Help! - CFP causing broadband performance drop

Requisite Info (yeah, I read FAQs):
Comodo Version:
Connection: Cable
OS: WinXP, SP2
Logging in as: Admin
Security Apps: AVG Antivirus
Removed Apps: ZoneAlarm Free (removed prior to installing CFP)


After reading a promising review, I uninstalled ZoneAlarm Free, and installed Comodo Firewall Pro. I had no problem with installation and configuration, but I noticed when visiting the Netflix site that individual images were loading much more slowly than usual.

I ran PC Magazine’s “SurfSpeed” bandwidth tester, that attempts to gather “real world” speed results, rather than simply transfer large files.

Sure enough, when I set Comodo’s security to “Allow All,” my speed tests run about 35-37KB/s, which is more-or-less what I expect. When I change the security level to “Custom,” the results drop to a meager 8-10KB/s.

This is a much higher performance impact than I anticipated. Can anyone tell me what is causing the slowdown, and how I can remedy the problem without having to compromise security any more than necessary?

Many thanks.

Ziff-Davis SurfSpeed:,1759,1960153,00.asp


Update -

I may have found the problem.

Under (Advanced Security Configuration > Application Behavior Analysis) the last option is “Monitor parent application leaks.” If this box is checked, then my connection suffers severely.

Also, the box above it, “Monitor DNS queries” has a considerable impact on broadband performance.

Has anyone else noticed performance problems related to these two settings?

No one? No one has experinced broadband slowdown issues resulting from CFP?

Hi Djinn, welcome to the forum.

I have ADSL and experience no apparent slow speeds as a result of CFP 2.4.x. Usually users with very fast internet connections may notice some speed difference, but seeing how your regular download is ~ 35 Kilobytes/second, that is another case (because it’s not fast to begin with). Hmm…

Monitor DNS might, but Monitor Parent should not affect speeds because that’s at the application/system level, not network level.

Maybe you should upload an edited sample of your log and see if something’s being blocked. I allow all ICMP In & Out in Network Monitor and it helps me a bit in uTorrent.

Many thanks for the response… My connection speed is actually quite quick for large files (which would include Torrents). I often get real-world speeds exceeding 1000KB/s when pulling down files. However the test I’m using simulates loading multiple web pages, which may contain 100 or more individual files. That’s why I noticed the slowdown on the NetFlix page. Assuming you’re a member, the default page includes graphics for over a dozen movies, and that’s where I saw the slowdown.

The problem is 100% repeatable… I can easily run the test, change the settings I described in my original post, run the test again, and see significant changes in the results. And I’ve confirmed that “Monitor Parent” has by far the most impact on performance.

I’m very new to CFP - I’ll be happy to provide log files these evening. Are they found within the application interface? Or are they in a system folder? Thanks again.

The CFP gui at the top: Activity > Logs > right click in this area and export to html. From thereon you can edit it to your liking with Notepad, Word or whatever program and upload here by clicking no the Additional Options… at the bottom left corner when you’re about to post something.

And I’m a member of the Moderators; a group of helping volunteers.

Weird… Try as I might, I can’t reproduce the problem today. Go figure. If you don’t mind my leveraging this thread, I’d like to bring up another problem I encountered.

I periodically set up an FTP server for the purpose of enabling specific people to download files from my machine. I don’t leave it up; I usually call the other party, say “Get it now,” give them the link, and make sure they’re able to download OK.

Last night, I was unable to get the connection working, and I have a hunch that CFP firewall is the issue. Here are four screenshots of my FTP software and my router settings for review… I’ve taken the liberty of blurring out vulnerable information.

I can safely vouch that the FTP app is registered with CFP, set for TCP/UDP In and Out “Allowed.” I would greatly appreciate any insights.

Many thanks.

Hi Djinn. I’ll leave the thread opened since we don’t know what the cause for the speed decrease is, and in case the problem returns.

As for the FTP server question, it really is off-topic and you should start a new thread or look at other threads like this one:

Many thanks… I’ll test the FTP settings per the linked thread, and if I’m still having problems, I’ll start a new thread.

All the help is most appreciated!