User guide

Chapter 8 Access Restrictions
92 3425-00669 Rev E
 To use Website Blocking by Regular Expression, enter the expression you
wish to block in the fields provided.
Note: A regular expression is a string used to describe or match a set of
strings. You can block websites that use strings encompassed by the regular
expressions you enter on this screen. Enter each regular expression in a
separate field.
Regular Expression Syntax:
.
any character
^
start of a line
$
end of a line
*
match zero or many times
?
match zero or one time
+
match one or more times
{m,n}
match from m to n times (m <= n)
{n}
match exactly n times
[a-c]
character set
[^a-c]
negative charset
|
or
(“ and “)
brackets for grouping
\xx
escaped character
4 Use any combination of the following options to block services in the Blocked
Services section to filter access to various applications accessed over the Internet,
such as FTP or telnet.
 Block a preset applications—The block services select list offers a choice of
preset applications. For multiple selection, press the Ctrl or Shift key.
Note: If you select a preset application, its port numbers and protocol are
displayed and can not be changed.
 Block a new service—If the application you want to block is not listed, select
the Service link; then, you can enter the port range and protocol for the
service you wish to block. The new service is added to the list.