Deploying new TCP options takes time

TCP is an extensible protocol. Since the publication of RFC793, various TCP extensions have been proposed, specified and eventually deployed. When looking at the deployment of TCP extensions, one needs to distinguish between the extensions that provide benefits once implemented on senders and receivers and the implementations that need to be supported by both client and servers to be actually used.

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Even more bandwidth accross the oceans

Fiber optics play a key role in Wide Area Networks. With very small exceptions, most of the links that compose WANs are composed of optical fibers. As the demand for bandwidth continues to grow, network operators and large cloud companies continue to deploy new optical fiber links, both on the ground and accross the oceans. The latest announcement came from Microsoft and Facebook. Together, they have commissioned a new fiber optical link between Virginia Beach, Virginia (USA) and Bilbao, Spain. The landing points chosen for this fiber are a bit unusual since many of the fiber optic cables that cross the Atlantic Ocean land in the UK for obvious geographical reasons. This new cable brings 160 Terabits/sec of capacity and adds diversity to the fiber routes between America and Europe. This diveristy is beneficial against unexpected failures but also against organisations that captures Internet traffic by tapping optical fibers as revealed by Edward Snowden.

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Using public-key crypto remains difficult

Pretty Good Privacy, released in 1991, was probably one of the first software packages to make public-key cryptography available for regular users. Until then, crytography was mainly used by banks, soldiers and researchers. Public-key cryptography is a very powerful technique that plays a key role in securing the Internet. Despite of its importance, we still face issues to deploy it to all Internet users. The recent release of Adobe security team’s private key on a public web page is one example of this difficulty, but by far not the only one.

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Networking notes for readers of Computer Networking - Principles, Protocols and Practice

Networking education has changed a lot during the last twenty years. When a was still a student, before the invention of the web, students learned most from the explanations of their professors and teachning assistants. Additional information was available in scientific librairies, but few students could access it. Today’s students live in a completely different world. Computer networks and the Internet in particular have completely changed our society. Students have access to much more information that I could imagine when I was a student. Wikipedia provides lots of useful information, Internet drafts, RFCs and many scientific articles and open-source software are within the reach of all students provided that they understand the basics that enable them to navigate through this deluge of information.

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Beyond today's add-supported web

The web was designed in the 20th century as a decentralised technique to freely share information. The initial audience for the web protocols were scientific researchers who needed to share scientific documents. HTTP was designed as a stateless protocol and Netscape added HTTP cookies to ease e-commerce. These cookies play a crucial role in today’s ad-supported Internet. They have also enabled companies like Google or Facebook to collect huge amount of data about the browsing habits of almost all Internet users in order to deliver targeted advertisements.

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A 100-hops IPv6 wireless mesh

IPv6 is used for a variety of services. Wireless mesh networks are networks were routers use wireless links between themselves. This blog post describes such a large mesh network and provides several experiments conducted over it.

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