The US Drug Enforcement Administration (DEA) is warning agents over security components in Apple's iMessages which may make government eavesdropping all but impossible on the platform.
According to an internal document obtained by the media, the DEA has warned agents that intercepting and decoding many messages over the service is not possible due to the way iMessages handles connections between iOS devices.
Rather than relying on SMS technology to send messages, iMessages uses a WiFi or broadband internet connection to transmit message data.
In addition to keeping bills for SMS messages down, the feature has security benefits. As a secured internet transmission, data packets are encrypted and thus would be highly difficult for a third party to decode even if the packets themselves could be captured.
In a memo posted by CNET, the DEA said that such connections would be 'impossible to intercept' for intelligence purposes.
"The significance of the iMessages transmission is that investigators may erroneously believe they have a complete record of text transmissions if they are unaware that iMessages communications between smartphones are not captured or provided by the cell phone service providers," the note read.
The DEA memo went on note that while communications between iOS devices are secured, messages to other platforms or devices without a wireless internet connection would still be sent under conventional SMS protocol.
But Julian Sanchez, a senior researcher at think tank The Cato Institute, poured scorn on the reports.
"The article strongly implies that this means encrypted iMessages cannot be accessed by law enforcement at all. That is almost certainly false," he wrote on a company blog.
Apple keeps a copy of the encryption key, said Sanchez, which enables users to reset their password via a browser, and restore content on to a new device.
Most mobile operators only keep SMS messages for a matter of days, unlike Apple which keeps iMessage content indefinitely.
"That means cops should be absolutely overjoyed if drug dealers or other criminals start using iMessage instead of SMS," he added.
Encryption technology has long been a contentious area for governments. Throughout the Cold War, the US government placed strict controls on how encryption technology could be exported, classifying encryption platforms alongside munitions and other restricted items.
More recently, firms such as BlackBerry have run into trouble with governments around the world for the encryption technology used in their communications platforms.
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