IP: Australian Government releases content filtering survey in time for Philadelphia trial

[David Farber <dfarber () earthlink net>]

-----Original Message-----
From: Nathan Cochrane <ncochrane () theage fairfax com au>
Date: Tue, 26 Mar 2002 13:08:08 
To: Dave Farber <dave () farber net>, Declan McCullagh <declan () well com>
Subject: Australian Government releases content filtering survey in time for Philadelphia trial

Hi Dave, Declan

Call it kismet, providence or good timing, but the Australian Government 
has released a 90 page report into the effectiveness of censorware as 
the CIPA goes to trial in Philadelphia.

http://www.interesting-people.org/archives/interesting-people/200203/msg00184.html
http://www.politechbot.com/p-03297.html

The report was commissioned by the Australian Broadcasting Authority 
(www.aba.gov.au), which is responsible for censoring the Internet in 
this country, and conducted by the Commonwealth Scientific and 
Industrial Research Organisation (www.csiro.gov.au).

http://www.aba.gov.au/internet/research/filtereffectiveness.pdf

"Effectiveness of Internet Filtering Software Products" gives a basic 
background to the problems of censoring Internet content. It then 
addresses the different approaches vendors use, such as 
inclusion/exclusion, content, source and image filtering. It finishes by 
reviewing 14 products and services including Cyber Patrol 5.0, AOL 
Parental Control 6.0 and Net Nanny 4.0.

The report doesn't take a moral or ethical stance, but outlines what can 
be achieved with the technology available.

Some highlights from the report:

"While it is technically feasible to block access to all undesirable 
Internet content, no Internet blocking or filtering scheme will ever be 
100% effective, or resist a determined and informed attacker, but many 
of them will be perfectly adequate in normal use."

"A completely safe Internet may well be a very restricted Internet, 
especially when new types of content and new distribution technologies 
emerge."

"Many filtering products are based on lists of Web sites that are 
supplied by their vendor. These lists are expensive to produce, as they 
have to be compiled by having people examine and classify Internet 
content, and as a result these lists are often closely held proprietary 
information. The secret nature of these lists can make it difficult to 
know just what content is being blocked and for what purpose.

"These lists also reflect the values of the organisations and people who 
compile them, and may not reflect the values of Australian society as a 
whole. Some Internet activists (Peacefire) complain that commercial 
filtering products reflect US-based conservative and religious values, 
and as such may not reflect the more liberal values held by Australian 
society. Cultures differ considerably in their concepts of acceptable
content and filtering products really have to customise their lists to 
meet local cultural norms."

"Content filtering is a difficult problem. Even text-based filtering 
requires some ability to determine context (and meaning) for words they 
discover. Early products were infamous for simplistic filtering, with 
the blocking of "breast" cancer content being the most quoted example. 
Filtering products have improved since those early days but the task is 
still very difficult and moderately high error rates can be expected. 
Filtering out non-textual information, such as photographs or video, is 
much more difficult and problematic."

"All filtering technologies are fallible, and the more effective they 
are, the more they risk intruding on general Internet usage. Products 
have to strike a balance between filtering out undesirable content, and 
allowing access to (possibly unknown) useful content. The white list 
products are the most effective because they are the most restrictive 
and constrain users to a very small part of the Internet."

"Much attention is paid to filtering Web pages but undesirable content 
can be found in many places on the Internet, including newsgroups and 
file servers. Some of the more tightly filtered Internet services, such 
as some of those designed for the educational market, resolve this 
problem by completely blocking access to all Internet services other 
than the Web and e-mail. This approach is certainly safe, but would be 
unacceptable for the general Australian community and so these other 
sources may have to be filtered as well."

"An emerging problem with filtering Web traffic through the use of 
server-side filters is the rapidly increasing use of the Web's protocol 
(HTTP) and port (80) for other purposes, such as e-commerce and Web 
Services. Filtering all HTTP traffic could result in degraded 
performance for major applications, rather than just slowing down
interactive Web browsing."



*********************************************************************************
This email and any files transmitted with it may be legally privileged 
and confidential.  If you are not the intended recipient of this email,
you must not disclose or use the information contained in it.  If you 
have received this email in error, please notify us by return email and 
permanently delete the document.
*********************************************************************************

For archives see:
http://www.interesting-people.org/archives/interesting-people/