iPhone, Mac, Touch users at Princeton plagued by flakey Wi-Fi connections

[This is an UPDATED version of a news story posted elsewhere on our Web site] Princeton University iPhone and iPod Touch users, as well as Macintosh PCs, are being plagued with Wi-Fi connectivity issues on the campus network, according to a story this week in the “Daily Princetonian,” the independent student newspaper. The problems, affecting “many students,” began last September, and there’s been a “large increase” in failed or flakey connections since then, apparently due to the way some applications make use of the network. According to a Web posting http://www.net.princeton.edu/multi-dhcp-one-interface-handling.html from Princeton’s Office of Information Technology (OIT), the problem is caused by devices that end up running multiple Dynamic Host Configuration Protocol (DHCP) client on a single network interface at the same time. As a result, the device can end up using several IP addresses that DHCP has assigned to other devices, disrupting their access to various network services, including the campus wireless LAN. This type of incident can and does involve any kind of client, not just Apple devices, and OIT reports that it routinely saw a “small number of incidents of this nature each year.” But starting in September 2008, there was a “large increase” in these incidents, involving Apple devices: iPhones, iPod Touches, and Macintosh computers. There’s been no corresponding jump with other devices malfunctioning this way, though those incidents do still occur. The other difference is that with other devices, OIT has been able in nearly every case to identify a misconfiguration that’s caused the DHCP malfunction. That’s not the case with the Apple products. “We do not know why so many [Apple products] have malfunctioned in this way…. Perhaps at or shortly before that time, some bug was introduced in the operating systems that run on these devices. Or perhaps some applications become available that trigger the malfunction,” according to the OIT Website. According to the Daily Princetonian story, the culprits are applications that tend to “connect and disconnect to the [wireless] network briefly and repeatedly.” One comment posted to the Princetonian story, apparently a recent computer science alumni, noted that the “persistent reconnecting to the network sends unnecessary broadcast traffic (in the forms of DHCPDISCOVER traffic) across the network, and needlessly usurps IP leases from the DHCP pool that could otherwise be used to provide service to other devices.” Princeton and Apple have not yet responded to a recent request for information on the issue. One offending application mentioned on the story is Remote http://www.apple.com/itunes/remote/, a free program introduced by Apple last year, which uses a Wi-Fi connection to let the iPhone or iPod Touch remotely control Apple TV or iTunes running on a computer. There’s a lengthy and lengthening discussion thread on the Apple support Website, with complaints about a wide range of iPhone Wi-Fi connectivity issues, for both the 3G and original devices. http://discussions.apple.com/thread.jspa?threadID=1680864&tstart=0 Users report struggling a variety of suspected causes, but no consistent pattern or cause. In some case, the Wi-Fi connectivity started working again as mysteriously as it had stopped working.