Transcript Powerpoint 97

Filtering - Is This The
Answer?
Sarah Ormes
UKOLN
University of Bath
Bath, BA2 7AY
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Email
[email protected]
URL
http://www.ukoln.ac.uk/
UKOLN is funded by the Library and Information Commission, the Joint
Information Systems Committee (JISC) of the Higher Education Funding Councils,
as well as by project funding from the JISC and the European Union. UKOLN also
receives support from the University of Bath where it is based.
Today we will cover …
What are filters, how do they work,
how well do they work?
Pros and Cons of Using a Filter
Things to think
about if you do
Things to think
about if you don’t
Acceptable Use Policies
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What’s the Question?
All libraries providing access to the Internet
need to address the following issues:
• Some users will deliberately access
and view pornography
• Children could gain access to
‘offensive sites’
• The library could by default provide
access to illegal material
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What is Filtering?
• Software which is used to control access
to material on the Internet
• Typically used to prevent access to
pornography and other potentially
offensive material
• Used in many organisations including
public libraries and schools
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How Does it Work?
• Four main methods used:
• Keyword blocking
• Site blocking
• Web rating systems
• Walled Garden approach
• Combinations of the above
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Keyword Blocking
• Uses a list of ‘objectional terms’
• Blocks any or part of pages/e-mails
containing these words
• Can be inaccurate e.g. Essex, Dick
Whittington, Penistone could be blocked
• Generally viewed as the least
sophisticated method
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Site Blocking (1)
• Software company maintains a list of
‘dubious Internet sites’
• The software prevents access to any sites
on this list
• ‘Denial lists’ regularly updated
• Some software provides control over
what categories of information you block
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Site Blocking (2)
• Who decides what goes on the ‘denial list’
and what criteria are they using?
• Can you keep track of the whole Internet?
• Filters can use both site blocking and
word blocking.
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Web Rating Systems (1)
Web sites rated in terms of nudity, sex,
violence and language
RSACI Nudity Categories
Level 4: Provocative Frontal Nudity
Level 3: Frontal Nudity
Level 2: Partial Nudity
Level 1: Revealing Attire
Level 0: None of the Above
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Web Rating Systems (2)
• Ratings either done by web page author
or by independent bureau
• Browsers set to only accept pages with
certain levels of ratings
• Very low take up so far
• Who decides the ratings?
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Walled Garden Approach
• Only provide access to a set of approved
links
• Analogous to book selection
• Time consuming and hard work
• Means users will only have access to a
tiny percentage of Internet resources
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How well do they work?
The Internet Filter Assessment Project
•Over 35% of the time, the filters blocked some
information needed to answer a question
•Eight percent of what filters accessed they
determined was ‘objectionable’
The Internet Filter Assessment Project
http://www.bluehighways.com/tifap/
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Stories From the Web
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Stories from the Web
through a filter
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Searching for
‘SXXXXhorpe’
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Slipping through the Net (1)
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Slipping through the Net (2)
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www.whitehouse.com
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At the Moment…
• Filters do not work perfectly - they block
valid resources and they don’t block
some objectionable resource
• Filters do block a lot of objectionable
material
• Filters are the only product available at
the moment
• Is it a matter of what your acceptable
level of failure is?
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Pros
• Deselecting poor quality resources
• haven’t libraries always done this?
• Children and pornography
• making the library as safe an environment as
possible
• Legal issues
• protecting the library from legal challenges
• Being seen to be doing something
• public knows the library is trying to provide a
safe environment
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Cons
• Freedom of access to information
• The library starts censoring
• Who decides what is filtered?
• How sophisticated are the selections?
• The library as the information ‘safety net’
• The only access point to the Internet for
some users
• Legal issues
• Can you provide a safe environment with
filters?
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Providing an appropriate
Internet environment
• A filter is not THE solution
• It is one step of managing access
• It is not an easy option
• Incorporate filtering into an
implementable policy
Choosing a Filter Presentation
http://www.ukoln.ac.uk/public/present/nag/
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The Perfect Filter!
• Blocking can be en/disabled
• Access to list of blocked words and sites
• Add/remove words and sites from lists
• Blocking based on PICS
• Blocking by time, location, status of user
• Methods of alerting users these products
are in use
• Understandable ‘blocked’ message.
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Managing Access without
a Filter
• Offer training classes for parents and
children
• Privacy screens?
• Can children surf alone? Do they need
their parent’s permission?
• Provide useful collections of links
• Publicise your rules
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Draw up an Acceptable
Use Policy
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Essential Policy
Components (1)
• Why does the library provide Internet
access (relate to other library policies)?
• What type of material can be accessed
on the Internet? (warning)
• What responsibility does the library have
for material accessed and how this
material is used?
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Essential Policy
Components (2)
• Who will be able to use the library’s
Internet workstations?
• What type of resources can/can’t users
access?
• How do you expect your users to act?
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Essential Policy
Components (3)
• What will happen if they break these
rules?
• What are the rules about children?
• Do they need parental permission?
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Essential Policy
Components (4)
• Filtering
• Does the library filter?
• Why did it decide to filter?
• How was the filtering tool chosen?
• What does it do?
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Access, Security and
Control
• Access
• What kind of access do you want to
provide and why?
• Security
• Do filters answer your security
problems?
• Control
• Is your library in control?
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Further Information
• An Introduction to Filtering - available at
•http://www.earl.org.uk/taskgroups/
policy/issue_papers/nocolumns.htm
• Schneider, K. (1997) A Practical Guide to
Internet Filters. Neal Schuman: New York.
• Other links and this presentation at
http://www.ukoln.ac.uk/public/
present/london/
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