iPhones Lead to Headaches on Duke’s Wireless Network

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Date: Tuesday, July 17th, 2007, 14:25
Category: iPhone

It’s new, it’s spiffy and damn is it cool to have.

And it’s apparently brought Duke University‘s wireless LAN system to its knees.

Writing for NetworkWorld.com, author John Cox has pointed out that anywhere from a dozen to 30 wireless access points have been overwhelmed by requests from several iPhone handsets.

At this time, campus network administrators are talking with Cisco, the campus’ main WLAN provider and have opened a help desk ticket with Apple.

“Because of the time of year for us, it‚’s not a severe problem,” commented Kevin Miller, assistant director, communications infrastructure, with Duke’s Office of Information Technology. “But from late August through May, our wireless net is critical. My concern is how many students will be coming back in August with iPhones? It’s a pretty big annoyance, right now, with 20-30 access points signaling they’e down, and then coming back up a few minutes later. But in late August, this would be devastating.”

The iPhones apparently flood the access points with as many as 18,000 address requests per second, consuming almost 10 megabits per second of bandwidth and overtaking the access point to the point that the access point shows up as “out of service” for up to 10 to 15 minutes at a time. During these periods, there’s no way to communicate with them.

In addition to temporarily shutting the access points down, the iPhone, through the use of the Address Resolution Protocol, will request the MAC address of a destination node since the device has already obtained an Internet Protocol address. If the device receives no answer regarding the MAC address, it just keeps asking.

Miller has stated that Duke’s network team began capturing wireless traffic for analysis and discovered that the offending devices were iPhones. There are currently about 150 iPhones registered to use Duke’s campus WLAN.

“I’m not exactly sure where the ‘bad’ router address is coming from,” Miller says. One possibility: each offending iPhone may have been first connected to a home wireless router or gateway, and it may automatically and repeatedly be trying to reconnect to it again when something happens to the iPhone’s initial connection on the Duke WLAN.

They’re still sorting out what that “something” is. On two occasions, one last Friday and one today, Monday 16 July, both users seemed to be behaving completely normally, yet both iPhones started flooding the net with ARP requests. In both cases, the user first successfully connected to the WLAN at one location, and then moved to another building, where the ARP flood began. “It may have something to do with the iPhone losing connectivity and then trying to reconnect in a new location,” said Miller.

Duke has currently commented that the trouble ticket with Apple was “escalated”, but as of now, nothing substantive has been heard from the company.

This fall could prove interesting, especially if you’re in a campus network capacity.

If you’ve seen anything along these lines or have your own stories, ideas or feedback, let us know over in the forums.

Security Firm Expresses Concerns Over iPhone Browser Dialer

Posted by:
Date: Tuesday, July 17th, 2007, 08:04
Category: iPhone

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Security firm SPI Labs claims to have discovered a threat to the iPhone’s security via the handset’s built-in MobileSafari browser. The company claims that the browser, which features an ability to dial phone numbers found on web sites, can be exploited in the following ways:
-Redirecting a call to a phone number other than the one seen on a given web site.
-Tracking calls to a site visitor.
-Bypassing the confirmation dialog box and forcing the call to continue.
-Preventing the phone from dialing calls altogether.
The firm has offered examples in which a user clicks on a malicious web site, then discovers they’re calling an international number and paying those rates.
According to The Unofficial Apple Weblog, SPI Labs has opted not to disclose the actual nature of the exploit and how to perform it. The company has stated that they have alerted Apple and are cooperating with the company as to how to plug these holes. SPI Labs has also commented that the feature can simply not be used if users are worried about security.
If nothing else, the first iPhone software update should prove interesting.
Let us know your comments, ideas and thoughts on this over in the forums.

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Intel Ships Core 2 Extreme X7800 Chip

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Date: Tuesday, July 17th, 2007, 08:09
Category: News

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On Monday, Intel released its new high-end mobile chip, the Core 2 Extreme X7800. The new chip, which is based on the company’s Penryn architecture, is geared towards higher end laptop users such as graphic artists and gamers.
According to Macworld News, Intel is encouraging vendors to push the chip’s performance by opening the unit’s protection locks, thereby allowing them to overclock the processor to run faster. Such a move helps users run the chips beyond their rated limits. This practice is fairly uncommon for notebook systems, which are usually geared around battery conservation.
Intel is currently selling the Core 2 Extreme X7800 processor to various vendors and has stated that the unit will reach store shelves within two weeks. The processor is rated at running at 2.6 GHz and is available for US$851.
No word has been given as to when the new processors will find their way into Apple’s MacBook or MacBook Pro series of laptops.
If you have any thoughts or ideas on this, let us know over in the forums.

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iPhone Users Reporting Mixed Brightness on Handsets

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Date: Tuesday, July 17th, 2007, 07:53
Category: iPhone

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The grass may be always greener on the other side, but iPhone users may have a genuine complaint in this situation.
According to the guys over at iPhone Atlas, readers are reporting that some iPhone screens are brighter than others when set to the full brightness setting. The dimmer screens also seem to display a grid pattern on the background that appears as a checkered pattern of horizontal and vertical lines in all applications (a picture posted on ImageShack presents the difference).
The problem seems to stem from two distinct revisions of iPhone LCD panels being used, a 5 series and a 7 series. This can be tested via the following instructions:
-Put your iPhone in field test mode by accessing the Phone application, tapping Keypad, then entering *3001#12345#* and pressing Call.
-Tap Versions
-Inspect the entry next to LCD Panel ID
-Users have reported that iPhones with LCD Panel IDs that begin with 7 exhibit this problem, while those with IDs that begin with 5 do not — though we’ve seen reports from users with 7-series screens that do not exhibit the issue.
The article also suggests that when checking whether or not your iPhone has this issue, be sure to deactivate the Auto Brightness setting in your Settings menu, then reset the iPhone by holding the Sleep/Wake button and the Home button for at least 10 seconds. The reading may be affected by ambient light and this is the best way to remove that factor.
Apple has yet to comment on this issue.
If you’ve seen this or anything similar with your iPhone, let us know over in the forums.

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