Princeton University Identifies iPad DHCP Flaw
Princeton University's Office of Information Technology has posted a document describing networking problems suffered by roughly half of the 40 iPads on campus. The problem isn't so much experienced by the iPad as caused by it - here's what's happening.
The iPad uses DHCP (Dynamic Host Configuration Protocol) client software (in the iPhone OS) to request network configuration information - most notably an IP address - from a DHCP server. That IP address is typically "leased" to the DHCP client for a period of time; once that lease expires, if the DHCP client is still online, it asks to renew the lease and retain its IP address. If the client is not online when the lease expires, the DHCP server is free to assign that IP address to another device. When the DHCP client returns to the network, it requests and receives a new IP address.
The problem seems to be that the iPad, in some situations, is failing to renew its DHCP lease but continuing to use the previously assigned IP address. Because the lease wasn't renewed, the DHCP server believes it is free to reassign the IP address. If that IP address is reassigned to another device while the iPad continues to use it, both devices end up using the same IP address, which can cause loss of network connectivity, confusing dialogs as operating systems attempt to handle the error condition, and more.
Princeton is working with Apple to resolve the problem, which is believed to lie with the DHCP client in iPhone OS 3.2, and which should be easy to fix with an update to iPhone OS 3.2. In the meantime, Princeton recommends that iPad users not connect to the campus network because if the iPad malfunctions, they may need to be blocked to prevent them from causing problems for other network users.
Who's likely to experience this problem? Primarily institutions with large networks that rely on DHCP for a constantly changing collection of network devices. Home users and those with small networks aren't nearly as likely to experience IP address collisions due to this problem.
If you do run into this problem on a small network you control, there are a variety of possible solutions:
- Assign a static IP address to your iPad and configure your DHCP server to avoid handing out that address to other devices. This fix isn't feasible on a large network with a lot of devices because it requires too much manual intervention.
- Configure your DHCP server to reserve a particular IP address for your iPad. I tried this in AirPort Utility using the client ID approach to identifying the iPad, but it didn't work; it's possible the MAC address approach would work better. This approach also requires too much manual intervention to be useful on a larger network.
- Set a very long DHCP lease time so the DHCP server is much less likely to reassign the iPad's IP address to another device. Trying this on a larger network would likely tie up too many IP addresses that weren't actually in use or require the use of NAT.
It is worth noting that, despite a quote in The Daily Princetonian article linked above, this DHCP problem is almost certainly unrelated to the Wi-Fi problems that have plagued some iPad users (see "Some iPad Users Suffer Wi-Fi Woes," 6 April 2010).
Nevertheless, here's hoping that Apple fixes this problem soon, not because it's necessarily causing all that much trouble even for large networks, but because it would be a shame if the iPad garnered a bad reputation among network managers based on what should be an easily fixed bug, given that DHCP is a long-established standard.
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iAds could make a billion dollars, help Google make their deal
Filed under: Apple
There's not a lot of details out about Apple's upcoming mobile advertising program, iAds, quite yet, but Broadpoint Amtech is already convinced it's a moneymaker. Analysts there say that the program could generate a whopping US$4.67 billion in revenue in just one year's time. Of course, that's a high-end guess, but even the medium figures are pretty amazing -- analyst Brian Marshall suggests that even conservatively, Apple could earn $2.48 billion. Realize what we're talking about here: this is more or less a from-scratch profit stream for Apple, and with developers receiving 60% of the revenue from iAds, Apple won't be the only company making money.
In fact, Apple's good news may benefit Google, too -- CEO Eric Schmidt said that Apple's iAds announcement should convince those concerned that Google's deal with AdMob is good to go, and that the two companies will just be one big player in "a highly competitive market." Of course, Google has a bit more advertising experience than Apple -- it made most of its $23.7 billion revenue last year from its online advertising model. While iAds sounds big, it's not quite that big.
Still, iAds will be big, and there's room to grow -- Apple is starting off with the mobile market, but don't forget that they've got a whole library of iTunes podcasts, and content space on AppleTV to sell as well. At this time next year, we might be reporting that Apple really has created a $2.5 billion-per-year income stream for themselves.
iAds could make a billion dollars, help Google make their deal originally appeared on The Unofficial Apple Weblog (TUAW) on Mon, 12 Apr 2010 15:30:00 EST. Please see our terms for use of feeds.
iAds could make a billion dollars, help Google make their deal originally appeared on The Unofficial Apple Weblog (TUAW) on Mon, 12 Apr 2010 15:30:00 EST. Please see our terms for use of feeds.
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Palm puts itself up for sale
Filed under: Apple
Well, after the abysmal Pre sales, who didn't see this coming? Palm has put itself up for sale. Bloomberg reports that, at this point, Taiwan's HTC Corp. and China's Lenovo Group Ltd. have expressed interest in the company and may make offers. However, the most likely buyer of Palm is expected to be HTC. Though HTC has committed to the Android platform, Palm has something they desperately need: patents.
In March Apple filed suit against HTC for infringing on 20 patents concerning the iPhone's user interface and hardware. If HTC could acquire Palm's patents they would have ammunition to use against Apple, which would open up the possibility of a counter-suit. As of market close on Friday, Palm was worth only $870M, making it a relatively cheap company to buy.
So cheap, in fact, that it would make sense for Apple to snap the company up -- again, just for the patents. An Apple acquisition of Palm would not only prevent HTC from acquiring the ability to counter-sue Apple, it would strengthen Apple's patent portfolio even more and leverage greater protection against its intellectual property.
[via 9to5]
Palm puts itself up for sale originally appeared on The Unofficial Apple Weblog (TUAW) on Mon, 12 Apr 2010 09:00:00 EST. Please see our terms for use of feeds.
Palm puts itself up for sale originally appeared on The Unofficial Apple Weblog (TUAW) on Mon, 12 Apr 2010 09:00:00 EST. Please see our terms for use of feeds.
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Rumor: Apple buys Intrinsity
Filed under: Apple
We've heard a few times now that Apple was ready to pick up some smaller, innovative hardware companies, and the rumor mill now says that chipmaker Intrinsity was purchased by Apple late last week. Rumors first hit on April 1st about the company being sold to a bigger buyer, and on Friday at least one employee was saying the buyer was in fact Apple. There's still no official word of a sale, as far as we can tell, but maybe Apple is waiting for a certain press conference to reveal that a new company will be providing chips for future, oh I don't know, iPhones.
Intrinsity certainly fits the bill for the kind of company that Apple would want to buy with all its cash -- it's behind some of the fastest mobile processors out there, and that's certainly what Apple is looking for. It's also unencumbered by other ownership (which means Apple can pick it up outright), and it's got that nice mix of innovation and quality that Apple usually looks for.
In short, even before the event on Thursday, we can probably expect to see Intrinsity behind some of Apple's processors in the future -- if they haven't made a few already.
[via Engadget]
Rumor: Apple buys Intrinsity originally appeared on The Unofficial Apple Weblog (TUAW) on Mon, 05 Apr 2010 17:30:00 EST. Please see our terms for use of feeds.
Rumor: Apple buys Intrinsity originally appeared on The Unofficial Apple Weblog (TUAW) on Mon, 05 Apr 2010 17:30:00 EST. Please see our terms for use of feeds.
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Turn that old Mac into a functioning clock
Filed under: Hardware, Odds and ends, iMac, PowerMac G5, Mods
Let's say you have a Mac collecting dust in the corner of your garage. Rather than succumb to your spouse's demands and send the old friend to computer heaven, why not re-purpose that Mac into something both functional and beautiful?
Cult of Mac points us to one enterprising hardware modder who has converted the base of his iMac G4 into a round wall clock. Take a look above on the left for the final result of his Dremel-sourced endeavor. This Apple fan from Japan was also kind enough to post photos of his DIY adventure [Google Translate link]. Check out another image below; the aluminum really pops on the dark wall.
Additionally, it seems that the inspiration for the iClock came from another Japanese modder who converted his PowerMac G5 into a functioning timepiece as well. Seen at the top on the right is the completed product. When all is said and done, it seems as though the PowerMac is still usable as computer. This qualifies the creator's work to be considered a "case mod" rather than an all out butchering -- which is ideal because a chopped Mac is a sad Mac. The PowerClock owner also posted in-progress shots of his work [Google Translate link].
I tend to fall in the camp that favors "software" modification, believing that for any piece of computing hardware there is some flavor of Linux that can breathe in new life. Unfortunately, however, sometimes Macs and PCs alike simply bite the dust and are only good for conversion into clocks or lamps.
Turn that old Mac into a functioning clock originally appeared on The Unofficial Apple Weblog (TUAW) on Mon, 22 Feb 2010 11:30:00 EST. Please see our terms for use of feeds.
Turn that old Mac into a functioning clock originally appeared on The Unofficial Apple Weblog (TUAW) on Mon, 22 Feb 2010 11:30:00 EST. Please see our terms for use of feeds.
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