Customers of AT&T's mobile phone service can attach outside devices and run outside applications, the company has said, following an announcement last week that Verizon Wireless would open up its network.

But AT&T's GSM-based network has been open to outside devices and applications for years, the company said. AT&T will start to publicise that information through sales staff at AT&T stores, Ralph de la Vega, CEO of the company's wireless business, told USA Today.

"By its nature, GSM technology is open," said Michael Coe, an AT&T spokesman. "Customers could always use GSM phones not sold by AT&T on our network. We can't guarantee the performance of the device, of course."

AT&T's customers can also take their handsets to other mobile service providers using GSM, with one major exception: Apple's iPhone. AT&T will not unlock the iPhone to use on other networks, Coe said.

For other devices, "we will unlock the device when customers fulfill their contract; we will also unlock the device if the customer pays full price for the device," he said. "The iPhone, however, is an exception. The iPhone is exclusive to AT&T in the US."

AT&T's publicity on its open-access policies comes after competitor Verizon Wireless announced on 27 November it would open its wireless network to outside devices and applications by late 2008. Devices will need to be tested by Verizon before they can be activated, the company said.

The Verizon announcement came after Google launched the Open Handset Alliance, an open-development platform for mobile phones, earlier in November.

The actions of Google and Verizon didn't prompt any changes at AT&T, Coe said. "First, we did not make an announcement," he said. "Second, it's always been this way."

Customers who want to bring a GSM device to the AT&T network can purchase a SIM card through the company, Coe said. If the device operates in US spectrum frequencies, AT&T will activate the device, he said.

Outside applications

AT&T also allows outside applications on its network, Coe said. "People have access to a vast array of applications today, some that are provided through AT&T, others that are not," he said in an email. "We take an open approach to music, wireless operating systems, email platforms, etc. We actively encourage developers to create applications and 20,000 have registered on our developer's site."

Art Brodsky, a spokesman for open-access advocate Public Knowledge, said he was taking a wait-and-see approach to the AT&T open-access policy. "So far, we only have one quote from one company executive," he said. "The theme is fine, and we approve, but would like to see more details."

But Mary Greczyn, spokeswoman for startup Frontline Wireless, called the AT&T position on open access "a huge win from a policy standpoint".

Frontline, Public Knowledge, and other groups successfully pushed for open-access requirements on the part of the 700MHz spectrum band, to be auctioned by the US Federal Communications Commission starting in January. AT&T's move is a "reaction to what Frontline had proposed as open access in the first place," Greczyn said.

Despite open-access policies from Verizon and AT&T, Frontline believes US residents will need more competition among broadband carriers, and Frontline intends to bid on the 700MHz spectrum in order to build a wireless broadband network, Greczyn said.