TagIFD

LINK LAYER

The lowest layer in the Internet protocol suite, and the one that is nearest to the physical medium that connects hosts together. The link layer is mostly responsible for communication to and from the physical medium, and to provide services to the internet layer. As such, the link layer is a bit primitive regarding other layers, but it provides important functionalities such as dealing with...

Reference models

We have insofar referred to idealized, generic versions of layers, services, and protocols. But how are they, really? You have learned in other courses that we can conceptualize communication within and between networks of systems via a model, the most famous of which is the OSI model, with its 7 layers. The seven layers were created by following the principles of identified needed abstraction...

Network Architecture

Networks are organized in stacks of layers. Each layer is built on top of the previous (below) one. The purpose of a layer is to offer services to the next (upper) one, and simultaneously, to shield the complexity of the previous (lower) layers. You know this concept in object-oriented programming: encapsulation. Indeed, layers are often imagined as hardware devices. While hardware is...

Network types

A network can be categorized according to several criteria. Among them there are the type of transmission and the network scope. The internet (lower case) is a particular type of network, classified by its scope. Transmission types Three types of transmission technology are in use today, i.e., unicast, multicast, and broadcast. Assume you have a sender system and a set of possible receivers, all...

Routes of the Internet

The Internet is made up of a number of independent Autonomous Systems, AS, operated by various organizations. These organizations can be an ISP, but also a company or a university. Intradomain routing, that is, routing inside the ASs, happens by following the AS rules and protocols. Interdomain routing, that is, routing between independent ASs, must happen by using the same protocol. That...

About Author

dgraziotin

Dr. Daniel Graziotin is a senior researcher (Akademischer Rat) at the University of Stuttgart, Germany. His research interests include human, behavioral, and psychological aspects of empirical software engineering, studies of science, and open science. He is associate editor at the Journal of Open Research Software and academic editor at the Research Ideas and Outcomes (RIO) journal. Daniel was awarded an Alexander von Humboldt Fellowship for postdoctoral researchers in 2017, the European Design Award (bronze) in 2016, and the Data Journalism Award in 2015. He received his Ph.D. in computer science at the Free University of Bozen-Bolzano, Italy.