Computer performance is a bit
of a shell game. You're always waiting for one of four things:
Disk
CPU
Memory
Network
But which one? How long will you wait? And what will you do while you're
waiting?
Did you see the movie
"Her"? If not, you should. It's great. One of my favorite scenes is the AI
describing just how difficult it becomes to communicate with humans:
It's like I'm reading a book… and it's a book I deeply love. But I'm reading
it slowly now. So the words are really far apart and the spaces between the
words are almost infinite. I can still feel you… and the words of our story… but
it's in this endless space between the words that I'm finding myself now. It's a
place that's not of the physical world. It's where everything else is that I
didn't even know existed. I love you so much. But this is where I am now. And
this who I am now. And I need you to let me go. As much as I want to, I can't
live your book any more.
I have some serious reservations about the work environment pictured in Her
where everyone's spending all day creepily whispering to their computers, but
there is deep fundamental truth in that one pivotal scene. That infinite space
"between" what we humans feel as time is where computers spend all
their time. It's an entirely different timescale.
The book Systems Performance:
Enterprise and the Cloud has a great table that illustrates just how
enormous these time differentials are. Just translate computer time into
arbitrary seconds:
1 CPU cycle
0.3 ns
1 s
Level 1 cache access
0.9 ns
3 s
Level 2 cache access
2.8 ns
9 s
Level 3 cache access
12.9 ns
43 s
Main memory access
120 ns
6 min
Solid-state disk I/O
50-150 μs
2-6 days
Rotational disk I/O
1-10 ms
1-12 months
Internet: SF to NYC
40 ms
4 years
Internet: SF to UK
81 ms
8 years
Internet: SF to Australia
183 ms
19 years
OS virtualization reboot
4 s
423 years
SCSI command time-out
30 s
3000 years
Hardware virtualization reboot
40 s
4000 years
Physical system reboot
5 m
32 millenia
The above Internet times are kind of optimistic. If you look at the AT&T
real time US internet latency chart, the time from SF to NYC is more like
70ms. So I'd double the Internet numbers in that chart.
Latency is one thing, but it's also worth considering the cost of that
bandwidth.
Speaking of the late, great Jim Gray,
he also had
an interesting way of explaining this. If the CPU registers are how long it
takes you to fetch data from your brain, then going to disk is the
equivalent of fetching data from Pluto.
He was probably referring to traditional spinning rust hard drives, so let's
adjust that extreme endpoint for today:
Distance to Pluto: 4.67 billion miles.
Latest fastest spinning HDD performance (49.7)
versus latest fastest PCI Express SSD (506.8).
That's an improvement of 10x.
New distance: 467 million miles.
Distance to Jupiter: 500 million miles.
So instead of travelling to Pluto to get our data from disk in 1999,
today we only need to travel to … Jupiter.
That's disk performance over the last decade. How much faster did CPUs,
memory, and networks get in the same time frame? Would a 10x or 100x improvement
really make a dent in these vast infinite spaces in time that computers deal
with?
To computers, we humans work on a completely different time scale,
practically geologic
time. Which is completely mind-bending. The faster computers get, the bigger
this time disparity grows.
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Tuesday, April 7, 2015
All developers want to see their mobile apps take off. But it’s what happens
after all the hard work, testing and final prep—and when—that can make
or break their chances of success. Especially when it comes to launching and
promoting those apps.
See also: iOS
Apps Generated More Revenue Than Hollywood Movies Last
Year
Timing is everything, according to app marketing and optimization firm Sensor
Tower. Its
new report on iOS apps, released Friday, suggests that weekends are the best
time to plug those apps, in general. In most categories, that’s when people use
them, make purchases and download new ones the most.
But not all apps and target audiences are the same, and results can vary from
one type of app to another.
When We Buy, When We Download, And Why
Knowing when people are most likely to buy or download apps, and reaching
them in those critical moments could be the critical difference between a
lackluster showing and a runaway hit.
Sensor Tower, which supplies analytics and marketing insights, tasked its
Data Science team with analyzing download figures and app revenue estimates for
iOS apps in the U.S. across the first three months of this year.
We totaled the estimated weekly downloads and revenue for all iOS apps in the
US, for each category. Then we broke down the downloads and revenue by day to
see what percentage of the weekly total happened on each day.
Drilling down into the data, the team compared the daily breakdowns to
identify the optimal days to promote apps across App Store categories.
In most cases, the findings lined up with common sense: Weekends were
generally the best day to promote apps, particularly when it came to
lifestyle-oriented apps.
See also: Apple
Watch Developers Can Now Submit Watch Apps To
Apple
But if people care about fun on the weekends, then they're all about work
during the week, with business apps doing well Monday through Friday. While they
were at the office, they also tended to download finance apps, though they used
them and made purchases through them on weekends. Users also tried to keep
productivity up pretty consistently across the week and weekends, with usage and
revenue holding fairly steady.
Medical apps, however, offer sporadic results. They peaked in downloads on
Sundays, but for revenue, they inexplicably hopped between Sunday to Wednesday
and Thursday.
To drill down into the data further or explore other app categories, check
out Sensor Tower’s report.
Timing App Launches
The information should help hone marketing efforts, particularly when it
comes to plugging previously released applications. Timing and promoting an app
launch or new update, might be trickier.
iPhone app makers often don’t always know precisely when Apple will approve
their apps and funnel them into the App Store. While the company offers a tool that
shows what percentage of apps have been approved over the preceding 5 days on
its developer site, the
company also states that, “because every app submitted is different, there’s
no set review time.”
According to Shiny Development, which collects information based on community
feedback, App Store reviews take 8 days
on average for mobile apps. (For Mac applications, the process takes just 5
days.)
That’s much better than the months-long delays and opaque communication Apple
used to put developers through a few years ago. But it’s still no comparison to
the two to three hours it takes Android developers to breeze through Google
Play’s review process. And if Apple takes issue with anything, the complication
could stretch out that timeline even further.
Following the App Store
Review Guidelines to the letter should help streamline things as much as
possible. In addition, Apple offers a way for developers to set
a future release date for their apps. If they allow plenty of time for
review, they can plan their marketing activities accordingly. It also wouldn’t
hurt to cross those fingers and hope no problems come up that derail things.
Then maybe, just maybe, they can actually take advantage of the launch window
to hit that weekend rush. Lead photo by Jason A Howie;
charts courtesy of Sensor Tower
Earlier this week, Google unveiled
the Chromebit—a Chrome OS computer the size of a candy bar that plugs into a
TV's HDMI port. This device, manufactured by Asus, is the latest in a line of
“computers on a stick,” a type of gadget we're likely to see a lot more of.
The Chromebit joins a handful of several similar devices that have slowly
been gaining momentum over the past few years. Most of these run Android,
although Intel recently announced a
Windows-on-a-stick device as well. Together, it's not inconceivable these
little gadgets could jumpstart a sticky computer revolution—one in which desktop
computing all but disappears into a tiny gadget you can plug into any screen you
want.
Sure, they may seem like novelties now. But some students and office workers
could be packing computer sticks before too long. You might even end up with one
in your living room.
Here's your guide for navigating what just might be a big stick shift.
It's A Stick-Up
Google envisions the Chromebit as an inexpensive way for businesses or
schools to replace aging desktops without having to buy entirely new computers.
(Asus hasn't released a price yet, although Google says the Chromebit will be
"less than $100.") Instead of buying a new desktop or laptops that need to be
secured, you could just plug Chromebits into existing monitors and carry
on—assuming, of course, you don't need local apps beyond what's available for
Chrome OS.
That, of course, is where Intel's Compute Stick could come in, as a full
Windows 8 computer for $150. You could even imagine an office or classroom
equipped with a monitor and a wireless keyboard at every chair. All a user would
have to do is plug in their stick computer of choice, connect to the local
Wi-Fi, and they’re ready to work.
Schools have already started embracing portable computing. In 2014, I taught
at a school that provided a free iPad with every student’s tuition. The iPads
provided access to the students’ textbooks, and Microsoft had recently released
Office for iPad, meaning they could write essays using the Word app. (Of course,
the iPad’s inherent limitations as a productivity machine meant that they were
usually running Candy Crush Saga rather than Evernote.)
The
iPad: not a valuable productivity solution.
Take it a step further and it's also easy to see how stick computers might
also serve as home entertainment centers. A stick plugged into your living room
TV could easily stream TV and movies and run at least some games, although
possibly not the most demanding ones. With the Chromebit, it's also possible to
outsource heavy lifting to a more powerful computer, since you can arrange to
control it via the Chrome Remote Desktop app.
People will undoubtedly figure out other ways to get on the stick as the
devices spread. The real question is which stick computer makes the most sense
for any particular scenario.
Chromebit vs. Android
The Chromebit will reportedly
sport a Rockchip 3288 processor, 2GB of RAM, and 16GB of internal flash storage
with Wi-Fi and Bluetooth 4.0/LE connectivity, not to mention a micro USB port
for power and a full USB port for any other peripherals you want to attach.
But at first glance, it’s hard to figure out why a Chrome OS stick should be
any more appealing than one
of the dozens of Android OS sticks currently on the market—many of which
have similar specs but lower
price tags. After all, there are far more Android apps than Chrome OS apps
available.
This
"Android Mini PC" from Timingpower is one of many similar devices from no-name
companies.
But with the advent of the ARC
Welder beta from Google, developers have more tools than ever to start
porting Android apps to Chrome with ease. Apps likely won’t be an issue for
long.
Single-screen
multitasking on Chrome OS
Chrome OS’s real advantage over Android is single-screen multitasking.
Introduced to Chrome OS in 2012, the ability to have more than one program
running on the screen at a time basically sets “real” computers apart from
mobile devices.
An iPad restricts users to one app on-screen making it more about fun than
productivity. And except for a few specific handsets like the LG G3 and a few
Samsung Galaxy phones and phablets, there really aren’t any Android devices that
handle multiple apps on screen at the same time. (And those that do, generally
don't do it all that gracefully.)
Windows Sticks, Too
Before we even first saw the Chromebit, Intel announced
its plans to release the Compute Stick, a $150 dongle that runs Windows 8
and packs an Atom processor, 2GB of RAM, and 32GB of internal storage.
Intel's
Compute Stick runs full Windows 8.1 or Linux
(If you’re into penguins, Intel will also release a version that runs Linux;
it comes with the same RAM and storage for $110.)
Like the Chromebit, the Compute Stick comes with Bluetooth and Wi-Fi
connectivity, along with a micro USB power port and a full USB port for plugging
in other peripherals. Perhaps most important, it'll give users access to the
full array of Windows software and apps, and can easily handle multiple windows.
Both versions of the Compute Stick are available
for pre-order, with a ship date of April 24.
Some lesser-known companies have released Windows sticks, though they may not
be worth your time. A company called Mouse Computer has a Windows 8 stick of its
own set
to debut in Japan in late April; the m-Stick comes
with a microSD card slot and an internal fan for $175. There’s also the $120
Windows 8 Wintel Mini PC from a company called Vensmile, and a dubious
looking dual-Android/Windows stick from MeeGoPad
that apparently comes with an unlicensed version of Windows 8 with Chinese
system messages.
The
Mouse Computer m-Stick, which runs Windows 8.1, will launch in Japan in late
April.
Still, Windows is Windows, and the complication of managing software and
configurations—the natural consequence of a more complex operating system—could
be more trouble than its worth if distributing stick computers to a large number
of users at a school or office.
The Sticking Point
Ultimately, your choice of what stick computer will come down to what kind of
work needs to get done and what programs will suit that work best. The good news
is that there will probably be even more options before too long, since we’re
only at the beginning of the stick computer movement—if it does turn out to be a
movement, that is.
It’s still entirely possible that these HDMI dongles will fail to catch on,
and we’ll toss stick computers away in the same dustbin as the world’s discarded
netbooks. When electronics become cheap and ubiquitous, it becomes that much
harder for them to retain any lasting value—and that much harder for them to
stick around.
On Monday, I was testing our Freedome
VPN for Windows and eventually… I forgot that I was using our London exit
node.
And then I attempted to log in to
Twitter.
This was the result:
And then I received this message via e-mail:
An unusual device or location?
In order to
determine that I was attempting to log in from an "unusual" location, Twitter
must be keeping a history of my previous IP addresses to compare against. This
type of security feature is not new, Facebook has been doing this sort of thing
for years already. But I've not yet seen it from Twitter. (A few years ago,
Twitter seemed to be actively against such an idea.) Unlike Facebook, I don't
see anyplace from which I can download my own connection history. Previous IP
addresses used are available to those who download a Facebook archive. But IP
address information isn't in the Twitter archive that I downloaded
today.
So then the questions I now have for Twitter is this: for how long
have my connections been logged and tracked? And when will a copy of the data be
available to me?
Twitter "may" receive information such as IP
address and will "either delete Log Data or remove any common account
identifiers" "after 18 months." The language about 18 months was first included
in version 5 of the policy, June 23, 2011.
The Internet of Things (IoT) devices can help you save time and hassle and
improve your quality of life. As an example, you can check the contents of your
fridge and turn on the oven while at the grocery store thus saving money,
uncertainty, and time when preparing dinner for your family. This is great and
many people will benefit from features like these. However, as with all changes,
along with the opportunity there are risks. Particularly there are risks to your
online security and privacy but some of these risks extend to the physical World
as well. As an example, the possibility to remotely open your front door lock
for the plumber can be a great time saver but it also means that by hacking your
cloud accounts it will be possible for also the hackers to open your door -- and
possibly sell access to your home on dark markets. And it's not just about
hacking: These gadgets collect data about what's happening in your home and life
and hence they themselves present a risk to your privacy.
Image: The above image shows a typical smart home
configuration and the kinds of attacks it can face. While the smart home is not
a target at the moment due to its low adoption rate and high fragmentation, all
of the layers can be attacked with existing techniques.
If you are
extremely worried about your privacy and security, the only way to really stay
safe is to not buy and use these gadgets. However, for most people, the
time-saving convenience benefits of IoT and the Smart Home will outweigh most
privacy and security implications. Also, IoT devices are not widely targeted at
the moment and even when they are, the attackers are after the computing power
of the device -- not yet your data or your home. Actually, the biggest risk
right now comes from the way how the manufacturers of these devices handle your
personal data. This all said, you shouldn't just blindly jump in. There are some
things that you can do to reduce the risks:
• Do not connect these
devices directly to public internet addresses. Use a firewall or at least a NAT
(Network Address Translation) router in front of the devices to make sure they
are not discoverable from the Internet. You should disable UPnP (Universal Plug
and Play) on your router if you want to make sure the devices cannot open a port
on your public internet address.
• Go through the privacy and security
settings of the device or service and remove everything you don't need. For many
of these devices the currently available settings are precious few, however.
Shut down features you don't need if you think they might have any privacy
implications. For example, do you really use the voice commands feature in your
Smart TV or gaming console? If you never use it, just disable it. You can always
enable it back if you want to give the feature a try later.
• When you
register to the cloud service of the IoT device, use a strong and unique
password and keep it safe. Change the password if you think there is a risk
someone managed to spy it. Also, as all of these services allow for a password
reset through your email account, make sure you secure the email account with a
truly strong password and keep the password safe. Use 2-factor authentication
(2FA) where available -- and for most popular email services it is available
today.
• Keep your PCs, tablets, and mobile phones clear of malware.
Malware often steals passwords and may hence steal the password to your smart
home service or the email account linked to it. You need to install security
software onto devices where you use the passwords, keep your software updated
with the latest security fixes, and, as an example, make sure you don't click on
links or attachments in weird spam emails.
• Think carefully if you
really want to use remotely accessible smart locks on your home doors. If you're
one of those people who leave the key under the door mat or the flower pot,
you're probably safer with a smart lock, though.
• If you install
security cameras and nannycams, disconnect them from the network when you have
no need for them. Consider doing the same for devices that constantly send audio
from your home to the cloud unless you really do use them all the time. Remember
that most IoT devices don't have much computing power and hence the audio and
video processing is most likely done on some server in the cloud.
• Use
encryption (preferably WPA2) in your home Wi-Fi. Use a strong Wi-Fi passphrase
and keep it safe. Without a passphrase, with a weak passphrase, or when using an
obsolete protocol such as WEP, your home Wi-Fi becomes an open network from a
security perspective.
• Be careful when using Open Wi-Fi networks such
as the network in a coffee shop, a shopping mall, or a hotel. If you or your
applications send your passwords in clear text, they can be stolen and you may
become a victim of a Man-in-the-Middle (MitM) attack. Use a VPN application
always when using Open Wi-Fi. Again, your passwords are they key to your
identity and also to your personal Internet of Things.
• Limit your
attack surface. Don't install devices you know you're not going to need. Shut
down and remove all devices that you no longer need or use. When you buy a top
of the line washing machine, and you notice it can be connected through Wi-Fi,
consider if you really want and need to connect it before you do. Disconnect the
device from the network once you realize you actually don't use the online
features at all.
• When selecting which manufacturer you buy your device
from, check what they say about security and privacy and what their privacy
principles are. Was the product rushed to the market and were any security
corners cut? What is the motivation of the manufacturer to process your data? Do
they sell it onwards to advertisers? Do they store any of your data and where do
they store it?
• Go to your home router settings today. Make sure you
disable services that are exposed to the Internet -- the WAN interface. Change
the admin password to something strong and unique. Check that the DNS setting of
the router points to your ISP's DNS server or some open service like OpenDNS or
Google DNS and hasn't been tampered with.
• Make sure you keep your
router's firmware up-to-date and consider replacing the router with a new one,
especially, if the manufacturer no longer provides security updates. Consider
moving away from a manufacturer that doesn't do security updates or stops them
after two years. The security of your home network starts from the router and
the router is exposed to the Internet.
The above list of actions is
extensive and maybe a bit on the "band-aid on the webcam"-paranoid side.
However, it should give you an idea of what kinds of things you can do to stay
in control of your security and privacy when taking a leap to the Internet of
Things. Security in the IoT World is not that different from earlier: Your
passwords are also very important in IoT as is the principle of deploying
security patches and turning off services you don't need.
Sure, smartphones and tablets get all the press, and deservedly so. But if
you place the original mainstream eInk device from 2007, the Amazon
Kindle, side by side with today's model, the evolution of eInk devices is
just as striking.
Each of these devices has a 6 inch eInk screen. Beyond that they're worlds
apart.
8" × 5.3" × 0.8" 10.2 oz
6.4" × 4.5" × 0.3" 6.3 oz
6" eInk display 167 PPI 4 level greyscale
6" eInk display 300 PPI 16 level
greyscale backlight
256 MB
4 GB
400 Mhz CPU
1 GHz CPU
$399
$199
7 days battery life USB
6 weeks battery life WiFi / Cellular
They may seem awfully primitive compared to smartphones, but that's part of
their charm – they are the scooter
to the motorcycle of the smartphone. Nowhere near as versatile, but as a form of
basic transportation, radically simpler, radically cheaper, and more durable.
There's an object lesson here in stripping things away to get to the core.
eInk devices are also pleasant in a paradoxical way because they
basically suck at everything that isn't reading. That doesn't sound
like something you'd want, except when you notice you spend every fifth page
switching back to Twitter or Facebook or Tinder or Snapchat or whatever. eInk
devices let you tune out the world and truly immerse yourself in
reading.
I believe in the broadest sense, bits > atoms.
Sure, we'll always read on whatever device we happen to hold in our
hands that can display words and paragraphs. And the advent of retina class
devices sure made reading a heck of a lot more pleasant on tablets and
smartphones.
But this idea of ultra-cheap, pervasive eInk reading devices eventually
replacing those ultra-cheap, pervasive paperbacks I used to devour as a kid has
great appeal to me. I can't let it go. Reading is
Fundamental, man!
That's why I'm in this weird place where I will buy, sight unseen, every new
Kindle eInk device. I wasn't quite crazy enough to buy the original
Kindle (I mean, look at that thing) but I've owned every model since the third
generation Kindle was introduced in 2010.
I've also been tracking the Kindle prices to see when they can get them down
to $49 or lower. We're not quite there yet – the basic Kindle eInk
reader, which by the way is still pretty darn amazing compared to that
original 2007 model pictured above – is currently on sale for $59.
But this is mostly about their new flagship eInk device, the Kindle Voyage.
Instead of being cheap, it's trying to be upscale. The absolute first thing you
need to know is this is the first 300 PPI (aka "retina") eInk reader
from Amazon. If you're familiar with the smartphone world before and
after the iPhone 4, then you should already be lining up to own one of these.
When you experience 300 PPI in eInk, you really feel like you're looking at a
high quality printed page rather than an array of RGB pixels. Yeah, it's still
grayscale, but it is glorious. Here are some uncompressed screenshots
I made from mine at native resolution.
Note that the real device is eInk, so there's a natural paper-like fuzziness
that makes it seem even more high resolution than these raw bitmaps would
indicate.
I finally have enough resolution to pick a thinner font than fat,
sassy old Caecilia.
The backlight was new to the original Paperwhite, and it definitely had some
teething pains. The third time's the charm; they've nailed the backlight aspect
for improved overall contrast and night reading. The Voyage also adds an ambient
light sensor so it automatically scales the backlight to anything from bright
outdoors to a pitch-dark bedroom. It's like automatic night time headlights on a
car – one less manual setting I have to deal with before I sit down and get to
my reading. It's nice.
The Voyage also adds page turn buttons back into the mix, via pressure
sensing zones on the left and right bezel. I'll admit I had some difficulty
adjusting to these buttons, to the point that I wasn't sure I would, but I
eventually did – and now I'm a convert. Not having to move your finger into the
visible text on the page to advance, and being able to advance without moving
your finger at all, just pushing it down slightly (which provides a
little haptic buzz as a reward), does make for a more pleasant and efficient
reading experience. But it is kind of subtle and it took me a fair number of
page turns to get it down.
In my experience eInk devices are a bit more fragile than tablets and
smartphones. So you'll want a case for automatic on/off and basic "throw it in
my bag however" paperback book level protection. Unfortunately, the official
Kindle Voyage case is a disaster. Don't buy it.
Previous Kindle cases were expensive, but they were actually very well
designed. The Voyage case is expensive and just plain bad. Whoever came
up with the idea of a weirdly foldable, floppy origami top opening case on a
thing you expect to work like a typical side-opening book should be
fired. I recommend something like this basic $14.99
case which works fine to trigger on/off and opens in the expected way.
It's not all sweetness and light, though. The typography
issues that have plagued the Kindle are still present in full force. It
doesn't personally bother me that much, but it is reasonable to expect more by
now from a big company that ostensibly cares about reading. And has a giant
budget with lots of smart people on its payroll.
This is what text looks like on a kindle.
— Justin Van Slembrou…
(@jvanslem) February 6,
2014
Companies are constantly on the lookout for new methods of interacting with
their customer base but it can be hard to integrate these with existing
systems.
Cloud communications firm Nexmo is launching a new API that allows a chat application to
interact with a customer service platform.
The Nexmo Chat App API helps brands consolidate all chat messages into their
existing communication platforms, eliminating the need to manually manage
communications over individual chat applications. The Chat App API does this by
automatically detecting and connecting brand messages with the appropriate chat
application in real time.
It lets marketing, sales or customer support staff send one message and have
it appear on all relevant chat applications at once. Nexmo also works directly
with each chat application to ensure messages appear correctly on all platforms.
In addition it informs brands which features are available on each chat
application. Through Nexmo's carrier relations it knows the cultural
restrictions in play on each network and can make them clear to brands.
"We live in an always-on world, where customers expect to be engaged anytime,
anywhere and on their preferred channels," says Nexmo CEO and co-founder, Tony
Jamous. "This means the bar for customer engagement has risen dramatically. At
the same time, solutions that are put in place need to be scalable, near real
time and cost efficient, and that’s where we see the tremendous opportunity for
the Chat App API. Adding the Chat App API to our portfolio of industry-leading
messaging and voice APIs transforms Nexmo from a company helping brands navigate
the current landscape of mobile communications to a resource that brands can
come to as customer communications dynamically changes shape".
The Nexmo Chat App API currently supports messaging on WeChat and Line. The
company will be adding support for additional chat apps, service platforms and
new features in the coming months. You can find out more and sign up for beta access on the Nexmo website.
Image Credit: Rawpixel / Shutterstock
