DoS Attacks Problem - Urgent Help Required
A few weeks ago our office installed a new system meaning all computers were networked together. This means that our internet was now supplied using a Wireless ADSL Modem Router. This was fine until a week ago when our network guy called me to tell me that the system was being hammered with over 10 DoS attacks per second which slowed down the system considerably. He narrowed the problem down to my machine and ultimately to my using BitComet and filesharing.
I need to know is there any way around this problem? Are there any alternatives to BitComet which will allow only downloading so that I can then copy files to another PC and (upload) seed from the second machine? Is there any software which can stop the DoS attacks?
Any sugeestions gratefully accepted.
Re: DoS Attacks Problem - Urgent Help Required
I think possibly either you or the network guy may be misunderstanding what's happening.
By slow down; do you mean the internet connection, or the computer's performance? I'm assuming the former. Also, what is your connection speed and PC spec (processor and ram).
I guess the number of connections per second to a PC because of a bittorrent client could be thought of loosely as a dos attack - but it isn't really, even tho' BitComet may be hogging all of your bandwidth, dos (denial of service) attacks are normally thought of as malicious.
To prevent this problem from occurring, if indeed it is bandwidth related, install a program called Netlimiter and set it such that BitComet can only use between 50% and 75% of the available bandwidth, this should let users of the other PCs browse normally.
Re: DoS Attacks Problem - Urgent Help Required
Quote:
Originally Posted by manker
I think possibly either you or the network guy may be misunderstanding what's happening.
It's very likely me that misunderstands. Although a computer user for some years, I just like telling my PC what to do and letting it get on with sorting out how to do it.
Quote:
Originally Posted by manker
By slow down; do you mean the internet connection, or the computer's performance? I'm assuming the former.
Yup, the internet.
Quote:
Originally Posted by manker
Also, what is your connection speed and PC spec (processor and ram).
Speed: 100.0 Mbps
PC Spec: AMD Athlon XP 2200+, 1.81 GHz, 504 MB of RAM
Quote:
Originally Posted by manker
I guess the number of connections per second to a PC because of a bittorrent client could be thought of loosely as a dos attack - but it isn't really, even tho' BitComet may be hogging all of your bandwidth, dos (denial of service) attacks are normally thought of as malicious.
To prevent this problem from occurring, if indeed it is bandwidth related, install a program called
Netlimiter and set it such that BitComet can only use between 50% and 75% of the available bandwidth, this should let users of the other PCs browse normally.
Will speak to him about it, try NetLimiter and get back to you.
Thanks a lot for the advice
Re: DoS Attacks Problem - Urgent Help Required
No probs, I think Netlimiter should sort out the problem. The version I pointed you to is a legitimate free-trial but as a filesharer, you'll be aware that there are ways around paying for the full version - downloading it off Torrentspy, for example.
;)
Re: DoS Attacks Problem - Urgent Help Required
Quote:
Originally Posted by manker
No probs, I think Netlimiter should sort out the problem.
Nope, it didn't help - thanks for the advice though.
Anyway, I showed all the responses to the network guy who responded:
"I read the replies. I don't know what the actual data is but the router reports it as being DOS attacks.
Maybe because of the way it works and makes 10 connections at a time it seems like DOS attacks I dont know but either way it slows down the whole network.
I have tried some of the options like port forwarding but it didnt help.
The problem with downloading in the evenings and weekends is firstly the permitted remote users might try to connect at that time and secondly the attacks continued for a few days after stopping BitTorrent which might just be people trying to download from you but it doesnt help us because they continued trying."
Aaaaaargh!
Any other ideas?
Re: DoS Attacks Problem - Urgent Help Required
Try another bt client and limit your upload to say 20% of your bandwidth(not bad for a 100mb pipe!).
Re: DoS Attacks Problem - Urgent Help Required
It sounds to me like your ul may be getting saturated and then slowing your dl speeds. If you know what is your ul speed I would be curious as to what it is. Try to setting that in NetLimiter also so that your ul is capped at somewhere around 80% or lower of your total ul speed and see if that brings any cure though Im not sure it will in your situation.
It seems the way your network is setup the router being the main part of it just dosent like mass simeltanious conections and is freaked. I also wonder if the router is an older model or in need of a firmware upgrade. The only other suggestion I can make if nothing else works is possibly a different way of getting your stuff like Newsgroups. You can take a look around the section we have here which should have all you need to get you going should you want to check it out...
Re: DoS Attacks Problem - Urgent Help Required
Thanks I will try the suggestions above and if I find a solution (fingers crossed) post it here.
Cheers!
Re: DoS Attacks Problem - Urgent Help Required
Re: DoS Attacks Problem - Urgent Help Required
got a problem too, i'm using VSAT connection, and upload often crash my vsat transmission box.:(