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An Introduction to Filtering: Issues and Possible Solutions

Sarah Ormes

UKOLN

University of Bath

Bath, BA2 7AY

UKOLN is funded by the Library and Innovation 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.

Emails.l.ormes@ukoln.ac.ukURLhttp://www.ukoln.ac.uk/

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Libraries and the Internet

•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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Is Filtering the Answer?

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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?

•Three main methods used:• Keyword blocking• Site blocking• Web rating systems

•Combinations of the above•Installed at a client or server level

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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

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Site Blocking (2)

•Some software provides control over what categories of information you block•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 NudityLevel 3: Frontal NudityLevel 2: Partial NudityLevel 1: Revealing AttireLevel 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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How Well Does Filtering Work?

•Research shows that it doesn’t always work

• unsuitable sites not blocked• suitable sites blocked

•Software developing all the time•Unlikely ever to be failsafe

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Reasons to Use Filtering Tools (1)

•Selecting the best resources• what libraries have always done

•Children and pornography• making the library as safe an environment as

possible

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Reasons to Use Filtering Tools (2)

•Legal issues• protecting the library from legal challenges

•Patron’s peace of mind• knowing the library is providing a safe

environment

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Reasons Not to Use Filtering Tools (1)

•Freedom of access to information• Provide access to all legal information

•Who decides what is filtered?• How sophisticated are the selections?

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Reasons Not to Use Filtering Tools (2)

•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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Selecting a Filter (1)

•It’s hard work and takes time!

•Decide what you want it to do - there are different options

•Try several out - find one that matches most closely your wish list

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Selecting a Filter (2)

•Test it and test it again

•Tell your users what you are doing and why

•Back it up with a policy!

(from A Practical Guide to Internet Filters by Karen Schneider)

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Managing Access without a Filter

•Draw up an acceptable use policy•Offer training classes for parents and children•Can children surf alone? Do they need their parent’s permission?•Provide useful collections of links

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Internet Access Policies

•Sign an acceptable use policy?•Filtered or unfiltered?•Filtered for whom?•Time constraints• Restrictions on services (chat? Email?)

• Parental permission?•Age limits?•Who may use?• How do policies relate to other library policies?•What happens when people break the acceptable use policy?

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Whether you filter or don’t filter - have a policy!

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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/lis-99/