Few people would deny that the internet has brought into our homes a range of information, entertainment and business that would have been impossible a short time ago. It has also brought ugliness. This is especially true for children. If they use computers that are not under some kind of guidance, it is possible for them to access sites that could be disturbing, and that does not simply mean pornographic sites. There are sites with violence and photographs of accidents and many others that could be seen as far worse than naked human bodies. No matter what the content, most parents would agree that they would prefer that their children did not access such sites. They are deeply concerned with this issue but many do not have degrees in computer science, either. If it is difficult enough for them to use their own computers, how are they to control what their children do? There are plenty of different makes of software that parents can buy that enable them to closely monitor and protect their children from offending sites, but the first and simplest thing parents can do is set an operating system to block sites it thinks are not suitable for children. Brian Patterson is the director of a local public relations company that specialises in technology. He has thought about how to handle the internet with his children and has used basic techniques. 'I think the easiest first step a parent can take to protect their kids is to use the parental controls that come with most operating systems. Our family computer is an Apple iMac running the Leopard operating system and it allowed us to set up protected accounts for our two bigger boys - five and 10 years old,' he said. For the most part, he said, he was happy with the results. He does keep the machine in an open space at home so he can see what is going on if he wants to. Peter Heavyside is the managing director of third-i, a company specialising in network security. He said that much discussion was prompted by the infamous photographs that appeared all over the internet last year involving actor Edison Chen Koon-hei's private photos of himself and female starlets. Although some software on home computers would prevent your children from accessing such a site - by accident or design - it really needed to be dealt with at the network level if possible. If you have a system that relies solely on what the operating system does, then it will not be long before the children work out how to bypass it. 'They are often savvy enough to beat you at that level. What is really needed is a solution that is based at the network level. To do this would require an organisation with the know-how to maintain up-to-date information on where the harmful content is to be found and with the skills to co-ordinate all the internet service providers to execute the controls. The assistance of government would clearly be needed to implement such a capability to help with the investment needed to ensure the system had the appropriate checks and balances,' Mr Heavyside said. There was no question that whatever assistance came from government would have to be carefully debated. Blocking pornography sounds like a good thing to do, but how do you define it? One person's porn is another person's art. These are not straightforward questions. Perhaps the safest thing for young people is to employ what experts call a white list. When discussing content that is questionable or not wanted, computer scientists often talk about white lists and black lists. A black list is a list of all those sites we do not want access to and a white list is the exact opposite. Parents can set up white lists on their home computers, using the 'Parental Controls', that will allow children access only to sites the parent has approved. All other sites are not accessible. The list can be added to by a parent at any time. That is also the suggestion of a man who once helped to design nuclear command and control systems for the United States government. Thomas Parenty, the managing director of Parenty Consulting, a local information security company, once worked at the National Security Agency in such a capacity. When you do not want the wrong person firing a nuclear missile, you tend to be a bit paranoid when looking at protection. He was very clear about the safest thing you could do: 'If you have zero tolerance, then a white-list approach is your only option. No filtering is 100 per cent reliable. Just look at your spam filter.' Most parents will have to come to terms at some time with the fact that their children will be exposed to things that may shock or disturb them. No one wants this, but it is also a part of growing up and perhaps the best thing one can do is be prepared for a good long chat about a lot of things. If you want perfect protection, you are going to be disappointed. Part of growing up is learning to deal with things like this. The internet is not a bad place to start.