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Broadband Caps May Obscure iCloud

Between iCloud’s sync services and the announcement that both Mac OS X Lion and iOS 5 would be available for download, it’s clear that Apple is envisioning a future where bandwidth is both cheap and plentiful. There’s no question that more people than ever have high-speed Internet connections and sprightly 3G data connections, but Apple’s plans may run smack dab into a countervailing trend: monthly usage caps and overage fees.

Because OS updates will range from hundreds of megabytes to several gigabytes, and iCloud could potentially move many gigabytes to and from the Internet every month, crossing bandwidth limits could suddenly become a costly or difficult issue. If you’re already running close to bandwidth limits with your current usage (such as streaming movies from Netflix or playing bandwidth-intensive games), adding iCloud could put you over the top.

With the introduction of monthly limits to AT&T’s wired broadband service in May 2011, more than half of U.S. home broadband subscribers now have some kind of cap. Some firms, like AT&T, charge for usage above a set amount, like 100 GB or 250 GB per month; others, like Comcast, with its 250 GB monthly limit, give you a warning the first time you exceed your limit, and then cancel your service if you get a second warning within a year.

Mobile broadband has long had restrictions in place, with tiered service plans offering only a few hundred megabytes to a gigabyte or two. T-Mobile in the United States, like many carriers in the rest of the world, throttles your bandwidth to tens of kilobytes per second if you cross its limits; others charge you or cut you off. (Verizon Wireless’s iPhone plan is the current exception, and is expected to shift to a tiered plan shortly, as the company offers with its other smartphones.)

Let’s look at how each of Apple’s promised services might use your limited bandwidth.

  • PC Free iOS 5 and Updates: Previously, all iOS updates were downloaded to your Mac or PC via iTunes, and installed via a USB sync. However, one of the major new features of iOS 5 is the elimination of the computer requirement. That’s convenient, but iOS 5 will undoubtedly weigh in at hundreds of megabytes, if not more, and even if Apple issues updates as relatively small patches, they’ll still be quite hefty. We imagine that iOS updates will be limited to Wi-Fi, since a single one would exceed most mobile broadband data plans.

  • Wi-Fi Sync: Apple carefully avoids using 3G data for the new Wi-Fi Sync feature coming in iOS 5 — the name gives that away, of course. Wi-Fi Sync is intended for local file copying only on the same Wi-Fi network as a computer to which you sync video and photo albums. To use it elsewhere (over 3G or Wi-Fi), Apple would have to enable remote access to your computers. Wi-Fi Sync doesn’t perform actions that count against your broadband usage, either. No worries there. (You may wish to upgrade to an 802.11n-capable base station, though. Newer iOS devices can run about two to four times faster over 802.11n than 802.11g.)

  • Synchronization and Backup: The “Apps, Books, and Backup” features of iCloud are potentially more worrying in relation to broadband caps. Apple limits backups and restores to Wi-Fi networks, but with the new PC Free approach, backups are stored in the cloud, and restore operations don’t seem to consult any local network copies. Instead, all apps, music, and books — but not videos and movies — purchased from iTunes are restored over the Internet and over the air. That could mean gigabytes of data to transfer from iCloud. Be especially careful if you use a MiFi for 3G-based Internet access for a Wi-Fi iPad, for instance, since then iOS can’t tell that you’re burning 3G data bits — it only knows it’s using Wi-Fi.

  • iTunes in the Cloud: By default, iTunes in the Cloud uses only Wi-Fi, but you can enable 3G as well. Given that music files are generally several megabytes each, syncing a large number over 3G could be ruinously expensive. Apple is clearly attempting to limit bandwidth usage, and any songs you have purchased and synced via iTunes to an iOS device won’t require a new download when you enable iTunes in the Cloud. But on devices on which the file doesn’t reside, or when you switch the music on a given device, iCloud has to perform new transfers. Be very careful syncing music.

  • Photo Stream: As with Wi-Fi Sync, iCloud’s Photo Stream feature that syncs photos among Macs and iOS devices works only over Wi-Fi networks. With modern day cameras creating file sizes in the multiple megabytes per photo, Photo Stream could consume quite a bit of bandwidth, especially given the number of photos that some people take.

  • Initial Setup: If you opt to prime a new iOS device with a huge iTunes library while on a network with a copy of iTunes that has an overlap or superset of the same music, it’s not clear whether your device will use Wi-Fi Sync or retrieve the contents from iCloud directly. Wi-Fi Sync would reduce bandwidth consumption, but Apple says nothing about it being used for the initial sync. You may wish to use USB for the initial sync to sidestep this conundrum.

  • Mac OS X Lion and Updates: Finally, if you think iOS 5 is going to drain bits from your bandwidth bucket, you haven’t seen anything until you want to upgrade to Lion. Although we still believe Apple will provide some alternative method of acquiring Lion if you don’t have a sufficiently big Internet pipe, Apple has released no details on that yet (see “Questions Raised by Lion’s App Store Installation Requirement,” 8 June 2011). The Lion download will undoubtedly be several gigabytes, and updates won’t be small either. Each computer has to download the installer separately, according to reports; the installer is deleted after installation, requiring a new retrieval for each machine!

It’s unlikely that iCloud services would, on their own, let you cross any mobile broadband caps unless you fooled it by using a personal hotspot like the MiFi. But iCloud could add several gigabytes, or even tens of gigabytes, of broadband transfer on top of your existing habits, and Lion and iOS 5 will only add to your bandwidth needs. In short, as you ease into using all of Apple’s new operating systems, keep an eye on whatever usage graphs or alerts your broadband provider offers.


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Comments about Broadband Caps May Obscure iCloud
(Comments are closed.)


By the looks of it, iCloud bandwidth is not going to be an issue for me, simply because I won't be able to install Lion if that really is an App Store only download.

I can't get fixed line broadband where I am, Apple Stores don't exist here (and I won't use another public Wi Fi system to install an operating system upgrade) and my monthly 3G data cap is 4 GB.


Cheers, Gobit
Do you not know what delta updates are? Only the parts of the OS that actually have changed will need to be downloaded. Not the whole thing.
Glenn Fleishman  An apple icon for a TidBITS Staffer 2011-06-06 16:34
"Updates won't be small" is our supposition based on OS X releases. There are frequently 1 GB updates to Snow Leopard which are, in fact, deltas. If you have a few machines, and are near your limit, and download a few 1 GB updates, it adds up.
I do thanks Josh.

I suspect though that initially going from OS 10.6 to OS 10.7 might possibly entail a bit more than a "small" delta.

As Glenn also points out, multiply that by a few machines and all of a sudden that's six months worth of capped data gone.

Cheers, Gobit
Glenn Fleishman  An apple icon for a TidBITS Staffer 2011-06-06 19:59
10.7 will be a full installer, too, not a delta. So it'll be a good 5 GB, if not more.
Troy Payne  2011-06-06 16:55
Any word on whether any of the iCloud stuff is manageable via Lion Server?

I know I can set up a SL Server to have a software update service, so that I only have to download those once for all the Macs on my network. Any chance a similar thing could be in the works for iCloud?
Anne Walk  2011-06-06 18:26
Hopefully, we'll get some idea of the numbers before installing Lion and OS5. Our internet provider has instituted caps recently although we haven't received any notices yet and we have 12 internet capable devices in the house.
Regarding multiple downloads of patches, deltas, etc... Presumably the Support > Downloads page(s) won't be going away? I might have missed such an announcement, but I don't think so.

If you have multiple devices, download whatever updater you require centrally and then share it locally. Just like we do just now, and have done so for years...
rodney  2011-06-13 16:54
"Each computer has to download the installer separately, according to reports; the installer is deleted after installation, requiring a new retrieval for each machine!"

This is completely nuts. OS upgrades are bad enough as bandwidth leaches go, but to require users to download a complete OS for each install is crazy. What will the approach be for those of us with multiple machines?
Mark Nagata  2011-06-13 19:05
The link in the "Synchronization and Backup" section is wrong. The correct page is apps-books-backup.html (no 'documents') and the page header is ""Apps, Books, and Backup" (no "Documents").
Glenn Fleishman  An apple icon for a TidBITS Staffer 2011-06-13 21:48
Apple changed this link in the last few days and split Documents into a separate page. Thanks for noticing. I've corrected the text and link.
Hart Bezner  2011-06-13 21:25
Oh dear, oh dear - someone else misuses the technical term "bandwidth" while referring to data caps. Bandwidth refers to the data rate over a link and is expressed in bits/second.

Some people enjoy a bandwidth of 10Mb/s and others dream of 100MB/s. High bandwidth is dangerous because it makes it possible to download huge volumes of data very quickly, potentially exceeding your data cap.
Glenn Fleishman  An apple icon for a TidBITS Staffer 2011-06-13 21:48
These are commonly referred to as "bandwidth caps" by the regulators, industry, and technical press, even if one should call them "usage" caps. I've fixed our errant usage for clarity. (Pedantry in comments is another matter.)
Patrick McClure  2011-06-14 01:53
Something else just crossed my mind: what happens to web hosting with the advent of iCloud?