Simulation of Mixed Critical In-vehicular Networks

Future automotive applications ranging from advanced driver assistance to autonomous driving will largely increase demands on in-vehicular networks. Data flows of high bandwidth or low latency requirements, but in particular many additional communication relations will introduce a new level of complexity to the in-car communication system. It is expected that future communication backbones which interconnect sensors and actuators with ECU in cars will be built on Ethernet technologies. However, signalling from different application domains demands for network services of tailored attributes, including real-time transmission protocols as defined in the TSN Ethernet extensions. These QoS constraints will increase network complexity even further. Event-based simulation is a key technology to master the challenges of an in-car network design. This chapter introduces the domain-specific aspects and simulation models for in-vehicular networks and presents an overview of the car-centric network design process. Starting from a domain specific description language, we cover the corresponding simulation models with their workflows and apply our approach to a related case study for an in-car network of a premium car

Economic FAQs About the Internet

This is a set of Frequently Asked Questions (and answers) about the economic, institutional, and technological structure of the Internet. We describe the history and current state of the Internet, discuss some of the pressing economic and regulatory problems, and speculate about future developments.Internet, telecommunications, congestion pricing, National Information Infrastructure

Resource dimensioning through buffer sampling

Link dimensioning, i.e., selecting a (minimal) link capacity such that the users’ performance requirements are met, is a crucial component of network design. It requires insight into the interrelationship among the traffic offered (in terms of the mean offered load , but also its fluctuation around the mean, i.e., ‘burstiness’), the envisioned performance level, and the capacity needed. We first derive, for different performance criteria, theoretical dimensioning formulas that estimate the required capacity $c$ as a function of the input traffic and the performance target. For the special case of Gaussian input traffic, these formulas reduce to $c = M + \alpha V$, where directly relates to the performance requirement (as agreed upon in a service level agreement) and $V$ reflects the burstiness (at the timescale of interest). We also observe that Gaussianity applies for virtually all realistic scenarios; notably, already for a relatively low aggregation level, the Gaussianity assumption is justified.\ud As estimating $M$ is relatively straightforward, the remaining open issue concerns the estimation of $V$. We argue that particularly if corresponds to small time-scales, it may be inaccurate to estimate it directly from the traffic traces. Therefore, we propose an indirect method that samples the buffer content, estimates the buffer content distribution, and ‘inverts’ this to the variance. We validate the inversion through extensive numerical experiments (using a sizeable collection of traffic traces from various representative locations); the resulting estimate of $V$ is then inserted in the dimensioning formula. These experiments show that both the inversion and the dimensioning formula are remarkably accurate

NGA, IP-Interconnection and their Impact on Business Models and Competition

Developments towards Next Generation Networks (NGN) have a strong impact on the design of the markets for electronic communications in general, but specifically on intercarrier relations with respect to interconnection and access. Due to the fact that competition in the European telecommunications environment has brought about alternative providers and their business models it is an interesting area to investigate how these business models will develop in an NGN environment and which (additional) business models may emerge in the future. To that end, the current paper looks at the development of different business models in the PSTN world and likely developments in the NGN world. This leads to conclusions with respect to requirements of the future regulatory framework of next generation networks in order to maintain the achievements of competition in the telecommunications area.NGN, business models, migration, competition, regulatory framework

NGA, IP-Interconnection and their Impact on Business Models and Competition

Developments towards Next Generation Networks (NGN) have a strong impact on the design of the markets for electronic communications in general, but specifically on intercarrier relations with respect to interconnection and access. Due to the fact that competition in the European telecommunications environment has brought about alternative providers and their business models it is an interesting area to investigate how these business models will develop in an NGN environment and which (additional) business models may emerge in the future. To that end, the current paper looks at the development of different business models in the PSTN world and likely developments in the NGN world. This leads to conclusions with respect to requirements of the future regulatory framework of next generation networks in order to maintain the achievements of competition in the telecommunications area.NGN, business models, migration, competition, regulatory framework.

Resource dimensioning through buffer sampling

Link dimensioning, i.e., selecting a (minimal) link capacity such that the users’ performance requirements are met, is a crucial component of network design. It requires insight into the interrelationship between the traffic offered (in terms of the mean offered load M, but also its fluctuation around the mean, i.e., ‘burstiness’), the envisioned performance level, and the capacity needed. We first derive, for different performance criteria, theoretical dimensioning formulae that estimate the required capacity C as a function of the input traffic and the performance target. For the special case of Gaussian input traffic these formulae reduce to C = M+V , where directly relates to the performance requirement (as agreed upon in a service level agreement) and V reflects the burstiness (at the timescale of interest). We also observe that Gaussianity applies for virtually all realistic scenarios; notably, already for a relatively low aggregation level the Gaussianity assumption is justified.\ud As estimating M is relatively straightforward, the remaining open issue concerns the estimation of V . We argue that, particularly if V corresponds to small time-scales, it may be inaccurate to estimate it directly from the traffic traces. Therefore, we propose an indirect method that samples the buffer content, estimates the buffer content distribution, and ‘inverts’ this to the variance. We validate the inversion through extensive numerical experiments (using a sizeable collection of traffic traces from various representative locations); the resulting estimate of V is then inserted in the dimensioning formula. These experiments show that both the inversion and the dimensioning formula are remarkably accurate

Building consensus on Internet access at the Internet Governance Forum (IGF)

This paper identifies and documents the main areas of discussions and 'recommendations' that were generated under the Access theme at the second Internet Governance Forum in Rio De Janeiro, November 2007. Whilst recognising that the IGF is currently viewed and operates primarily as a space for discussion, the paper finds that (specifically in the case of Access) it is also a space in which commonality of opinion occurs to the level at which 'recommendations' can be made and repeatedly asserted independently/individually in the workshops, and strategically reinforced at different levels of the IGF. The Internet Governance Forum (IGF) is a space for multi-stakeholder policy dialogue, set up in 2006 as a direct response to the deliberations of the World Summit on the Information Society (WSIS). The forum was created to (amongst other things) discuss public policy issues related to key elements of internet governance in order to foster the sustainability, robustness, security, stability and development of the internet. Its structure, function and working are addressed in paragraphs 73 to 79 of the WSIS Tunis Agenda