A firewall is a piece of software that controls what connections can be made to and from a network.

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53
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3answers
3k views

How can I turn off internet for roommates that haven't paid the bill this month?

I have several roommates who split my internet bill with me each month. On occasion they forget to pay me, and I have to pester them for the money. If after 3 days of pestering they still haven't ...
48
votes
7answers
26k views

Why does the Mac OS X firewall dialog recurringly pop-up and disappear by itself (without letting me respond) under Snow Leopard?

From time to time, I'll be on my Macbook using a program that accesses the network – whether Firefox, or Sony's Reader Library – really, it seems like it could happen with any program that ...
31
votes
5answers
18k views

How can I configure the Windows 7 firewall to prompt me on outbound traffic?

Can I configure the built-in firewall in Windows 7 to ask me if I want to let a program open an outbound connection? I can disable all outgoing traffic and manually create rules for programs, but I ...
20
votes
4answers
224k views

How can I block a program from accessing the Internet? [duplicate]

I really want to know how can I prevent a program to connect to Internet with Windows 7 firewall? I have smart security nod32 business edition installed on my computer. should i do this job with ...
18
votes
7answers
17k views

“iTunes.app” to accept incoming network connections?

Every time I open iTunes I get the the following warning: Do you want the application "iTunes.app" to accept incoming network connections? Clicking Deny may limit the application's behavior. ...
18
votes
4answers
67k views

What are Inbound and Outbound Rules for Windows Firewall?

Can anybody explain what are the inbound and outbound rules regarding Windows Firewall? What is their significance? Are they useful even when Windows Firewall is off?
16
votes
5answers
10k views

SSH access to office host behind NAT router

I would like to access the ssh port of my office linux host from home. Unfortunately the host is located behind a NAT router. So, the IP address is not publicly available. There is however access to ...
16
votes
6answers
65k views

What's the closest equivalent of Little Snitch (Mac program) on Windows?

I'm using Windows 7 and would like to have a feature like Little Snitch on the Mac that alerts you whenever a program on your computer makes an outgoing connection. Description of Little Snitch from ...
16
votes
2answers
27k views

How to block all traffic but one IP in Windows Firewall?

I'm trying to use Windows 7 firewall to block all outgoing and incoming traffic, from all IP's and for all protocals, except for UDP to and from one particular IP address. The reason why is because ...
14
votes
6answers
21k views

Changing network type from Unidentified network to Private network on an OpenVPN connection

Is it possible to change the connection type in Windows 7? I have a OpenVPN connection which is identified as "unidentified network" and I do not want to apply certain rules to all unidentified ...
14
votes
3answers
2k views

How to setup a work -> home -> internet http tunneling service

I want to know which program is recommended in order to setup such as scenario, i.e. accessing the Internet from work or other places where traffic is monitored by installing a HTTP tunneling service ...
13
votes
4answers
10k views

With Linux iptables, is it possible to log the process/command name that initiates an outbound connection?

I would like to keep track of the processes that initiate outbound connections on a Linux desktop. The best I can come up with is this: iptables -A OUTPUT -m state --state NEW -j LOG --log-uid This ...
12
votes
7answers
136k views

How to bypass web URL filtering service to access blocked websites (proxy)

I'm using network, where services such as Gmail or any other e-mails, Google Drive, Dropbox, all social networks are blocked. Basically my goal is to access simply GMail, but I couldn't find any way ...
12
votes
6answers
5k views

Does the Virtual PC XP Mode need safety measures?

Does the Virtual PC XP-Mode (or any other virtualized mode) require safety measures, such as antivirus or a firewall? I'm just wondering if the XP-Mode would be a large security loophole, since it's ...
11
votes
7answers
42k views

Apache Server on Windows 7 opening up ports?

I have installed Apache 2.2.14 on Windows 7 and can view my web pages using both http://localhost and http://127.0.0.1 but when I try to access the server from another computer on the same router, it ...
10
votes
4answers
21k views

Which ports to open for Microsoft SQL Server?

Having searched the internet a few times on the best way to open up SQL Server connectivity through windows firewall i've yet to find a best way of doing it. Does anyone have a guaranteed way of ...
8
votes
7answers
2k views

Do I really need a firewall?

I've been using the Nod32 security suite for some time now, and out of all the others that I've tried, it's great (low memory footprint, fast, fairly cheap). However, I've been installing a lot of ...
8
votes
4answers
4k views

Is the firewall in the wireless router enough?

I got an ADSL internet connection that goes into a Linksys wireless router that features a built-in firewall. Are those kinds of firewalls typically good enough for regular use, or should look into ...
8
votes
3answers
8k views

Google Chrome being blocked by company firewall

Yesterday I could use Google Chrome at work to access the internet and today it is being blocked by the firewall with an access denied error. IE and Firefox work fine from the same machine. Is there a ...
8
votes
4answers
11k views

How do I block all outgoing ports in Windows XP firewall?

The built-in Windows firewall seems to only block incoming ports, but not any outgoing traffic. I am looking for an application to install on an xp machine which can be configured a way to block ...
8
votes
4answers
3k views

If I use an SSH tunnel to get around a firewall, what does the sysadmin see?

I use an SSH tunnel for the port my browser uses to access the internet. The result is I get around the firewall my network uses, which prevents me from using many sites I want to use (facebook, ...
8
votes
4answers
26k views

How to prevent a file from accessing the internet?

There are some .exe and .dll files belonging to some programs on my laptop which communicate with the internet without my permission (for self-update generally). I want to prevent those files one by ...
8
votes
4answers
8k views

Windows tool to find out which port an app is trying to use?

I am guessing that netstat shows apps and their ports that already have a connection and it doesn't show or can't show an app that is trying to open a connection. If I have an app that's trying to ...
7
votes
4answers
1k views

Is the Windows XP firewall good enough?

I used to use a third-party firewall like ZoneAlarm and some others whose names I forget, but their complexity ended up annoying me. Assuming one runs his computer as a normal user/powersuser, is it ...
7
votes
4answers
3k views

Do I need a third party firewall for Windows 7?

I have always used third party firewalls (Zone Alarm) to avert attacks and to prevent installed softwares (like Adobe Updater) from connecting to internet. Unfortunately, when I migrated to Windows ...
7
votes
4answers
1k views

Parental control or outbound firewall?

Based on the Age distribution of Stack Overflow users some of you might also have kids in the ages when certain images can be very disturbing. An age when they cannot yet decide by themselves what ...
7
votes
3answers
1k views

Is Windows Firewall / Antivirus good? [closed]

I was wondering if I should let Windows Firewall and Antivirus take care of my system's health. Should I consider buying a paid version of another antivirus/firewall (Norton, AVG)?
7
votes
3answers
2k views

Mac firewall blocking nginx (port 80) from external side

I installed nginx using ports and started it with sudo. Accessing the nginx welcome page from localhost works perfectly, however accessing it from an external computer fails. Doing an nmap on the ...
6
votes
6answers
2k views

Is it safe to put a Mac directly on the internet?

In the past I have always run a NAT router between my Windows PC's and the internet. I'm wondering if I still need this or whether the OSX firewall is good enough to let me put a Mac directly on the ...
6
votes
3answers
274 views

Do I need a software firewall?

I have a router, that has built in hardware firewall capabilities, do I need to install an additional software firewall on my Windows 7 PC like ZoneAlarm?
6
votes
2answers
27k views

need iptables rule to accept all incoming traffic

For my test environment i want to accept all incoming traffic, can someone please give me the iptable rule to be added. My current iptables -L -n output looks like this Chain INPUT (policy ...
6
votes
2answers
8k views

How to open file and printer shares to the internet?

i tried to make file and printer sharing open to the internet on NT3.51 in 1998, but it just refused to actually ever work. Are are the IP ports and protocols that must be port-forwarded to make file ...
6
votes
3answers
330 views

Redirect ALL web traffic through TLS without a VPN

Assumptions: Server: I have a Debian Squeeze server, routable on the public Internet, with a static IPv4 address. I have unrestricted access to modify the software on the server. The server can ...
6
votes
1answer
1k views

Create firewall “profiles” for Windows 7 [duplicate]

Possible Duplicate: Limiting network connections to specific sites when travelling / tethered (in windows) Is there any way to configure a couple of firewall profiles in Windows 7? As I ...
6
votes
2answers
3k views

VPN/Tunneling (SSH or otherwise) on Windows via HTTP proxy

Situation. ... +-- Computers (to the internet) | | - [ router / firewall ] -- [ switch ] +- [ switch ] -+-- ...
6
votes
2answers
2k views

How can I set up a webserver behind two routers?

I realise that this may be better suited to ServerFault, but this is my home network that I run in a non-professional enviroment. At home I have my main router connected to the internet which the ...
6
votes
2answers
259 views

Open up firewall automatically to anybody who has successfully connected via SSH

I have a server which runs a few services. However, for security reasons, I configured the server so that nothing, except for SSH, is accessible from outside. What I'd like to do instead, though, is ...
6
votes
2answers
2k views

SSH Tunnel doesn't work in China

Last year I was working in China for a few months. I never bothered setting up a real VPN, but just created a SSH tunnel, and changed my browsers proxy settings to connect through it. Everything ...
5
votes
3answers
3k views

Is it recommended to run a firewall/router on a virtual machine?

Googling found me people saying running a firewall/router as a virtual machine is "dangerous" but none of them gives any reason as to why it is so. I also found posts from people who are successfully ...
5
votes
8answers
2k views

Outgrowing Linksys WRT54G router

Looks like the WRT54G is no longer adequate for our needs. At first with only a 2-3 people on the router it was ok, but now with more people and devices it's just no longer reliable. Crashes almost ...
5
votes
7answers
14k views

Utility to open TCP port to listen state

Is there some basic utility to open a specific network TCP port on my machine? I need to test how my program deals with ports on listening state..
5
votes
1answer
462 views

How did Google get on my Mac?

Am running a MacBook Pro, and have never installed Chrome, Google Earth, or anything blatantly Google. Just installed Little Snitch (are there no good free firewalls for Mac?) and see that CURL is ...
5
votes
2answers
219 views

What alternatives exist for Zone Alarm?

I like having Zone Alarm to warn me when programs are trying to phone home / request for updates etc. However, I feel its interface is a little clunky and was wondering if there are any alternatives ...
5
votes
3answers
582 views

Safe access to my home network subversion repository

I have a subversion server setup on my home network (windows). I'd like to open a port in my router/firewall and allow access to it from the net. What do I need to do to make sure I don't put both ...
5
votes
2answers
11k views

How can I restrict windows 7 to only use the local subnet, but block the internet

I want to block all internet connections to and from my windows 7 machine, but allow it to access everything on the local network. The local network is behind an Apple Airport Extreme. What is the ...
5
votes
3answers
23k views

Is there a simple way to detect ISP port blocking?

Is there a way to tell the difference between my ISP blocking traffic on certain ports and my NAT router/firewall blocking that traffic? The sites “Shields Up” and “Can you see me” show my ports ...
5
votes
1answer
512 views

How to easily determine, which outbound ports aren't blocked by firewall

I'm behind fairly restrictive firewall regarding ports, that can be used for connecting outside. I'm also running service on my remote box, and I want to connect to it. Problem is, that I'm unable to ...
5
votes
4answers
3k views

Tools to monitor hack attempts/port sniffing

What tools are available that allow me to monitor if someone is using a port sniffer on my computer and/or display any possible hacking attempts? I'm using OneCare, but the firewall information is ...
5
votes
8answers
15k views

Internet connection under Windows Vista stops working until reboot [closed]

I have a fairly clean Vista Home Premium SP1 install on my desktop. There aren't many applications installed. My Internet connection always seems to stop working after web surfing for a while - ...
5
votes
4answers
7k views

When the Windows Firewall Service is disabled I cannot remote desktop (RDP) to the machine

When the Windows Firewall Service is disabled I cannot remote desktop (RDP) to the machine. Has anyone seen this? This is on Win7 64 Enterprise on a domain. Is it some sort of domain policy perhaps? ...