Convergence of Probability Measures. By P. Billingsley. Chichester, Sussex, Wiley, 1968. xii, 253 p. 9 1/4“. 117s.

Convergence of Probability Measures

Social Network Analysis

The Internet has led to the creation of a digital society, where (almost) everything is connected and is accessible from anywhere. However, despite their widespread adoption, traditional IP networks are complex and very hard to manage. It is both difficult to configure the network according to predefined policies, and to reconfigure it to respond to faults, load, and changes. To make matters even more difficult, current networks are also vertically integrated: the control and data planes are bundled together. Software-defined networking (SDN) is an emerging paradigm that promises to change this state of affairs, by breaking vertical integration, separating the network's control logic from the underlying routers and switches, promoting (logical) centralization of network control, and introducing the ability to program the network. The separation of concerns, introduced between the definition of network policies, their implementation in switching hardware, and the forwarding of traffic, is key to the desired flexibility: by breaking the network control problem into tractable pieces, SDN makes it easier to create and introduce new abstractions in networking, simplifying network management and facilitating network evolution. In this paper, we present a comprehensive survey on SDN. We start by introducing the motivation for SDN, explain its main concepts and how it differs from traditional networking, its roots, and the standardization activities regarding this novel paradigm. Next, we present the key building blocks of an SDN infrastructure using a bottom-up, layered approach. We provide an in-depth analysis of the hardware infrastructure, southbound and northbound application programming interfaces (APIs), network virtualization layers, network operating systems (SDN controllers), network programming languages, and network applications. We also look at cross-layer problems such as debugging and troubleshooting. In an effort to anticipate the future evolution of this new paradigm, we discuss the main ongoing research efforts and challenges of SDN. In particular, we address the design of switches and control platforms—with a focus on aspects such as resiliency, scalability, performance, security, and dependability—as well as new opportunities for carrier transport networks and cloud providers. Last but not least, we analyze the position of SDN as a key enabler of a software-defined environment.

https://publications.uni.lu/bitstream/10993/20596/1/survey_on_SDN.pdf

Software-Defined Networking: A Comprehensive Survey

Infectious Diseases Society of America.

The structure and dynamics of multilayer networks

Due to scalability issues that the current Internet is facing, the research community has re-discovered the Locator/ID Split paradigm. As the name suggests, this paradigm is based on the idea of separating the identity from the location of end-systems, in order to increase the scalability of the Internet architecture. One of the most successful proposals, currently under discussion at the IETF, is LISP (Locator/ID Separation Protocol). A critical component of LISP, from a performance and resources consumption perspective, as well as from a security point of view, is the LISP Cache. The LISP Cache is meant to temporarily store mappings, i.e., the bindings between identifiers and locations, in order to provide routers with the knowledge of where to forward packets. This paper presents a thorough analysis of such a component, based on real packet-level traces. Furthermore, the implications of policies to increase the level of security of LISP are also analyzed. Our results prove that even a timeout as short as 60 seconds provides high hit ratio and that the impact of using security policies is small.

/pdf/a-deep-dive-into-the-lisp-cache-and-what-isps-should-know-hhqtydac7v.pdf

A deep dive into the LISP cache and what ISPs should know about it

The evolution of wireless network standards, e.g., GSM/GPRS, UMTS, WiFi, WiMAX, and end-user devices has paved the way towards Next Generation Mobile Networks (NGMN), where users are always connected through multiple radio access networks. NGMN technologies target to improve the user experience especially for mobile data and multimedia services, which are in line with user expectations evident from, for instance, the increasingly popular mobile HTTP video streaming. To understand the quality that can be offered to the user in NGMNs, we compare the Quality of Experience (QoE) for HTTP streaming in a prototype NGMN testbed with WiFi and 3G UMTS/HSDPA support. We use CUBIC TCP as the transport layer protocol as it is typically the default TCP variant, e.g., in Android phones. We complement the QoE estimations with network QoS parameters such as throughput and delay, and transport layer statistics. The results of our evaluation show that (i) video QoE remains stable in WiFi even for high packet losses compared to UMTS, (ii) QoE in UMTS is sensitive to packet loss even for low loss rates due to high variations in the network QoS, namely, throughput and delay, (iii) the decrease in QoE and QoS in HSDPA is due to its negative interactions with the aggressive congestion control of CUBIC TCP, and (iv) handover from WiFi to HSDPA degrades QoE.

/pdf/understanding-cross-layer-effects-on-quality-of-experience-1w6z6zc588.pdf

Understanding Cross-Layer Effects on Quality of Experience for Video over NGMN

Software-Defined Networks (SDNs) are typicallydesigned and operated under the assumption that the underlyingrouters (and switches) are trustworthy. Recent incidents, however, suggest that this assumption is questionable. The possibility ofincorrect or even malicious router behavior introduces a widerange of security problems. The problem is exacerbated by thefact that governments and companies do not have the expertisenor budget to build their own trusted high-performance routinghardware. This paper presents NetCo, an approach to build securerouting using insecure routers. NetCo is inspired by the robustcombiner concept known from cryptography, and leveragesredundancy to compile a secure whole from insecure parts. Wepresent the basic design of NetCo, and report on a prototypeimplementation in OpenFlow.

NetCo: Reliable Routing With Unreliable Routers

Consumer Internet of Things (IoT) devices are extremely popular, providing users with rich and diverse functionalities, from voice assistants to home appliances. These functionalities often come with significant privacy and security risks, with notable recent large scale coordinated global attacks disrupting large service providers. Thus, an important first step to address these risks is to know what IoT devices are where in a network. While some limited solutions exist, a key question is whether device discovery can be done by Internet service providers that only see sampled flow statistics. In particular, it is challenging for an ISP to efficiently and effectively track and trace activity from IoT devices deployed by its millions of subscribers --all with sampled network data. 
In this paper, we develop and evaluate a scalable methodology to accurately detect and monitor IoT devices at subscriber lines with limited, highly sampled data in-the-wild. Our findings indicate that millions of IoT devices are detectable and identifiable within hours, both at a major ISP as well as an IXP, using passive, sparsely sampled network flow headers. Our methodology is able to detect devices from more than 77% of the studied IoT manufacturers, including popular devices such as smart speakers. While our methodology is effective for providing network analytics, it also highlights significant privacy consequences.

A Haystack Full of Needles: Scalable Detection of IoT Devices in the Wild

In the past a series of staining procedures for proteins were published. Still, the most commonly used staining dye for proteins is Coomassie Brilliant Blue. The major reason is that Coomassie Brilliant Blue staining is simple, fast, and sensitive. As Coomassie Brilliant Blue is almost insoluble in water a series of procedures including colloidal aqueous procedures has been described.

Anja Feldmann

Papers

A deep dive into the LISP cache and what ISPs should know about it

Understanding Cross-Layer Effects on Quality of Experience for Video over NGMN

NetCo: Reliable Routing With Unreliable Routers

A Haystack Full of Needles: Scalable Detection of IoT Devices in the Wild

Coomassie Brilliant Blue Staining of Polyacrylamide Gels