3Com OFFICE CONNECT CABLE/DSL SECURE GATEWAY 3CR856-95 User Manual

Contents

495 Either:■ Enter the additional services that you wish to allow in theexcept (specify ports) box and set the drop down box toAllow.■ Enter the services that you wish to deny in the except (specifyports) box and set the drop down box to Deny.Enter multiple ports as either a comma separated list e.g. 101,105, 107, or as a range, e.g. 101-107.6 Click Apply to save the settings.Example: Allowing only web and E-mail access.To allow web and E-mail access and block all other servicesacross the Gateway’s firewall:■ Ensure that the Control PC Access to the Internet radio buttonis selected.■ Click on All PCs to pop up the PC Privileges window.■ Ensure that the Email (110,25) and Web (80) boxes arechecked and that other check-boxes are left cleared.■ Set the Block or Allow other services: drop-down box to Blockother services.For the purposes of this example, your users also need to accessa test web server on port 8080. To allow this:■ Enter the number 8080 in the except (specify ports): box.■ Click Apply to save your changes and close the PC Privilegeswindow.VPN connections to other networks are unaffected by settings inPC Privileges. To allow or deny VPN connections to othernetworks see “Configuring VPNs” on page 53.Special ApplicationsSelect Special Applications tab to display the AuthorizedApplication setup screen. See Figure 47 below.Figure 47 Special Applications ScreenSome software applications need a connection to be started fromthe Internet — an act that is usually blocked by the Gateway’sfirewall.dua08 569-5aaa02.bo o k Pag e 49 Thursday , No vem ber 7 , 2002 3:09 PM