is an emerging paradigm that is expected to revolutionize compu... more Software Defined Networking (SDN) is an emerging paradigm that is expected to revolutionize computer networks.
With the decoupling of data and control plane and the introduction of open communication interfaces between layers, SDN enables programmability over the entire network, promising rapid innovation in this area.
The SDN concept was already proven to work successfully in cloud and data center environments thus the proper monitoring of such networks is already in the focus of the research community.
Methods for measuring Quality of Service (QoS) parameters such as bandwidth utilization, packet loss, and delay have been recently introduced in literature, but they lack a solution for tackling down the question of \emph{available bandwidth}.
In this paper, we attempt to fill this gap and introduce a novel mechanism for measuring available bandwidth in SDN networks.
We take advantage of the SDN architecture and build an application over the Network Operating System (NOS).
Our application can track the topology of the network and the bandwidth utilization over the network links, and thus it is able to calculate the available bandwidth between any two points in the network.
We validate our method using the popular Mininet network emulation environment and the widely used NOS called Floodlight.
We present results providing insights into the measurement accuracy and showing its relationship with the delay in the control network and the polling frequency.

In the field of network monitoring and measurement, the efficiency and accuracy of the adopted to... more In the field of network monitoring and measurement, the efficiency and accuracy of the adopted tools is strongly dependent on (i) structural and dynamic characteristics of the network scenario under measure and (ii) on manual fine tuning of the involved parameters. This is, for example, the case of the endto-end available bandwidth estimation, in which the constraints of the measurement stage vary according to the use of the final results. In this work we present UANM (Unified Architecture for Network Measurement), a novel measurement infrastructure for an automatic management of measurement stages, tailored to the end-to-end available bandwidth estimation tools. We describe in details its architecture, illustrating the features we introduced to mitigate the problems affecting available bandwidth estimation in heterogeneous scenarios. Moreover, to provide evidences of UANM benefits, we present an experimental validation in three selected scenarios deployed over a real network testbed: (i) we show how UANM is able to alleviate the interferences among concurrent measures; (ii) we quantify the overhead introduced by the use of UANM; (iii) we illustrate how UANM is capable to provide more accurate results thanks to the knowledge of the network environment.

Monitoring modern networks involves storing and transferring huge amounts of data. For this reaso... more Monitoring modern networks involves storing and transferring huge amounts of data. For this reason, compression techniques are typically used in order to reduce the space and time needed for these operations. The main drawback of this approach is that, when data has to be processed, a preliminary decompression is necessary, which increases the time and computational power needed. To cope with this problem, in this paper we propose a technique that allows to transform the measurement data in a representation format meeting two main objectives at the same time. Firstly, it allows to perform a number of operations directly on the transformed data with a controlled loss of accuracy, thanks to the mathematical framework it is based on. Secondly, the new representation has a small memory footprint, allowing to reduce the space needed for data storage and the time needed for data transfer. To validate our technique, we perform an analysis of its performance in terms of accuracy and memory footprint. The results show that the transformed data closely approximates the original data (within 5% relative error) while achieving the compression ratio of 20%; storage footprint can be gradually made close to that of the state-of-theart compression tools, such as bzip2, if higher approximation is allowed.

ABSTRACT The paper is the first step towards the goal of evaluating the measurement uncertainty o... more ABSTRACT The paper is the first step towards the goal of evaluating the measurement uncertainty of the inter-departure times (IDT) provided by software traffic generator. The paper is focused on the experimental characterization of the internal generation cycle of a well-known, open source generator, namely D-ITG, for different systems, and under the best possible conditions, i.e. with the minimum system loads. The resulting performance may be seen as the ideal limit the generator can tend to. The extended abstract presents the rationale for the activity, the underlying methodology and some initial tests that highlight the relevance of the clock resolution in the accuracy of IDT.

Modeling and Optimization in Mobile, Ad-Hoc and Wireless Networks, 2010

Cellular technology is widely used for Internet access, also because most operators are now offer... more Cellular technology is widely used for Internet access, also because most operators are now offering Mbit/s data rates at affordable prices. Many studies analyzed the performance of these networks using analytical or simulation approaches. However, due to lack of data from operational environments, very little is known about the performance of real cellular networks. In this paper, we assess the

IEEE Transactions on Instrumentation and Measurement, 2014

ABSTRACT This paper is a first step toward the goal of evaluating the measurement accuracy of the... more ABSTRACT This paper is a first step toward the goal of evaluating the measurement accuracy of the interdeparture times (IDTs) provided by software traffic generators. To provide evidences of the proposed methodology, in this paper, we focus our attention on the experimental characterization of the internal generation cycle of a well-known, open source generator, namely, distributed internet traffic generator. We tested the traffic generator for different systems, and under the best possible conditions, i.e., with the minimum system load. The resulting performance may be seen as the ideal limit the generators can tend to. In this paper, we present the rationale for the activity, the underlying methodology and a set of tests aimed at highlighting the relevance of the clock resolution in the accuracy of IDT. In addition, we present a statistical model for the IDT of packets. The model allows to capture the effects of the various phenomena that affect this important generation parameter. We have also performed a set of experiments with another traffic generator to show the generalizability of the results. These results show that the contributions proposed in this paper are general and valid for a wide set of software-based traffic generators.

IEEE Global Communications Conference (Globecom), 2019

With the growing adoption of cloud infrastructures to deliver a variety of IT services, monitorin... more With the growing adoption of cloud infrastructures to deliver a variety of IT services, monitoring cloud network performance has become crucial. However, cloud providers only disclose qualitative info about network performance, at most. This hinders efficient cloud adoption, resulting in no performance guarantees, uncertainties about the behavior of hosted services, and sub-optimal deployment choices. In this work, we focus on cloud-to-user latency, i.e. the latency of network paths interconnecting datacenters to worldwide-spread cloud users accessing their services. In detail, we performed a 14-day measurement campaign from 25 vantage points deployed via Planetlab infrastructure (emulating spatially-spread users) and considering services running in distinct locations on the infrastructures of the two most popular public-cloud providers, namely Amazon Web Services and Microsoft Azure. Our experimentation allows to provide an in-depth performance characterization (based on multiple probing methods and fine-grained sampling rate) of such networks as perceived by users spread worldwide. Results show the presence of both spatial and temporal latency trends. Finally, by evaluating the advantages of multi-cloud deployments, our results also provide useful guidelines to cloud customers.