A petition signed by more than 110,000 people demanding internet service providers block pornography by default is being handed to the UK government today, as consultation on the topic draws to a close.

MP Claire Perry
MP Claire Perry delivered a petition of 110,000 signatures supporting the opt-in system to Number 10

Proposals for a system where internet users would have to opt-in to viewing adult content is supported by several MPs, but strongly opposed by internet rights campaigners and service providers, who say an "active choice" system is the best solution.

Active choice systems have already been implemented by some ISPs and involve asking the customer if they would like to filter adult content when they first sign up to the service, but critics say the vast number of users who are already online are not given this option.

The petition will be delivered to 10 Downing Street on 6 September and is backed by Conservative MP Claire Perry; findings of the consultation, which finished on the same day, are due to be published later this year.

Perry told the BBC: "The petition suggests a high level of support for the opt-in idea. We quite happily accept watersheds on TV and we are happy to accept adult films sitting behind PIN systems on satellite channels.

"Somehow when it comes to the internet, all bets are off and the onus is entirely on the consumer. This has been an area where there has been relatively large corporate interests in not filtering, and rather intimidated consumers who are made to feel they should back off."

Opponents to the opt-in system include investor of the world wide web, Sir Tim Berners-Lee, who said: "My personal preference has always been that if you want to block sites, you download software, and you install it for your children, rather than having the ISPs involved.

"The job of the ISPs is to provide good internet connectivity, not to spy and not to block."

In a joint letter to the Prime Minister rights groups including Big Brother Watch, the Open Rights Group and Index on Censorship, said: "Blocking is trivial to circumvent and it is likely a default blocking system would lull parents into a false sense of security."

The petition has, however, been criticised by campaigners for citing surveys with small and unreliable sample sizes. One example is a statistic claiming one in three under-10s has been exposed to porngraphy online and taken from a 2010 issue of Psychologies magazine.

The survey was criticised because it asked a group of 14-16 old years and just one school in London if they had seen porn before the age of ten; Perry passed the survey off as "a small scale anecdotal study."

BT and Virgin Media have both said that they would back active choice over the opt-in system.