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#809: Wi-Fi, the Cloud, and your Newsstand


Greetings! And happy…spring?

Last weekend, New Hampshire got the most snow we have seen since the big one from last October. Some areas got 4-6 inches, while northern parts of the state got more, but this is the longest that the snow has actually stayed on the ground. That is due to change though, as temperatures rise into the 50s and possibly the 60s later this week. Not sure what Punxsutawney Phil thinks of all this, but as a motorcycle rider, I say bring on the warm weather!

This week, we bring you articles on Wireless Networking standards, keeping control over your online magazine subscriptions and a follow-up to a previous article to address some reader concerns.

The day is almost upon us! Keep an eye on our Barkings! blog for the latest information on the next iPad! Will it be the iPad 3? iPad HD? The rumor sites are saying it will do everything but wash your car (although there may be an app for that later).


  Wi-Fi basics  

What is Wi-Fi?

Modern networking has slowly come of age, replacing wired interfaces with wireless connections governed by IEEE 802.11 standards. 802.11 communications function the same as wired connections, with the OSI physical layer moving from a hard wired connection to wireless broadcast and the OSI data link layer using the CSMA/CA (Carrier Sense Multiple Access with Collision Avoidance) protocol to regulate the transmissions of data. CSMA/CA, to prevent packet collision, listens to a channel for a predetermined amount of time to see if the channel is in use. If the channel is determined to be idle, the node is allowed to start broadcasting.

Some of the early 802.11 standards, 802.11a, set forth rules of wireless operation in the 5GHz range supporting data transmission upwards of 54Mbit/second. (With error correction, maximum practical attainable data transmission was around 27Mbit/s). 802.11a used OFDM, Orthogonal Frequency Division Multiplexing, dividing the data to be transmitted up over 52 subcarriers in the 5GHz range. This broadcast method is called broadcasting in parallel. One of 802.11a major drawback was range when compared to 802.11b; maximum transmission distances reaching 60 feet.

802.11b, ratified in 1999, operates in the 2.4GHz radio frequency band. It can attain data transmission speeds of up to 11Mbit/s and has a theoretical range of 300 feet. Unlike the OFDM of the 802.11a, the broadcast of 802.11b was controlled by DSSS or Direct Sequence Spread Spectrum. DSSS, OSI layer 1, sequences the data across any one or multiple 22MHz band in the 2.4GHz set.

In June of 2003, 802.11g was ratified. 802.11g was the third Wi-Fi standard ratified after 802.11a and b. It functions on the 2.4GHz range like 802.11b but uses ODFM like 802.11a to attain speeds of 54Mbit/s. 802.11g can optionally use DSSS for backwards compatibility with 802.11b. The range of 802.11g is slightly less than that of 802.11b, theoretically broadcasting upwards of 300 feet.

Used in draft form since 2007 and becoming a standard in 2009, 802.11n uses a little from all of the above. 802.11n operates in both the 2.4GHz and 5.0GHz ranges. For higher throughput it added MIMO (Multiple-Input Multiple-Output) antennas to the package. The theoretical transmission rate with 802.11n was up to 600Mbit/s, 150Mbit/s across 4 channels. It, too, uses OFDM to distribute data across multiple carrier frequencies.

  Cancel My Subscription  

Since getting an iPad I’ve slowly moved all my old analog reading material into the digital world. I’ve been very slowly obtaining digital versions of books that I have in print form, and with the advent of Newsstand, I’m now able to get nearly every magazine I read on the iPad as well. Many of them I’ve been getting in Zinio (a good app and a good service), but the app versions have the potential to be much more interactive than what I believe can be obtained through Zinio.

I encountered something this past weekend that lead me to an idea for a tip for you, our readers. I had one magazine that I wasn’t particularly enjoying but had inadvertently signed up for a recurring monthly subscription. Each time the magazine came through I’d read it, get disappointed and think to myself, “I should really cancel this subscription.” I’d look through the magazine’s preferences to find an unsubscribe button of some kind, but always to no avail. Then I’d get distracted by something shiny and I’d forget all about the magazine for another month…

This time, I was determined not to be beaten by a poorly designed app and a short attention span. I did a little Googling and discovered that the subscription preferences aren’t in the magazine itself but in the iOS App Store. That makes sense, right? (I didn’t think so either.)

Here’s what you do:

  • Tap on the App Store
  • Tap on Purchased at the bottom
  • Tap on your Apple ID
  • Tap View Apple ID
  • Enter your password
  • Tap Manage (under Subscriptions)

Here you can manage how your subscriptions will be renewed. It’s so tucked away you’d think you were using Android. Needless to say, that magazine will no longer be polluting my Newsstand.

  Synchronization 102  

I received a question from a longtime reader asking me how comfortable I was with Wi-Fi synchronizing of apps versus using a cloud method. It’s a legitimate question; suddenly all our private data, normally kept within our own local network, is now being sent out to the Internet for (potentially) all to see. How safe is the data we’re putting out there?

iCloud automatically encrypts your data as it is copied, so anything flying through the airwaves is not likely to be grabbed by someone with a packet sniffer. With wireless networking, however, the encryption has to be set up when the network is created. If you have a wireless network that does not require a password to connect to it, there is no encryption of the data as it passes over the wireless. If you’re not the person who set up the network, the encryption level is out of your control. (Some applications may do their own encryption, but the network itself does not.) While an open network is sometimes okay for the average home user, a business should never use an unencrypted wireless network for transmitting data.

Of note was 1Password—where it used to require local syncing, now it can sync via Dropbox. How safe is this? Dropbox uses the same level of encryption used by financial institutions, i.e. Secure Sockets Layer (SSL) and AES-256 bit encryption. In addition, 1Password uses encryption for your password file. The only way to unlock the file is with your master password. Rather than re-explain it, here’s the info from Agile’s page.

In the case of iCloud, your data is encrypted both in transmission and storage, most likely using your Apple ID’s password as part of the encryption key. Apple’s article about it is here. In theory, anything you put up on iCloud is secure enough for most people. If you are seriously concerned about privacy, you can always use some other encryption program on your files before sending it to the cloud (regardless of whose cloud you use.) This would probably only apply to documents; I can’t think of any reason why music files would need to be encrypted. This does not apply to Wi-Fi sync via iTunes however—anything you sync between your computer running iTunes and your iOS device is subject to the same encryption (if any) as is used by your wireless network.

Personally, I use both Wi-Fi sync for my iPhone as well as iCloud for keeping all my stuff the same across systems. The key part is that at some point, you have to place your trust in the company providing the service. Apple created not only our Macs, but also the OS we’re using, and we trust that they aren’t putting in any backdoors to collect our stuff. (If they were, you can bet that it would be all over the news.)

Security is a big buzzword now; where people years ago knew nothing and cared less, now everyone is aware that data needs to be protected (some even tipping towards the fanatical side). On the other hand, we have always suspected that Google and Facebook are collecting private information, yet we continue to use them regularly. One would assume Apple would never risk its reputation by intentionally collecting personal data.

In my mind, it’s really no different than handing your credit card to a restaurant server. How do you know that card isn’t being taken into the back room and copied for later use? Restaurants are places that have been in existence for years, so there is an inherent trust. Large computer companies that have been in business for as long as Apple and Microsoft tend to garner trust in its users (although you will always have the conspiracy theorists who assume ANY large corporation is up to no good.)

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