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Blocking MSN Messenger?
Tekno2k3 asks: "As a sysadmin for a financial company, I have been tasked with removing Instant Messaging from our network. The only service that is being difficult is MSN Messenger. It uses many methods to get around being blocked. These include using port 80, using it's own DNS servers for lookup, using MANY logon servers, and using reverse DNS lookup. Has anyone had any success in blocking Messenger?"
Disable MSN Messenger via group policy.
Fire everyone who's caught using it. Eventually you'll fire enough people that they'll be afraid to open it. Just like the RIAA suing P2P users... eventually nobody will share because they'll be afraid of lawsuits.
Block port 1863 (tcp) at the router/nat box/whatever.
On your web proxies (if you have them), block HTTP messages with the mime type "application/x-msn-messenger" and turn off HTTP CONNECT support for port 1863.
Turn off SOCKS for port 1863, too.
Have you tried Packeteer? Many educational institutions use it to shape and manage traffic. They also have a help page describing how to control instant messaging including MSN.
Use a packet shaper. The one that comes to mind (proprietary, however) is Packeteer. These filter based on protocol (I think), so usually they can keep out resourceful programs like gnutella, etc.
Everyone is getting all technical about this but it's very easy. Just block messenger.hotmail.com. Walla msn messenger stops working. It connects to this central server to find out what server to use.
Hacker Media
This is a very inelegant approach, but I suppose you could block EVERY logon server at the router. There has to be a finite number of logon servers out there, so all you'd have to do is sit down for X amount of time with a MSN client and monitor outgoing traffic from your IP. Block each logon server as it comes up, wait for the client to reconnect, block that server, rinse, repeat.
Also, you could try looking for the location that the MSN client fetches the server list from and block that IP. If the list is stored locally, it'd be even easier to find and block those servers.
Of course, the above approach assumes that the router can handle blocking X amount of IPs. I wouldn't put it past MS to have hundreds or thousands of servers out there.
Then log all access to port 1863.
In addition to blocking MSN on the network, why not kill the software? This page discusses in gory detail the various methods of crippling/uninstalling/haxoring MSN software on the user machine, and making sure it won't come back. You have to be careful, as there are right ways and wrong ways to do it. My favourite method is to uninstall the software (made possible on XP via a convoluted run command), then place a blank file called "msn messenger" in Program Files. Installer won't work, and the user never goes into Program Files! It works.
Having the software right out of the computer is a good thing, because then it can't begin to pester the user or remind them of their painful inability to chat.
Blcoking 1863 does work, as I use that method myself.
? suckerid=bIcycleSExfiEND&referrid=1269
... etc... you get the idea.
The only problem is that they will move on to the next messenger that works (like Yahoo! etc).
If you wanted to be really insidious and get people to self police themselves, log all messenger messages and put a new section on your companies Intranet user customised page - something like "Hello xxxx, here are your last few messenger messages:
[bIcycleSExfiEND] w00t!
[cute^babe7599] SO BABEE U WANA C MY PIC?
[bIcycleSExfiEND] yeah - send it
[cute^babe7599] http://www.crackparty.com/showpictrojanisemachine
...
Please contact the helpdesk if you would like a complete log.
Have a nice day."
...and below that:
Here are your last few web accesses:
The real question here is why block MSN? What about people who use instant messaging for legitimate business purposes?? People chat on telephones, and I don't see many offices rushing to ban them. Fire unproductive people, and let the rest of us communicate.
One future, two choices. Oppose them or let them destroy us.
Hey,
you can block stuff like this using Group Policies (GPO's). I think you should start asking at news.microsoft.com at their group policy newsgroups.
If you have windows XP's as a member of your domain, you can easily block it using GPO.
Get a MSN sniffer... the (very beta) one I used was called MSN666.
Tell everyone that you're sniffing MSN messenger traffic, and that you can trace it to a person esaily. Wait a day. Post a few innocuous messages between people on the noticeboard to prove it. Add a scrawled note on the bottom of the message saying "and , FatShaft42, you are one SICK Bastard! I'll be passing *your* messages onto HR!!" for maximum effect.
You are in a twisty maze of processor lines, all alike.
There is a lot of hype here.
Blame Enron and other such fiasco's.
Financial institution's have to record and hold all elctronic communications for years now. The specific number of years eludes me atm.
If you think some E-mails people send are incriminating, imagine what IM's traded around an office would expose.
It's much easier to stop the people from using IM services than to try to capture/record/log/preserve it all. At least for financial institutions which theoretically could face billion dollar lawsuits.
Or not. On second thoughts perhaps not a good idea. Still, it's your call.
Now wash your hands.
Install Linux, MSN Messenger will go away rather quickly :)
I think it would be easier to lock down a linux box to prevent installations of gaim, Gabber, etc than it would be to putz around with your firewalls trying to kill MSN Messenger.
If you allow www, you can't stop all chats. You can pretend, but you can't do it. Heck, email can be used for such as well. How about making internet access a priviledge that only those have that need. Though im can be used to boost productivity too.
world was created 5 seconds before this post as it is.
I thought financial people were supposed to be more socially able than technological people. Don't your managers understand the concept of "talking to people abouth things they should and should not do during work hours?"
I now it's not generally accepted in most larger companies, but I always question bad and lazy management decisions like this one. Management is usually paid generously enough to compensate for the occasional difficult talk with a bothersome employee. Besides, talking has a lot less negative (or even positive, depending on the person doing the talking) effect on the work atmosphere and might alleviate a general feeling of "us against the managers" in employees.
You may be able to block the win32 client, but that does not stop employees from using services like http://www.wbmsn.com/ (MSN) or http://go.icq.com/ (ICQ) for their IM needs.
Alternatively, a mass block of Microsoft's IP address range(s) should help stop people being able to connect (and you'll also kill hotmail, passport and a lot of other of their useless services with the same stone).
I used group policy software distribution to force the install of Windows Messenger on all computers. Windows Messenger is a slightly different version than MSN Messenger but it can also connect to the IM system of Exchange. We use that in house as our instant messaging system.
When once installed you can use Group Policies to lock the Windows messenger down. With registry keys embedded in the policies you can disable file transfer, video chat and even outside communications (to the internet, not intranet) of the client.
We disabled file transfer to avoid viruses slipping in via this way.
If I am correct you can even set Windows messenger to have priority on MSN messenger, thus disabling the MSN version. In this way you should have full control over the IM system. Check the knowledge base and technet for the necessary info. If necessary, contact me.
Disable via the registry with login scripts
8 1/
/ Gr oup%20Policy%20Registry%20Editor.htm
http://www.winguides.com/registry/display.php/9
Or group policy
http://www.subvers.com/technobabble/html/tweaks
If you have wildcat machines that people just setup on their own, you have a larger problem.
Conformity is the jailer of freedom and enemy of growth. -JFK
I did this with my old company. They had a very strict firewall policy, and to get a port open, you had to get through higer management.
Geez. Try baking the sysadmin some cookies, give him a case of Guiness/Bawlz, or take the poor guy to lunch.
I block MSMessenger without any problems with the following rules:
ipchains -A input -p TCP -b --sport 1863 -j DENY
ipchains -A input -b -d 64.4.13.0/24 -j DENY
now the extremely persistant Yahoo IM is something I still haven't nailed down yet.....
In this case being a finance institution, they have to log all conversations or possibly face fines.
In 99% of normal businesses, its NOT needed to have outside IM access, peroid.. If you need IM communication between your employees, great, then you use a secure internal IM setup, with no outside server access.. For people outside the firwall like sales guys, they vpn back in.
Its not in best business interest to let you talk to your wife, or friend down the street about where to go for lunch. Regardless of what you might think.
Phones the same, many dont get outside line access. Its ONLY Internal calls that they can make, unless they have a business case to get 'out'.
---- Booth was a patriot ----
LOL, that reminded me of this gem from Dilbert newsletter #43:
I like sysadmins that run Windows shops and think that since they are the only ones that know what they set the Administrator password to, their machines can't be modified. They're funny.
Anyone who thinks I'm going to work on Windows without cygwin, JSPager, xemacs, etc, has another think coming. Sysadmins are *support* personnel. They're there to facilitate work getting done. They aren't supervisors of said personnel, and controlling behavior is certainly not in their baliwick unless expressly handed down by management.
That said, I've had grand old times with IT folks who don't feel the need to try to be assholes.
Finally, I don't use any form of instant messaging at work, because I find email and phone to be more convenient. But I *have* done software development before with another person on the other end of an ICQ connection, and if that's the most convenient way to do work, IT should definitely not be trying to be a pain in the ass about it.
May we never see th
Ding Ding Ding! Correct, IT is there to HELP. Same exact thing goes with contractors, they are there to help the full time employees. As a contractor in IT departments, I can tell you that companies, contractors and IT departments are often very broken in how they try to get stuff done.
:).
NOT EVERYTHING IS A TECHNICAL ISSUE. Policy is as important as technology. Lazy management makes management problems (lack of control and accountability) into technical problems because they are too weak to deal with the issues on their own and want IT to do it for them.
Also, FlashDesktops is far better than JSPager