+********************************************************************** * * * Einladung * * * * Informatik-Oberseminar * * * +**********************************************************************

Zeit: Dienstag, 2. Juli 2019, 11.30 Uhr Ort: Seminarraum 9007, Gebäude E3, Ahornstr. 55

Referent: Torsten Zimmermann, M.Sc. Lehrstuhl Informatik 4

Thema: Improving Content and Service Distribution beyond Infrastructure Upgrades

Abstract: The Internet has evolved into an essential platform for communication and access to information. This manifests itself in the steadily growing traffic due to rising user demands for content and services. However, these demands put pressure on operators to constantly improve performance and availability, e.g., by upgrading infrastructures. Despite these efforts, there are limits to upgrades and their impact, ranging from technical to economic aspects. To still achieve improvements, research also focuses on other aspects of content and service distribution, including protocol optimization, better infrastructure utilization, and approaches to overcome limited infrastructure support.

However, these optimizations can have unknown consequences in real-world deployments. Even if protocols underwent a rigorous standardization process, their adoption and impact are often unpredictable. The same holds for approaches that support infrastructures, which face practical challenges when deployed outside of testbeds, e.g., missing user acceptance due to the lack of control. Overcoming these challenges is relevant to achieve improvements beyond the current state-of-the-art solutions.

In this talk, we approach the problem of how to provide improvements for content and service distribution beyond infrastructure upgrades from the aforesaid viewpoints: the deployment of a new protocol and the applicability of supporting approaches. We provide the first large-scale adoption study of HTTP/2, as the new standard protocol for the Web, and especially focus on its promising new feature Server Push. Despite being considered a key feature of HTTP/2, we observe that its use does not always lead to improvements, but also to human-perceivable detrimental effects, which we verified in a user study. Building on this, we further inspect which factors influence performance and provide a novel strategy for the use of this feature, which can lead to significant performance improvements.

Focusing on how to support infrastructures, we present an approach that enables roaming mobile users to connect to private Access Points, using provider-assisted authentication and the creation of an on-demand single purpose network. By that, we provide connectivity in case other infrastructures, such as the cellular network, are temporarily not available. Finally, we provide a brief outlook on how to realize content distribution between devices with only limited infrastructure support.

In summary, our contributions provide valuable insights and practical technical solutions that complement infrastructure-based improvements.

Es laden ein: die Dozentinnen und Dozenten der Informatik