Port filtering allows you to block outgoing internet connections and permit only selected applications to access the internet. Traffic is identified by port numbers. Some applications are pre-defined. You can define additional applications if you know the details of the traffic used and generated by the applications.
NOTE: You can view whether port filtering is on or off in the Settings panel on the web UI Home page.
NOTE: When IP Passthrough is turned on, port filtering capabilities are set through the connected host routing system and settings on this page are not available.
Port Filtering: To turn on port filtering, move the on/off slider to on. To turn off port filtering, so that any application can connect to the internet, move the slider to off.
Select the applications you want to be able to access the internet and click Save Changes.
The following table provides port numbers and protocol information for each port filtering application listed.
Application | Port | TCP* | STCP* | UDP |
---|---|---|---|---|
Email (POP3) | 110 | Yes | No | Assigned |
Email (POP3S) | 995 | Yes | No | Yes |
Email (IMAP) | 143 | Yes | No | Assigned |
Email (IMAPS) | 993 | Yes | No | Assigned |
Email (SMTP) | 25 | Yes | No | Assigned |
Email (SecureSMTP) | 465 | Yes | No | No |
FTP control (command) | 21 | Yes | Yes | Assigned |
FTP data transfer | 20 | Yes | Yes | Assigned |
HTTP | 80 | Yes | Yes | Assigned |
HTTPS | 443 | Yes | Yes | Assigned |
Telnet | 23 | Yes | No | Assigned |
*Yes - indicates the protocol is standardized for the port number.
No - indicates the protocol is not standardized for the port number.
Assigned - indicates the port number is assigned by IANA (Internet Assigned Numbers Authority) for protocol use but may not be standardized. |
You can define up to ten custom applications.
Add custom application: Use this button to add a new row to the custom application list.
Click Save Changes to save any changes made to the custom applications.