New Ebook! A Practical Guide to Networking and Security in iOS 8

Hey, you can buy this book!

I wrote a book! Well, a revision. It soft launched on Friday, and will be more broadly announced on Monday. If you find yourself in need of step-by-step instructions, troubleshooting, or explanations about using networking options or security features and add-ons in iOS 8 on an iPhone or iPad — do I have a book for you! It's called A Practical Guide to Networking and Security in iOS 8.

It's $15, but you, dear blog reader and friend, receive a whopping 25% off with this coupon: E18CFOG. For that price, you get the PDF, EPUB, and MOBI (Kindle compatible) formats, plus free updates to this edition covering iOS 8. And you can read on any device: I don't believe in encrypted books, because the rights-management locks just hinder legitimate readers.

It covers AirDrop, AirPlay, Bluetooth, Wi-Fi, WPA2, VPNs, Personal (and Instant) Hotspot, and a lot more, all with friendly instructions and illustrated steps. You can read all about it, including seeing the table of contents and downloading an excerpt at my book site.

(If you bought an earlier version in the Take Control series (covering iOS 4 or 6), wait for email from Take Control Books, as they'll have a sweeter discount for previous buyers.)

This is the first book I think I've ever released solo, and it stands on the shoulders of friends and colleagues. The first two editions that I wrote were developed with Tonya Engst and Michael E. Cohen at Take Control Books. This revision, I turned to Jeff Carlson for technical and copy editing and Scout Festa for proofreading. Christa Mrgan designed the cover graphic.

And Tonya and her husband Adam and I are testing releasing books like mine through their Take Control library. Because this book wasn't in high demand, but sold fine, I decided to update it on my own, and they can make it available to their customers, while I can sell it directly too! A win all around.

Recent Writing and Podcasts (mid-January to late February)

On the heels of the news that I'll be writing (and talking) more about Macworld, here's a summary of recent articles and podcasts there and all over.



  • Macworld podcast #445: My first appearance as co-host! We talked about Google's updated Wallet offering with cell carriers, malware in hard drive firmware, solar farms and data centers, and new emoji.
  • Clockwise #75: Apple Car, government spying, Samsung spying, and Apple's greatest threats.

Big Hair to Fill

You may have heard that veteran Macworld staffer Chris Breen joined a fruit company in the Bay Area. (Raisins? Apricots?) Chris spent 30 years as writer, and nearly 20 at Macworld. With him gone, who would fill his big hair…I mean, shoes?

Who has two thumbs and eight other fingers and loves writing about Mac stuff? No, not Two Thumbs Eight Fingers McGee. (I hate that guy.) Me! Because I'm not in California, it didn't work out to take over his job. Instead, in addition to the security and privacy column I've written weekly for Macworld since late September, I'll be co-hosting the weekly Macworld podcast with executive editor Susie Ochs and other Macworld staff, and writing the Mac 911 column, where reader questions are researched and answered. You should subscribe to the podcast right now, shouldn't you?

It's a good shift for me, as a long-time senior contributor for Macworld. I've written…I don't know how many articles for Macworld. Hundreds? It'll be a pleasure to have more recurring gigs there, especially the podcast, as I've been trying to get back into regular audio work. (The podcast I launched with Christina Bonnington, Not Enough Time in the Week, has to go on hiatus, as there's too much of a topic overlap with what we'll be talking about in the Macworld podcast, sadly!)

What does this mean for my other writing? Oh, don't you worry. You'll still find me at Fast Company, the Economist, Boing Boing, and other publications. I have books in progress and a new one coming out this week on networking and security in iOS 8. With the funding nearly complete for The Magazine: The Complete Archives, a combination of my time and outside help will get that out the door by April.

And Old & New, my fresh periodical idea, will still launch as planned: as a blog with commissioned articles and a podcast. I'd always intended to launch it slowly but steadily, instead of all at once with the money and time commitment required for that.

It will be nice to have a solid anchor at Macworld, reducing the amount of time I spend pitching stories, many of which don't turn into assignments, and instead spend more time being productive in a way that benefits other people.

Phase Fresnel Lenses and the Long History of Optics

I file a lot of stories, and very occasionally one doesn't work out. The below explanation of phase Fresnel lenses is one of them. I couldn't hit the right tone for its original destination, and shopped it around, but it wasn't quite a fit anywhere. Enjoy this look into lighthouses, lenses, and the history of optics.

Cape Mears lighthouse in Oregon, now decommissioned and run by volunteers. Photo by yours truly.

Nikon Puts a Lighthouse in Your Pocket

Nikon is at the forefront of techniques to produce complex camera lenses that enable shorter, lighter barrels.

Augustin-Jean Fresnel's crowning achievement was a proof of diffraction that earned him the French Grand Prix in 1819. But it was his later work with refraction in lighthouses that secured him a lasting place on the lips of mariners and theatre stagehands alike. Nikon has taken both aspects of Fresnel's work to produce a new 300mm telephoto lens that is 30% shorter and 40% lighter than its preceding model, while improving all its capabilities.

Fresnel perfected the theory that a lens focuses light passing through it without the need of a continuous curve on the far side: the angle is all that matters. Thus, a lens can be divided into an infinite number of portions of the curve, each of which provides the appropriate focusing path for beams of light. In practice, a Fresnel lens is a set of discontiguous segments, often arrayed in concentric circular ridges, with stepped intervals at each boundary parallel to the direction of the light source.

Fresnel put this theory into wide-scale practice in his role as France's commissioner of lighthouses. Before the use of these lenses, lighthouses both made inefficient use of light, directing roughly 40% from an electric lamp of the day out to the ocean, which would carry weakly from 12 to 20 miles. Larger lenses were more difficult to cast and grind, and hard to transport and mount safely at the treacherous locations at which lighthouses typically sit.

The new lenses under Fresnel's design were not only lighter through the removal of extraneous thickness, but also were constructed in segments, which allowed the use of different kinds of lenses and replacement of individual pieces without losing the entire light. Sigils were designed by rotating a lens around a light with different colored panels, which allowed sailors to identify the origin of each light while far at sea.

Fresnel raised the efficiency to about 80%, while also collimating it long before lasers. A light could be now be seen brightly at over 20 miles (32 km) away. While Fresnel isn't celebrated by sailors the way that Samuel Plimsoll is — for his championing of a line on ships indicating their safe-loading level — he deserves it, too.

Nikon's use of a Fresnel lens also has to do with color, but in a quite different fashion. Normal refractive lenses focus light of different wavelengths at different points, with red (longer wavelength) focusing farthest and blue closest. This causes chromatic aberration, typically corrected with intermediate lenses.

Encyclopædia Britannica, 1911

Encyclopædia Britannica, 1911

However, a phase Fresnel (PF) lens introduces diffraction, as each of the concentric rings of the lens is an obstacles around which light waves bend. This diffraction inverts the chromatic aberration, putting blue closest and red farthest. The concentric rings are spaced at extremely small intervals — tinier than the wavelength of light — to produce the desired diffraction effect.

By pairing a PF element and a refractive element, the combined PF lens corrects the aberration, while reduces the number and weight of lenses and the overall focal distance needed for magnification compared to more conventional lens arrays. In cases of extremely bright spot light sources, a PF lens can cause ring-shaped color flares, and Nikon offers an in-camera software option to mitigate the effect.

The theory of phase Fresnel dates back to at least an academic paper in 1961, and has been applied to X-ray and gamma-ray observation among other purposes. Nikon first experimented with PF over a decade ago, says Steve Heiner, a senior technical manager at Nikon. In that case, the lens was a compact and lightweight small diameter telephoto add-on to a lower-end digital camera.

Nikon also uses a PF lens in some of its microscope products, and competitor Canon introduced a more straightforward Fresnel lens in 2001 that didn't carry with it all the advantages of weight and length.

This new 300mm lens, however, is aimed at the high-end consumer and professional market, where it replaces a fixed (or "prime") telephoto lens that's been a mainstay of Nikon's line for decades, and marks the introduction of phase Fresnel to a bigger, albeit rarified audience. Mr Heiner says the goal was to create a lens with all of the enhancements Nikon had developed over the last two decades as well as reduce the weight and length.

The new model, which started shipping recently as the "AF-S NIKKOR 300MM f/4E PF ED VR" and retails for $2,000, includes a three-axis anti-vibration motor that effectively increases the lens' speed by 4.5 stops, allowing for blur-free photos at slower shutter speeds, among other combinations. For outdoor photographers, the light weight and stabilisation mitigate the need for a monopod or tripod, aiding in portability.

While not a lighthouse in appearance or design, Nikon's news lens is a direct descendent of Fresnel's science — a 21st century realization of a 19th century's genius. And it should take great shots to boot.

iWatch, iHub

I had a vision this morning of where the Apple Watch fits into the bigger universe of things. As I said at the launch, this first version is not what Apple intends to make at all. It will have a highly interested but likely limited audience, and it will make huge margins on the top end of the basic watches plus the premium ones, like gold.

The ultimate form of the Watch comes when it can contain all the sensors and radios of a current iPhone. That's probably within two years — Watch 3. Most of the improvements in battery performance in an iPhone go to power bigger and denser and brighter screens. In a Watch, the power needs for a cellular radio (multiple standards), Wi-Fi, GPS, and MEMS (accelerometer, gyroscope, etc.) will likely be low enough by then and the chips advanced enough to work.

In that view, the Watch stops being an adjunct to a phone, but the pivot point around which the Apple universe turns, which you can see in its use as enabling Apple Pay for some phone models. The Watch becomes:

  • The key to your house, that turns off your alarm.
  • The tracker of your health, which is already planned in the first release.
  • The way you pay, but no longer with a phone.
  • The thing you have and thing you are (biometric) for two-step or two-factor authentication.
  • The entertainment hub for your car, which no longer needs a radio/receiver unit at all, but just a surface-mounted magnetic charging dock against which you place your Watch while driving.
  • What you use to stream and remotely control audio and video to your AirPlay devices.
  • How you unlock your Mac or phone.

HomeKit, HealthKit, Apple Pay, AirPlay, CarPlay, Touch ID, iCloud. The Watch is the digital hub around which everything rotates in the new Apple universe.

A phone, a tablet, a car screen, an HDTV, a monitor, a Mac display — these all become the extensions of the same digital identity that the Watch facilitates managing. You may no longer need a phone, but the focus shift from a phone to the Watch as your pivot point. That's the transition Apple expects to make.

There Is Not Enough Time in the Week for My New Co-Hosted Podcast!

I've been absent from a regular podcast for a while as I wrapped up The Magazine and sorted out my freelance career. But I'd been incubating an idea for a while, and enlisted my friend, Christina Bonnington, a staff writer at Wired, to co-host Not Enough Time in the Week. She and I have complementary technical backgrounds and interests, and we'll quiz each other each week to explain the events of the last few days — why is China blocking VPNs (and what is a VPN)? If Uber is planning self-driving cars, is that realistic in the near future? The FCC is changing how it defines broadband, and what does that mean and how will it change our available services?

We're looking forward to listener feedback and suggestions. We're keeping it timely and short: 30 to 40 minutes per episode. Give a listen below, or find us via our RSS feed or on iTunes.

Crowdfunding The Magazine: The Complete Archives

Never let it be said that I do things by half measures: I've launched a Kickstarter campaign to fund producing the complete archives of The Magazine, the publication I edited and then purchased, in ebook form. It will be nearly 300 articles and over 500,000 words, and may be so large I split it into several files to avoid clogging ereaders and ebook software.

We had a remarkable range of articles and contributors, and this campaign will let me collect it all in one place, and then make it available forever through ebookstores and beyond. Thanks for considering being part of it!

FCC Telegraphs Decision with Strong Letter on Wi-Fi Blocking

The FCC may be telegraphing (sorry) its position on how it will handle the Marriott et al. petition in which the hotel giant, a real-estate trust, and the hotel industry trade group argues that they have a right to create false traffic to block Wi-Fi networks on their premises in the interests of service quality and security. The FCC's press release today opens with:

WARNING: Wi-Fi Blocking is Prohibited
Persons or Businesses Causing Intentional Interference to Wi-Fi Hot Spots Are Subject to Enforcement Action

(As the old joke goes: "strong letter follows!")

As I explained in late December at Boing Boing, Marriott's initial petition was broad, technically inaccurate in places, and asserted definitions and rights that aren't available for use in the unlicensed spectrum. Marriott &co. earlier in January filed a comment that backed off from many claims in its petition, but as far as I can tell either didn't or isn't allowed to withdraw or amend the original proposal. The chain paid $600,000 to settle an investigation and agreed to an FCC consent decree that requires it to report on its actions.

Many comments from companies and individuals have also been filed, most of which harangue hoteliers for wanting to block the use of personal (smartphone/tablet) and portable (MiFi-like) hotspots to preserve a cash cow of in-room and event Internet fees.

However, the IT community is somewhat concerned, as the technique Marriott employed is part of a suite of tools used to keep the radio-frequency (RF) environment in a building, corporate campus, or academic campus clean and functional. Personal and portable hotspots can contribute to reducing throughput or making networks less functional. I was part of a great discussion on the Packet Pushers podcast about the extent to which those devices cause problems, and how this situation will shake out.

The FCC's WARNING would indicate that it won't side with Marriott, or even with Cisco, which filed a comment suggesting that a limited ability to block "rogue" networks for very specific reasons would be useful.

The Enforcement Bureau has seen a disturbing trend in which hotels and other commercial establishments block wireless consumers from using their own personal Wi-Fi hot spots on the commercial establishment’s premises. As a result, the Bureau is protecting consumers by aggressively investigating and acting against such unlawful intentional interference.

The memo notes the FCC has received reports of similar blocking elsewhere and urges people to file a complaint if Wi-Fi blocking is suspected (via 1-888-CALL-FCC or its complaints form).

This is a positive move for preventing hotels and others from seizing control over spectrum they don't own or license, and it's a good affirmation of individual rights as well. But it doesn't solve the spectrum usage problem, nor clarify what IT people outside of public accommodations, like hotels, should do. The rogue-blocking software they use may be illegal, based on the Marriott consent order and then this follow-up. As co-panelist on the Packet Pushers, Lee Badman, tweeted today:

Read Lee's post for more insight on what network administrators are faced with. As Lee noted on the podcast, the lack of guidelines for co-existence of tens of millions of tiny, often high-powered movable hotspots with fixed Wi-Fi networks has caused a collision. Marriott's solution isn't the right one — but some path forward that doesn't criminalize an IT administrator will be needed.

Update: Later in the day, the FCC chair, Tom Wheeler, stated unequivocally:

Consumers must get what they pay for. The Communications Act prohibits anyone from willfully or maliciously interfering with authorized radio communications, including Wi-Fi. Marriott’s request seeking the FCC’s blessing to block guests’ use of non-Marriott networks is contrary to this basic principle.

An FCC commissioner also stated today that she would like the FCC to dismiss the Marriott petition "quickly."

Apple Updates To Fix Some Annoyances

Apple released OS X and iOS updates today with a little more verbosity than they have in recent years. Yosemite 10.10.2 includes a Wi-Fi disconnection fix, and we'll see if that finally nails a bug that dates back to beta testing and has driven some people bananas. I've seen it in roaming problems in my house, in which Yosemite won't hand off from one base station to another, despite a poor signal. Several other items in the list appeared in my or the mega-comments for The Software and Services Apple Needs to Fix.

The iOS 8.1.3 fix repairs several issues, including the bug I've seen repeatedly in which apps are not searchable via Spotlight—they don't show up in results. This is a four-month-long bug for a feature I and others may use multiple times a day. (It didn't always fail, but it did at least once a day for me.)