Image caption The Communications Data Bill was dropped after opposition from the Lib Dems

Fresh proposals to investigate crime in cyberspace are being promised, after the so-called "snoopers' charter" was dropped from the Queen's Speech.

The measures to be brought forward would help protect "the public and the investigation of crime in cyberspace".

The main plan is to find a way to more closely match internet protocol (IP) addresses to individuals, to identify who has sent an email or made a call.

The Communications Data Bill was dropped after opposition from Lib Dems.

That bill, which proposed internet companies be obliged to store for a year details of all Britons' online activity, was blocked by Deputy Prime Minister Nick Clegg, who said it went too far.

The Home Office has, however, said action is needed to reflect the fact criminals are increasingly using internet phone calls, or social-media sites to communicate.

Instant messaging

In the briefing notes on the Queen's Speech, the government makes clear it remains "committed to ensuring that law enforcement and intelligence agencies have the powers they need to protect the public and ensure national security".

Analysis With the Data Communications Bill kicked into the long grass there remains the vexing question of the £405m the government has spent since May 2010 on what is known as the Communications Capabilities Development Project. The Home Office insists that this money is unrelated to the unsuccessful and heavily criticised bill, saying instead it has gone on "sustaining and enhancing existing capabilities". A written response to questions posed by Conservative David Davis revealed that £50m went on consultants, but the government said it couldn't go into more detail without "compromising national security". What it does reveal, though, is the government's determination to increase surveillance powers to take account of new technologies such as social media, web mail and internet phone calls. The "snooper's charter" may be dead but the problem of how to access data in the digital age has gone nowhere. Digital forensics expert Prof Peter Sommer is in no doubt there will be a successor to the snooper's charter but he thinks that the next incarnation of the bill may be a more targeted one - with the government asking firms such as Facebook and Google to preserve data of "people of interest to the police" rather than that of the whole population. What he and others hope is that next time around there is more consultation with industry to ensure that any new bill is workable and fair.

"These agencies use communications data - the who, when, where and how of a communication, but not its content - to investigate and prosecute serious crime," it says.

"Communications data helps to keep the public safe - it is used by the police to investigate crimes, bring offenders to justice and to save lives.

"This is not about indiscriminately accessing internet data of innocent members of the public."

The proposals to be brought forward would address the fact the police - who can already tell when, where and who made a mobile phone call or sent a text message - cannot always trace the origin of an email, a message sent via instant messaging or a phone call made over the internet.

The government says one of the problems is IP addresses are shared between a number of people, or devices.

"In order to know who has actually sent an email or made a Skype call the police need to know who has used a certain IP address at a given point in time," it says.

They government says it is "looking at ways of addressing this issue... it may involve legislation".

International action

There have been questions raised about how, or whether, it might be possible to achieve the goal of matching IP addresses more closely to devices or individuals.

"The problem stems from the way that the fixed internet has been designed," said Prof Rahim Tafazolli, director of Surrey University's Centre for Communications Systems Research.

"Many people can share a single IP address and the IP address may be dynamic - meaning there's a new address issued each time they log on - while a communication traverses across different networks. It can be difficult to link all these addresses and trace them back to the origin.

"One possible solution would be to find a way to associate a person's internet use with a fixed and unique number such as their mobile number or a device's MAC [media access control] address.

"But that would require changes in the way addresses are allocated on the internet and changes would need to be adopted internationally because we couldn't just change it in the UK."