Schools fear new encryption will cripple safety filters

PLANS by Google and Mozilla to encrypt web browsers risk creating a ‘free for all’ of children visiting harmful websites at school, experts warn.

The new technology threatens to cripple filtering software used by schools to block dangerous websites and flag when children are accessing harmful material.

The threat has prompted the body that represents head teachers to warn the tech giants not to ‘hamper schools efforts to keep children safe’. The Government is also looking at the encryption plans to ensure they do not have ‘unintended consequences’ for schools.

Since 2015 schools have had a legal obligation to block websites hosting material such as terrorist content or child abuse. Most schools employ sophisticated filtering systems that bar access to a host of other sites, from pornography and gambling to those glorifying self-harm and suicide.

However, the tech giants are developing a technology, called ‘Encrypted Client Hello’ (ECH), for their web browsers to hide what users are viewing from outside organisations.

Software engineers said ECH would disguise the addresses of harmful websites from their programmes, hindering their ability to spot harmful websites.

Steve Hill, technical director at Opendium, which provides filtering software to schools, said: “We don’t have a way to deal with it (ECH) so schools would not really be able to provide a safe network. It would turn into a free-for-all.”

“The problems we are having are across the industry, so providers supplying to schools are being hit by the same issues.” Mr Hill’s concern’s were backed by David Wright, of the UK Safer Internet Centre, who said: “I get the points about (ECH strengthening) privacy, but what if we miss harm to a child? For me, that is paramount.”

Mozilla, which owns the popular Firefox browser, has stated its plans to roll out ECH, saying it is “eager for users to realise the privacy benefits”. Google is building a prototype of ECH for its Chrome browser. Both companies declined to speak about their plans.

Google sources said the company had not announced plans to roll it out and that schools would be able to configure any new Chrome feature to work with their systems.

The issue with ECH stems from the fact it will only allow filtering systems to see the ‘IP addresses’ of websites users are visiting rather than the individual sites. IP addresses are broad online locations shared by many different websites.

Experts said the change would mean school filters would have to blot out large swathes on the internet for pupils or risk allowing access to harmful websites.