How Carriers Hamstring Your Smart Phone (and 3G Modem)

[ginggs]

Interesting article:
http://www.technologyreview.com/communications/38435/page1/

One of the first things the researchers discovered was the apparent handicap on network speed imposed by a major U.S. carrier. (For legal reasons, the team anonymized its data.) Surprisingly, packets of data sent across this network are buffered by the carrier itself. This means that when a packet of data fails to make it to its destination—a common occurrence on noisy wireless networks—it cannot be instantly retransmitted, as it would normally be on the Internet. Instead, the sending device must wait a long time—on the order of seconds—for a time-out to alert it to the failure.

Other carriers, all of them outside the U.S., proved to have significant security vulnerabilities in their networks. The most insecure network allowed "IP spoofing," in which an attacker disguises his own device's network address as the address of another device. This allows the attacker to both send illicit data to a user's mobile device and to download data under that IP address.

A second, less severe vulnerability on some networks allows malicious websites to entrap users. Normally, a user can simply close a browser that appears to have landed on a piece of malware, but in some networks a time lag between when a TCP connection is closed on a device (instantly) and on the network (a delay of 20 to 30 seconds) could allow an attacker to keep that connection open indefinitely. This could enable battery-draining attacks in which, for example, a hacker continually streams data to a device.

Eleven of the carriers tested had implemented policies that could drain the batteries of a user's phone up to 10 percent faster than usual. Many devices must keep TCP (network) connections open for long periods of time to make e-mail and other "push notifications" work. Mobile ISPs that time out these connections too quickly—say, every 10 minutes versus every half-hour—force devices to power up their radios more often, to reestablish a connection.

Edit: The above would also apply to everyone using a 3G modem on their laptop/desktop. How well would the South African network operators compare?