Author: Iljitsch van Beijnum

Apple's Worldwide Developers Conference starts with a keynote, but the rest of the week is about sessions that go into much more depth with Apple's software. During a session named Networking for the Modern Internet (video requires Safari, or you can look it up in the iOS WWDC app), Apple Distinguished Engineer, Scientist, and Technologist Stuart Cheshire took the stage to explain new networking features in iOS 10 and macOS Sierra. Soon the engineer revealed what developers can do to take full advantage of ECN, IPv6, international text in networking, cellular versus Wi-Fi, and network quality of service.

IPv6

Last year, Apple told iOS developers that IPv6-only cell service is coming soon, get your apps ready. As of June 2015, iOS applications were required to support IPv6. Apparently iOS developers are taking Apple's advice to heart: use higher level APIs, because those automatically use either IPv4 or IPv6 depending on what's appropriate.

Apple says that as many as 70 percent of connections to www.apple.com from certain ISPs (like Verizon Wireless) come in over IPv6. About 40 percent of connections from Belgium, the world leader in IPv6 deployment, come in over IPv6. More and more big websites are finding that page load times over IPv6 are faster than over IPv4. For instance, Facebook is seeing 45 percent IPv6 HTTP requests, which complete 15 to 30 percent faster than IPv4 requests.

Twenty years ago this month, RFC 1883 was published: Internet Protocol, Version 6 (IPv6) Specification. So what's an Internet Protocol, and what's wrong with the previous five versions? And if version 6 is so great, why has it only been adopted by half a percent of the Internet's users each year over the past two decades?

10 percent!

First the good news. According to Google's statistics, on December 26, the world reached 9.98 percent IPv6 deployment, up from just under 6 percent a year earlier. Google measures IPv6 deployment by having a small fraction of their users execute a Javascript program that tests whether the computer in question can load URLs over IPv6. During weekends, a tenth of Google's users are able to do this, but during weekdays it's less than 8 percent. Apparently more people have IPv6 available at home than at work.

Google also keeps a map of the world with IPv6 deployment numbers per country, handily color-coded for our convenience. More and more countries are turning green, with the US at nearly 25 percent IPv6, and Belgium still leading the world at almost 43 percent. Many other countries in Europe and Latin America and even Canada have turned green in the past year or two, but a lot of others are still stubbornly staying white, with IPv6 deployment figures well below one percent. Some, including China and many African nations, are even turning red or orange, indicating that IPv6 users in those countries experience significantly worse performance than IPv4 users.

Earlier in the year, our own Sebastian Anthony had the opportunity to experience the new "IMAX with laser" cinema in Leicester Square, and it didn't disappoint. Not to be outdone, Dolby Laboratories invited Ars UK to the new JT cinema with Dolby Cinema in Hilversum, the broadcasting capital of the Netherlands.

Middle-aged Ars readers may remember Dolby from the Dolby B noise reduction system used with cassette tapes. Younger Ars readers are probably more familiar with Dolby through Dolby Digital, the codec used to encode most digital audio on DVDs as well as TV broadcasts and Blu-ray discs. (Dolby Digital started out as a way to add digital surround sound to film, where the digital information is encoded on the unused space between the perforations of the 35mm film, where it can be read optically.)

The latest Dolby audio technology in cinemas is Dolby Atmos, which supports a few more audio tracks than older systems—128 of them, in fact. However, Dolby Atmos improves upon previous surround sound technologies not by simply adding more channels. Instead, it allows sounds to be dynamically placed in a 3D space. This is used to great effect when noisy objects fly over the audience; it sounds very realistic. To allow for these effects, the JT cinema in Hilversum has no fewer than 60 speakers on the walls and the ceiling of its Dolby Cinema-equipped auditorium. Dolby Atmos is currently installed in several thousand cinemas worldwide and films such as Spectre and the new Star Wars are available with a Dolby Atmos mix (in compatible cinemas).