NxFilter Tutorial

CxBlock for browser filtering
CxBlock is a browser level filtering agent. You can use it as a remote filtering agent. And you also can use it in a local network to supplement NxFilter by URL keyword filtering.

To use CxBlock as a remote filtering agent, use your public IP as its server address.


Installation of CxBlock
CxBlock is a Chrome/Edge extension. You can install it from Chrome Web Store and Microsoft Store.

    - CxBlock on Chrome Web Store
    - CxBlock for Edge on Microsoft Store


Connection to NxFilter
After you install it, you need to set up the following parameters on its setup page,

- Sever Address : The IP address of NxFilter.
- Login Token : A login token associated to a user on NxFilter.

Once you set up the parameters you can test the connectivity using Test button. And then you can save and reload the new configuration.

To use CxBlock, you have to enable user authentication on 'System > Setup'.


User identification
We use Login Token and Google/Microsoft Account to identify users. Suppose you create a user named 'student' on NxFilter and install CxBlock to 100 Chrome browsers with the login token of 'student' user. Before they login to Google they will appear on NxFilter log view as 'student'. But if one of them login to Google using 'john1234@gmail.com', then he will appear as 'student_john1234'. And if you create 'john1234' on NxFilter then he will appear as 'john1234'.


Central configuration file
When you install CxBlock en masse, you don't want to set up its connection parameters one by one. To make things easier, we have a way for setting up these values centrally. We use Chrome/Edge start page. You write a webpage containing some common config values and then make the webpage to be the first start page of Chrome/Edge. Then once your users start their Chrome/Edge, they will set up their CxBlock with the config values from the start page.

When you write the webpage you add a meta tag like the following,

<meta name='cxblock' content='192.168.0.101:4RYEO5P2'>

We have 2 parameters separated by colons. The first one is NxFilter IP address and the second one is a login token of a user.

If you mass install CxBlock for filtering in your local network only. You don't need to set Login Token. After you install CxBlock, it will try to find its server by itself and then it will start working without Login Token.


Auto setup in a local network
If it's just for local network filtering, you can let CxBlock find its server by itself and let it work without Login Token. CxBlock tries to find its server at startup and then it tries to find an associated user based on its IP address. So, the user running CxBlock without Login Token should be logged in already or associated to an IP address of the user system. To make things easier, we recommend you to create a default user associating an IP range covering whole network.

If it's with NxCloud, you have to use Login Token.


URL keyword filtering
CxBlock supports URL keyword filtering. You can block URLs containing specific keywords or regular expressions. With regular expressions, you can make a bit sophisticated filtering rules. For example, if you want to block 'porn' an 'vpn' for Google and Bing only, you can add a regular expression like below into 'Policy > CxBlock > Blocked Keywords in URL'.

/(google|bing)\.com.*(porn|vpn)/


Force install of CxBlock
There are several ways of force install CxBlock into user systems. If it's for Edge, you can force install CxBlock through Active Directory GPO. And if it's for Chrome, you can use Google Admin. You also can force install Chrome/Edge extensions through Microsoft Intune.