Monthly Archives: May 2016

How to block IDM in network? WFilter added support for blocking IDM.

Internet Download Manager (IDM) is a Multi-threaded application that
breaks a file into many small parts and starts to simultaneously
download all of these parts. It can consume a lot of your bandwidth when downloading multiple large files.

With WFilter, you can block IDM downloading completely.

The settings are very simple. You only need to edit your blocking policy, and set “IDM” to “Deny” in “Applications”.

In “Connections”, you will see IDM connections are “terminating”.

IDM will report failure in a few seconds.

A protocol description of IDM can be found at: How to block IDM, IDM port and protocol description. Please note that downloading from https with IDM can also be blocked.

Web filter can not block youtube via chrome browser? Try WFilter.

Since chrome implemented QUIZ to server web requests, it has been a dark period for IT administrators because normal web filter won’t work to filter google/youtube sites. You may check more details at Why is Google’s QUIC Leaving Network Operators in the Dark?   A protocol description of QUIZ can be found at:

Our team has worked out solutions to block QUIZ, so you can get web filter back to working.

For WFilter Enterprise and WFilter Free, you simply need to block UDP port 443 in your router/firewall. Steps to block udp ports can be found at here:

For WFilterROS, please check this post: Do not forget to block QUIZ to block youtube and other google sites.

Do not forget to block QUIZ to block youtube and other google sites.

In google chrome, a new protocol named QUIZ, is implemented. The protocol description can be found at

It says QUIZ can improve website performance by 3%. However, because QUIZ is an UDP based encrypted protocol,  domains support QUIZ will not be blocked with WFilter’s web filter.

This issue happens in Chrome browser to Google sites only(including youtube). To make web filter working, you’re recommended to block QUIZ completely.

In pass-by deployment with WFilter Enterprise, you’re recommended to block udp ports “443 -65534″ in your firewall and router.

In WFilterROS, you can block QUIZ in the “app control” module.

Demonstrations of blocking youtube.

When QUIZ is not blocked, you can only see QUIZ traffic when visiting of youtube with chrome.


Block QUIZ in app control.


Now “QUIZ” connections are all blocked, and youtube can be blocked by WFilter.