EMAIL PRIMER
FILTERING
ENVISIONWARE
ENVISIONWARE-DROPPING FILTERING
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Filtering
Summary
In order to comply with CIPA, ESRL provides web filtering for staff
computers, public computers, as well as devices that the customers
connect to the library's wireless network.
Filtering System
The filtering system is a DNS based system, using software from nxfilter.org,
in conjunction with a commercial filtering list called jahaslist. We simply refer
to it as nxfilter. The 2 proxies that ESRL maintains (filtered and unfiltered)
are both using this new system. This system is resilient and scales
significantly better than any other system we investigated.
Policies
Currently, these categories are blocked: Phishing/Malware,
Warez/Torrent, Hacking, Porn, and Test (ESRL's testing category)
Antivirus
In addition to the filtering policy, all filtering also includes
some antivirus, antimalware and anti-phishing protection. This
protection is not expected to be perfect or comprehensive (none
ever is) and is not a replacement for antivirus software or common
sense.
Filtering on Staff Computers
ESRL suggests that staff computers, at a minimum, use our
"unfiltered" filter which includes only the virus/malware/phishing
protection. Staff computers may have stricter settings based
on local library system policy.
Filtering on Public Computers
The filtering on library owned public machines is managed
through Envisionware, and can be enabled or disabled (based
on local library policy) through Envisionware.
Envisionware - Dropping Filtering
Filtering on the Public Wireless
Filtering on the wireless segment cannot be disabled individually.
If a customer needs an unfiltered connection they can be signed in to an
unfiltered session on a public computer.
We are unable to filter any device that has its own data plan, only devices that connect to the library wifi.
What you see when content is blocked
The screen that you will see if a page is blocked by the
filtering system looks like this:
The reason the page is blocked is given in parenthesis, in this
case "Test".
Testing the filtering
ESRL has provided a test url that can be tried, to see if filtering is working
properly at your site. That url is http://blocked.esrl.org/
If you click this link, and see a message about BROKEN FILTERING, please contact
systems @ esrl . org and let us know what went wrong.
Reporting a problem or wrongly blocked site
ESRL makes every effort to ensure that legitimate sites are not blocked
accidentally; however no system is perfect. In the event that a legitimate site
is blocked, or some other problem happens with filtering, contact
the ESRL helpdesk and let us know about the issue.
Reporting a site that should be blocked
No filtering database is perfect, and new sites crop up all the time. If
there is site that a user is going to that violates library policy (ie, porn),
then make a note of the website and contact the ESRL helpdesk to let us know
about the issue.
Categories
The "Category List" link takes you opens a new page describing all the possible filtering categories.