Web Filtering

[pooley]

Our county uses Surf Control to block the naughty web sites etc.

 

Unfortunalty you can still search google(and google images) and see words and thumbnails that are unsuitable.

 

I have a head teacher who is unhappy as while searching "welsh dragons cartoon pictures" in google came across some sites advertising porn/sex etc.

 

The sites were blocked but you could still see the Blurb about the sites i.e."cum here to see naked fcuk pics" etc etc.

 

Anyone use any soft that prevents sites with these words from being displayed ?

 

Or can someone recommend a Child safe search engine ?

 

Thanks

[webman]

Hi. I'd recommend setting up your own filtering proxy server. IPCop linux with Advanced Proxy Server and URL Filter addons make for a good, solid and free (open source) proxy server.

[RobC]

Below is an e-mail I received from Google which I think may help with regards to searching on Google...

 

Dear Robert,

 

Thank you for contacting us.

 

As you can imagine, filtering in an automated way is quite difficult.

It is very difficult to write a program that can catch all offensive

webpages and pictures. On the flip side, with 4 billion documents

and 1 billion images, we cannot use human editors to find offensive

content. Thus, our filter is not perfect.

 

The safest setting that Google has is "Strict filtering" which can be

turned on through our preferences page:

http://www.google.com/preferences?hl=en

If you select Strict filtering here you will get a very strict filter.

Sadly, a lot of the relevant pictures are also filtered when this is

in use, and it occasionally lessens the quality of our results.

 

While this filter is not password-protected, it is somewhat of a chore

to turn it on and off, so hopefully this will discourage deactivation

of the filter by the children.

 

Alternatively, if your school deploys a proxy on your web traffic, it

may be possible to configure your proxy to append "&safe=strict" to

all requests to images.google.com. This will cause strict safesearch

to be used regardless of the preferences page setting. Check with

your school's IT administrator to see if this is possible.

 

As for a list of Google urls, I recommend you to look at our list of

domains we offer Google in - http://www.google.com/language_tools?hl=en.

 

I would like to apprise you that Google is currently researching an

image search product that might be more suitable for schoolage

children.

 

Sincerely,

Karen Padham

Product Manager, Google.com

[Guest]

{quote] "&safe=strict"

 

Our provider uses this, which does indeed mean that changing the options via the google page have no effect. Have a word with your ISP pooley.

[ChrisH]

If you have a little linux skill then you can build yourself a good box with squid, Dansguardian and Squid Guard and maybe ClamAV as well but Ive not tested that yet. If your not too good with Linux I would recommend Censornet which is a Linux distro that is easy to install and use and will provide you with all the filtering you need.

If you want to do your own box I have some very rough notes on building a box under Debian.

[russdev]

I would like to apprise you that Google is currently researching an

image search product that might be more suitable for schoolage

children.

 

well they have been working this for nwo over year and half now....

 

Russ

[Geoff]

Dansguardian will filter out nastyness from google image search quite happily. Just include the 'googlesearch' wordlist in your blacklistedwords config file.

[pooley]

Thanks for the info guys.

 

Google strict search is a good option - but going around 100+ pc's and manually setting it up (possibly for every user) isnt really an option.

 

Never played with linux at all. :?

 

but will try and get my hands on a pc tomorrow and install linux - and learn on the fly lol.

 

Cant ask ISP as isp is county borough - admin and Curriculum sides seperate etc.

 

Schools have become a poor cousin.

 

Cheers

[MkII]

Here in Powys Pooley we also have Surf Control. Filtering is a big issue with individual schools, and a few have gone there own way using methods suggested above.

 

Powys have banned words within google searches, and enforce safesearch settings, both using Surf Control.

 

I would challenge other posters that no method is entirely safe. Indeed, we decided here in Powys that if we took on filtering locally we also take the legal responsibility. Our 'official' statement is that we do everything reasonably possible to block innapropriate content.

 

We feel the same as you pooley about our relationship with the county. But we do take our responsibility seriously and play our part in keeping the filter as good as we can.

 

You can always add on to the system with an additional level of filtering you control, like censornet. Only don't remove yourselves from the loop making the service for all schools worse.

[ChrisH]

Try Censornet first then Pooley.

[MkII]

Yeah - get the censornet CD - you'll lerve it

[pooley]

To be fair im not looking to alienate myself from county - but surfcontrol is not good enough for what the teachers want.

 

We have enforced safe search etc, and each school in the county can set their own filtering options, also bad words are filtered (so no searching for sex etc) but after a few pages in google/yahoo you get some sites come through anyway.

 

Going to have a little play with censornet.

 

Also going to try and find a way to enforce Strict filtering in google, but on a global scale.

[Geoff]

You can enforce strict search with Squidguard by rewriting the urls. I posted a ruleset a little while ago for ChrisH. I'll attempt to find it.

[ICTNUT]

I have just chucked out our ISA2000/N2H2 Filtering and replaced it with:

 

Smoothwall 2.0

Dansguardian

Clam Anti Virus

Advanced Proxy Filter

Advanced URL Filter

 

and as a result NOTHING (well almost) gets through, it has made my life SOOOOOO much easier in this area.

 

Best of all its free and only took 2-3 hours to get up and running 1 day to fully configure and 1 week of solid out of hours testing.

 

{edit}

did i mention the fully featured web frontend to the whole thing

{/edit}

[Simcfc73]

I can't recommend Smoothwall enough.

 

Once you get into Modding version 2.0 with all the addons it becomes incredibly powerful. With my smoothwall images like you mentioned are blocked with its bannedphraselist section which blocks...ermmm... phrases on the list like below.

 

,,

,<&safe=off>

 

Anyone who takes safe search or family filter off cannot do a search using google or altavista.

 

I am very green when it comes to Linux but I got it up and running and its really interesting.... I even learnt a few things.

[ChrisH]

I just got filtered out of this post because of the combination phrase "family filter is off" . Must finish doing my machine exceptions .

[MkII]

I have just chucked out our ISA2000/N2H2 Filtering and replaced it with:

 

Smoothwall 2.0

Dansguardian

Clam Anti Virus

Advanced Proxy Filter

Advanced URL Filter

 

and as a result NOTHING (well almost) gets through, it has made my life SOOOOOO much easier in this area.

 

Best of all its free and only took 2-3 hours to get up and running 1 day to fully configure and 1 week of solid out of hours testing.

 

{edit}

did i mention the fully featured web frontend to the whole thing

{/edit}

 

When you say "nothing gets through" do you mean the google searches don't return brief excerpts as mentioned in post 1, and the thumbnails that google caches don't appear either??

 

We have the medium option 'moderate filtering' enforced - maybe we'll change that.

[ChrisH]

Just had a look at all the smoothwall stuff. Theres a good community there for all the addons. I have basically done virtually all the stuff that this lot does but without the nice integrated GUI for everything I may have to give it a spin Now I really must go to bed rather than looking at work stuff at this time on a friday night 8O 8O

[Peter]

Web filtering? . . . you do it because you want to protect pupils/students from unacceptable web content such as pornography?

 

But, pornography and other unacceptable content is now readily available from most P2P networks. Kids can easily run a copy of bitcomet or blubster P2P (executable file) client on their USB sticks and get easy access to content most would find offensive. i.e Ken Bigley video. Xdcc is another example of how kids can easily get access to unacceptable content from the internet - Xdcc utilises IRC with bots to distribute file lists for file sharing. Xdcc is not new but has made a comeback recently, with colleges and unis finding they have hacked servers providing disk space for file sharing by Xdcc.

 

Please keep in mind unacceptable content is not only delivered through http.

 

regards Peter.

[Guest]

but any school proxy should have P2P ports closed as a matter of course. If I went to a school that could use access torrents, P2P etc, I would be asking what the IT department are playing at!

[ChrisH]

Most of the ports for everything but web/ftp/mail etc is usualy blocked at a local level and at the county level depending on your setup.

You make a valid point but I dont think this has ever been a problem in most schools. Schools that have their own independent connection this would probably be a problem but any half decent sys admin would have this bolted down.

Even if this kind of stuff is run over the http proxy which should be forced there should be restrictions on files and file sizes that they can d/l. There are lots of other ways to block things and at the same time get around them using MAC address which can be faked or stoping certain useragents from going through your proxy which can also be faked. So yes there are many ways to get hold of inappropriate material besides http but there also also many ways to block them.

No system is perfect but we try our best and will contantly review and see how things could be done better.

As for running stuff from removable media this should be locked down using policies.

[jonny_valentine]

I have a head teacher who is unhappy as while searching "welsh dragons cartoon pictures" in google came across some sites advertising porn/sex etc.

 

The sites were blocked but you could still see the Blurb about the sites i.e."cum here to see naked fcuk pics" etc etc.

 

Anyone use any soft that prevents sites with these words from being displayed ?

 

 

Hi,

 

Check this image out: http://www.imperosoftware.com/images/impero3.gif

 

Its the blocking system of the software we use in the schools i work at. You can easily block anything. For example, block 'fuck', 'porn' and so on and Impero will detect that in the page somewhere and not show it.

[DMcCoy]

I have a head teacher who is unhappy as while searching "welsh dragons cartoon pictures" in google came across some sites advertising porn/sex etc.

 

The sites were blocked but you could still see the Blurb about the sites i.e."cum here to see naked fcuk pics" etc etc.

 

Anyone use any soft that prevents sites with these words from being displayed ?

 

 

Hi,

 

Check this image out: http://www.imperosoftware.com/images/impero3.gif

 

Its the blocking system of the software we use in the schools i work at. You can easily block anything. For example, block 'fuck', 'porn' and so on and Impero will detect that in the page somewhere and not show it.

 

And again with the self advertising See here

[ChrisH]

Its the blocking system of the software we use in the schools i work at. You can easily block anything. For example, block 'fuck', 'porn' and so on and Impero will detect that in the page somewhere and not show it.

 

Which can be done for free with Dansguardian...

[ICTNUT]

Mark Said:

When you say "nothing gets through" do you mean the google searches don't return brief excerpts as mentioned in post 1, and the thumbnails that google caches don't appear either??

 

We have the medium option 'moderate filtering' enforced - maybe we'll change that.

 

I have the naughtyness level set to 95, goolge image search forced to use safe=strict via a url re-write, and the blacklist available from urlblacklist.com.

 

Using the above and a few extra mods found at the smoothwall community the level of AUP violations by both students and teachers has dropped right off.

 

Peter Said:

But, pornography and other unacceptable content is now readily available from most P2P networks. Kids can easily run a copy of bitcomet or blubster P2P (executable file) client on their USB sticks and get easy access to content most would find offensive. i.e Ken Bigley video. Xdcc is another example of how kids can easily get access to unacceptable content from the internet - Xdcc utilises IRC with bots to distribute file lists for file sharing. Xdcc is not new but has made a comeback recently, with colleges and unis finding they have hacked servers providing disk space for file sharing by Xdcc.

 

Of course you are correct however school proxies should have these ports closed and/or filtered, although saying that you can not be too sure that the central proxy provided by your county will have them closed or even monitored so we took the steps of blocking all stuff like P2P and bit-torrent at our firewall level.

 

This was done by using a combination of port blocking, packet/bandwidth shaping, throtelling outgoing bandwidth also the fact that students are unable to install anything on the workstations pretty much eliminates this issue.