iPhone Mystery at Duke University: The Case of the Flooded Routers

A handful of Apple's (AAPL) iPhones have managed to knock out large sections of the campus Wi-Fi network at Duke University, and network officials there still don't know why.

John Cox at NetworkWorld.com reports that on two occasions, once last Friday and again yesterday, several iPhones -- perhaps as few as two -- flooded  campus routers with IP address requests, overwhelming up to 30 of them at once and putting them out of commission for 10 to 15 minutes.

“Because of the time of year for us, it’s not a severe problem,” Kevin Miller of Duke’s Office of Information Technology told NetworkWorld. “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?"

There are already 150 iPhones registered at Duke, which during the school year hosts nearly 13,000 students. Dozens of Wi-Fi hotspots are scattered around the three main campuses -- West, East and Central -- in Durham, N.C.

When Wi-Fi access points began issuing the equivalent of busy signals, Duke network staff traced the problem to misbehaving iPhones that were flooding the routers with bogus Internet address requests -- at the rate of up to 18,000 per second.

Miller is not sure what's going on, but suspects the problem may stem from the overly aggressive way the iPhone deals with dropped Wi-Fi signals. “It may have something to do with the iPhone losing connectivity and then trying to reconnect in a new location,” Miller says.

Most of the university Wi-Fi network runs on Cisco routers, but Miller says he doesn't believe the problem is connected to Cisco "in any way, shape or form."

Communications with Apple so far has been, in Miller's words, "one way." The Duke team opened an Apple problem ticket , which has since been "escalated." But as of Monday afternoon, nothing substantive had been heard from Cupertino.

The real mystery may be why this problem, if it is Apple's, hasn't surfaced anywhere else.

Comments

[Tom B]

Probably the POS Cisco routers, but, given that Cisco equipment is widely used, I hope a fix comes soon. Maybe it's a system config problem on Duke's end, given that I haven't heard other reports?

[Apple Tech support]

Answer 1: This is the first time I've heard of this, let me elevate this and see if anyone has come across this problem before. Even better would be if there were a solution to your problem. [followup call a day later: we're still working on your problem. It sounds serious, but we haven't come across it before. We have elevated it to the highest levels. Someone from the troubleshooting will be contacting you for more details. Can you consistently reproduce the problem? No, it's sporadic? That makes troubleshooting difficult, but we'll work on it to help you discover the source of the problem.]

Answer 2: Did you reboot the router? Did you turn off the iPhone?

Answer 3: Oh, this problem happens all the time. Yes, I've seen it before for months now. Just download the new firmware for your router and it will fit it. Call us back if that doesn't work.

Answer 4: I've never heard of this before, but I know exactly what the problem is. I've been working at this level 1 desk for 2 months, and I can tell you the solution right now. I'm the only person here that can read minds, troubleshoot any problem and (click - ATT wireless connection dropped.).

[Aiyo]

Aiya, a few students are on the backseats of scooters using i-phones and wi-fiing when going around the campus lah.

[Jim]

>>>several iPhones -- perhaps as few as two -- flooded campus routers with IP address requests, at the rate of up to 18,000 per second<<<

I've been working as a Cisco Engineer for a long time and never have I heard anything like this!

First of all, Cisco wireless access points/routers can't handle 18,000 requests a second.

Second of all, iPhones must be using some powerful processors to be requesting DHCP address 9,000 times a second.

I'd have to point to a buggy Cisco IOS Software.

[Matt]

" ... Miller says he doesn't believe the problem is connected to Cisco "in any way, shape or form."

It is no doubt a Cisco/Duke config issue. It would be happening universally if iPhones were the issue. Go back to Trouble Shooting 101 and quit kissing-up to Cisco.

[Donovan]

What about iPhone users outside Duke?

Maybe its the surrounding users pillaging the university wifi in the vicinity: 2 golf clubs, medical center, residentials, off-campus housing, Durham has a populace over 200,000.

[DC]

If communication has been one-way, why does the article say the ticket has been escalated? That would require a response on Apple's part. Doesn't sound one-way. Sounds like they're being sensitive to the issue. An issue that's connected to Cisco, not them.

[socrates]

wow that's a really powerful phone, and omfg I had no idea cisco routers could handle such requests....what? oh, niether can do those things?

it seems that in this time of software / hardware / wifi blah blah blah it is commonplace for a new product to come out with "needed fixes", could you imagine if the same were true in the medical equipment field?

sounds like another case of Apple hate, once again Apple has produced a gadget that actually does what they said it would do, right out of the box, hmmm you mean tech stuff CAN be built right the first time? go figure, and then go buy apple stock.

[TX]

Has anyone considered some Duke kids are too smart for their own good, hacked their phones and made an algorithm that would.. well... do exactly what it did? Sure its summer now, but this could get interesting around registration or exam times...

[plato]

It's Nifong's fault.

[Matt Blasi]

It is always fun to read when a person makes a huge long post and is completely off base.

I am glad to see though that many commenter's have already pointed out the same things I would have.

To add another bit of logic to the pond, if the iPhone could and was making that many requests, shouldn't you be asking (since you all set them up on your network) Why are they dropping connection in the first place when you have so many access points (300 routers) around to support the 13000 students of which what 5000 maybe are there now in the summer season?

To me it goes to show that the IT and Networking department of the Campus must not be looking to their own instructors and graduates for hiring. I would like to know what troubleshooting you have done to come to the complete solution that it was "as few as two" iPhones.

Quote:
"Has anyone considered some Duke kids are too smart for their own good, hacked their phones and made an algorithm that would.. well... do exactly what it did? Sure its summer now, but this could get interesting around registration or exam times..."

It was a beta test, now that they know it works with 2 wait till they have all their friends back at school and 20 of them are on campus... hehehe.....

=)

[Jon Ostrega]

I plan on starting an online petition to have this blog shut down (or at least removed from money.cnn.com).

I have no doubt that I will have an easy time finding supporters.

[cmak]

Who turned off the Spanning Tree Protocol on the servers?

Oops...

ex ped: Good question! Forwarding to Duke IT... --Philip Elmer-DeWitt

[sean]

please stop this my apple shares dont like it

[robert abooee]

So, what your saying is that Cisco routers see an iphone and are generating the requests themselves? Talk about having their head up a companys ass? Um...Apples stuff works out of the box? They come out with a new "Animal" every year. They just dont call the new software "a patch"

[Paul]

Network works fine, then iPhones come along and bam the network goes crashing down. Hmm, why can't iPhones place nicely?

[rilrem]

I just wanted to say that although all of you think you are better and smarter than the geniuses working in the Duke IT department, you might actually consider that those people, who have set up one of the most reliable and expansive networks on an American university campus, actually know what they are talking about. Perhaps the person with their head up a "company's ass" are the people who are defending Apple though their products HAVEN'T always worked right out of the box and their engineer's HAVEN'T even responded to the issue.

[MacBigot]

Let me see if I can wrap my head around this -- some bored students figured out what the MAC address range is on the iPhones, and they styled an attack using a couple of Linux machines hidden somewhere on campus to masquerade as Apple 'troublemakers', and are sniggering at the resulting buffoonery created between the Duke 'network admins' and the press.

Hello!?!??!? If these are actually the people responsible for Duke's network, they would have better communication skills -- what they are saying is happening is less unlikely than impossible (unless the iPhone and Cisco's routers' SuperPowers are being boosted by the Earth's yellow sun and are no longer hindered by their original design limitations).

Why has this been going on for several days and yet no one has reported the same issue on another network?

It's because: It's not happening on Duke's network, either. It's a hack. A scam. A ruse.

By some students who can probably be identified by a duct-taped WiFi canon made from a couple of Pringles cans protruding from their backpacks.

The 'reporter' should be ashamed for not doing his homework.

[Michael]

To those that claim the iPhone works right out of the box, perhaps you should have read the link at the top of the page.

http://blogs.business2.com/apple/2007/07/sixty-eight-cou.html

Sounds like it has a ton of problems to me.

[Jim]

Here is a new link from Yahoo pointing the finger on Cisco.

http://biz.yahoo.com/ap/070720/iphone_duke.html?.v=3

I'm sure Business 2.0, ElmerFud-DimWitt will not write a story on clearing iPhone from causing the issue in the first place.

ElmerFud-DimWitt should be fired from Business 2.0.

ex ped: Posted. Thanks for the tip. --Philip Elmer-DeWitt

[JBDavis]

Interesting......I don't have a vast Duke U network but a wireless router (netgear) home network. By the process in elimination on a resent "dropping" problem I have found that my iphone is suspect. It can even change the ID to "Apple Network" and make all other devices unable to connect. Interesting indeed.