Re: [OS:N:] Re: School Filtering

[Eric Harrison <eharrison mail mesd k12 or us>]

On Wed, 18 Sep 2002 MOliveri gswhs grundy k12 il us wrote:

>Hi folks,
>
>I run a high school network, and this probably refers to CIPA - the 
>Children's Internet Protection Act. It requires filtering to be installed 
>in schools and libraries if they want to continue to receive federal 
>E-Rate funding, which is essentially discounts on telecommunications fees, 
>equipment, etc. For instance, based on our demographic, our school is 
>eligible for a 40% discount on telecom services, including phone bills and 
>our T1 line.
>
>The NICE thing about CIPA, however, is the form of that content filtering 
>is a completely local decision. Schools can be as loose or tight with the 
>filtering as they want. In my case, I don't subscribe to the filtering 
>service from our hardware vendor for two reasons: it's expensive and it's 
>too restrictive. Instead, I have an option of what keywords I want to 
>block, what domain names, etc. This also means if a legit site is being 
>blocked, I can have the problematic keyword removed from the filter in 
>minutes, if not seconds.


I run a fairly large K-12 network ("paying" customers account for about
100,000 students).

We have about four years of filtering in a school environment and have
a really good idea of what works and what doesn't. If it's done right,
filtering is *GREAT* for schools, if it's done wrong it is miserable.

Our goals for filtering were/are to 1) minimize classroom disruptions from
accidental encounters with "obscene" material, and 2) provide a solid
audit trail when disciplinary actions are needed (i.e. we can show
that the kid had to *work* to get to those sites, proving intent).
When CIPA was passed, we used the "local determination" clauses to define
our requirements as exactly what we had working ;-)

We had fairly good experience with a proprietary filter when we first
started filtering. It was expensive, it significantly decreased the
reliability of our network, and required constant changes to the database,
but overall it was better than not filtering at all. Generally teachers
where happy to avoid the disruptions in exchange for the occasional
blocking of valid research material & the several-times-per-week crashes
of the filter servers.

Then our proprietary filter blew up, never to work again. I threw 
squidGuard (www.squidguard.com) onto our squid proxy filters as a stop-
gap measure while the vendor tried to get the proprietary filter back
into production. Out of the box, squidGuard performed as well as the
proprietary filter. This happened right when CIPA passed. After running
squidGuard for a week while the proprietary vendor floundered, we were
informed that our contract would increase significantly when it was time
to renew.  The school districts I support asked if I would just cancel the
expensive support contract and leave squidGuard in place.

Since then, I've been able to refine squidGuard to fit our needs. Since
it's GPL software, I've been able to make it work better and give those
improvements back. I used to spend a couple hours per week keeping the
proprietary software working, now I volunteer a couple hours per month to
help make squidGuard work even better ;-)

Since it's GPL software, I'm not stuck using the same source for the
filtering technology and the filtering rulesets. SquidGuard itself
works *flawlessly*, but the blacklists provided on the squidguard site
did not fit my needs as well as they could. Squidguard.org provides the
software they used to generate their blacklists, so I downloaded that and
modified it for our needs. I then merge in the blacklists generated by
Universite Toulouse in France and Burgernetz Pfaffenhofen in Germany, 
both of which produce blacklists of excellent quality.  I then export out
the combined lists to whoever wants it (http://squidguard.mesd.k12.or.us,
~10,000 downloads in the last two weeks).

For those who have different filtering goals and objectives than the schools
I support, Dan's Guardian (www.dansguardian.org) is a popular alternative.
Dan's Guardian web site (another GPL web filter, a "competitor" to squidGuard)
has links to my squidGuard blacklists, which users of Dan's Guardian can use
to enhance that product.  They won't even get slapped with the DMCA for such
an offense ;-)


-Eric