Mobile networks are incapable of carrying out the massively increased internet surveillance being demanded by intelligence and law enforcement agencies, MPs and peers heard today, raising further doubts over the technical feasibility of the plans.
Major technical upgrades would be required for mobile broadband providers to even keep basic records of websites visited, said T-Mobile data protection chief Martin Hoskins.
"We've got no legitimate business reason to do that, so we don't," he told the All Party Parliamentary Group on Privacy, which is investigating the government's Interception Modernisation Programme (IMP).
Hoskins explained that mobile broadband uses very few IP addresses to serve many customers, so associating web activity with individuals, as demanded by IMP, is not currently possible. He said T-Mobile's network can serve over 1,000 customers via a single IP address.
Informed sources reported similar figures for rival operators.
Under IMP, however, officials do not just want network operators to collect and store basic communications data. They want to install equipment to allow access to details of who contacts whom, when, where and how via third party communications services, such as Facebook and webmail.
In his evidence, Hoskins echoed the concerns of fixed-line ISPs - reported here - that the technology to carry out such data harvesting does not exist.
"Somehow we would be required to open up proprietory communications protocols," he said. "We're not sure that can be done."
Tim Hayward, the Home Office's director of IMP, said in his evidence that officials are working on the assumption the necessary advances in deep packet inspection (DPI) technology will arrive in "five to 10 years".
"[Today] we have the basis of that technology," he said. "[It] will do some of what we need."
The Group chairman, Conservative Edward Garnier QC, briefly touched on the £2bn estimate the Home Office says it will cost taxpayers to store communications data under IMP over ten years. Hayward said the figure was not a budget and did not offer details of how it was arrived at.
He was joined in support for the government position by Jim Gamble, the CEO of the Child Exploitation and Online Protection Centre (CEOP). In a typically forthright presentation, he said communications data was an essential tool in virtually all CEOP investigations and insisted IMP would "maintain capability" to access it.
Asked by Conservative peer the Earl of Northesk whether there was a danger of function creep inherent in IMP, as observed in the use of surveillance powers by local authorities, Gamble said: "I don't see any evidence of that."
Gamble's intervention was queried in evidence given by Dr Richard Clayton, a Cambridge University security researcher. He said to collect third party communications data from inside traffic streams, DPI equipment would have to be configured often, and remotely. For example, the way email addresses are contained in Hotmail traffic has changed several times, Clayton said.
IMP's surveillance equipment would have to keep up, MPs and peers were told. Such technical work will be done in secret, by "chaps in Cheltenham", Clayton said, suggesting IMP is driven by national security concerns rather than law enforcement agencies such as CEOP.
As we've reported, Cheltenham's GCHQ eavesdropping station is already gearing up to provide such capabilities, under its classified "Mastering the Internet" project. ®