Software that controls what connections can be made to and from a network.

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2answers
2k views

What is the best way to restrict network access for one machine on a home LAN?

As an example, I have 3 computers on a home network: Machine A Machine B Machine C What I would like to do is isolate "Machine C", so that it cannot communicate with "A" or "B" and vice versa. It ...
4
votes
1answer
3k views

How to append netsh firewall rules, not just replace

I am using a script to set firewall rules in netsh. netsh.exe advfirewall firewall set rule name="Block External IP's" new remoteip="$($ipArray[0])" I thought that set was used so that it would ...
4
votes
3answers
3k views

How can I prove (with logging) where a port block is occurring?

How can I prove (with logging) where a port block is occurring? I've set up an FTP site on IIS (windows 7 home) and set up a rule in the Windows Firewall allowing access. The ftp site is accessible ...
4
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4answers
22k views

Using pfSense, OpenVPN Connects but Still Can't See the Network

I am having an OpenVPN issue. I have a pfSense box at home configured to allow traffic through a VPN tunnel. The client computer is Windows XP Home, behind a standard Comcast connection and a ...
4
votes
2answers
388 views

Every single application in Windows 7 (even these not using internet at all, like notepad.exe) trying to access internet

After some recent AV/FW software update (Comodo) and restarting my computer, I was alarmed with big amount of warnings that application "x" (where "x" is pretty much all of what I try to run) try to ...
4
votes
2answers
721 views

Would there be any problems with DEP turned off?

I recently moved to a fresh Windows 8 x64 system and I learned that my favourite firewall (JPF - Jetico Personal Firewall) doesn't get along with Win8x64 (CRITICAL_STRUCTURE_CORRUPTION errors), but I ...
4
votes
3answers
333 views

What security changes are necessary when connecting DSL modem directly to PC instead of router?

Windows XP I have a user with a single PC that was connected to the internet via a standard home router. The router is now having hardware-related issues and to save money, they're considering ...
4
votes
1answer
40k views

Windows XP Wifi connected but can not access Internet with browser

I have two laptops: Windows Vista laptop which connects fine to Internet (writing this post from it now) Windows XP SP2 laptop which connects fine to Wifi, Router but not Internet When I try to ...
4
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1answer
455 views

Program to block an IP temporarily with iptables

Is there a program on Debian to block an IP address temporarily just by launching a command (specifying the IP and the duration)? With iptables/ip6tables alone I can create a rule, but I would then ...
4
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2answers
6k views

Detect what outgoing ports are bypassed by firewall

My school has a firewall which limits most outgoing ports. There're only TCP/80, TCP/443, TCP/21 allowed. Is there's a way to find out all the outgoing port allowed by the firewall? My current idea: ...
4
votes
1answer
76 views

Is password required for restricted database servers [closed]

I have a dedicated Database server which is have PostgreSQL 9.1. This server has firewall. Only 10.0.0.3 is allowed to connect and access to this server via Firewall. All other requests from other ip'...
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3answers
3k views

Mac OS X's firewall asks: allow the application “master” network access?

In OS X 10.6.5, the following dialogue popped up: What is this application? What does it do? Cheers! EDIT (to increase googlability): OS X firewall: Do you want the application "master" to accept ...
4
votes
1answer
874 views

Safely share a printer in my local network

I have a Windows 7 PC with an attached laser. I want to share the printer over my network, which includes a Wifi router. How can I do this safely without allowing outside traffic to get into it? It's ...
4
votes
2answers
1k views

Losing 1/3 of my download speed with my new router, any ideas on how to fix?

I recently replaced a dying D-Link router with a Cisco/Linksys RSV4000. I'm really happy with the device but it seems when my cable modem is plugged in to it I lose 1/3 of my download speed. When I ...
4
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1answer
408 views

Intermittent connection and “Firewall Blocked” log entries on Cisco DPC3939B with firewall “disabled”

First, I apologize if this question seems to be "all over the place". I've tried to sum it up as clearly as I could, but there are a lot of moving parts, so I've tried to be detailed with my ...
4
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2answers
3k views

Fedora 20 FirewallD GUI not working on X11 forwarding

I am having a problem with SSH X11 forwarding on Fedora 20 with firewall-config, the GUI tool for FirewallD (the dynamic firewall system). With most X11 GUI applications including pretty much all "...
4
votes
2answers
7k views

Cannot connect to my mac via SSH

I want to open a connection to my mac (10.8) via SSH. An SSH-server is installed by default on OSX. Remote login is enabled, so the service is running and I can connect to to localhost via ssh. ...
4
votes
1answer
459 views

How to block a program from using IPv4?

I have a program that can communicate over IPv4 (TCP and UDP) and over IPv6 (TCP and UDP). I want to block the program from being able to use IPv4. I tried the Windows Firewall: Except it blocks ...
4
votes
1answer
349 views

Hints on diagnosing performance issue in OpenBSD firewall

My OpenBSD 4.6 pf firewall has started having really bad performance in the past few weeks. I've isolated the firewall (as opposed to the WAN connection, switch, cable, etc.) as the problem, but need ...
4
votes
5answers
9k views

Bridge between Wired and Wireless networks for a single device?

EDIT 18/05/2011: Thanks for your answers, bridge mode IS the solution in most cases for this problem, but I can't use it because it breaks my web server. I am now looking at setting up a specific ...
4
votes
0answers
280 views

pf error - “No ALTQ support in the kernel”… What does this mean?

I am running Mac OS X. I would like to be able to configure pf because it seems to be more sophisticated and flexible than the default Mac OS X firewall that you can access through the System ...
4
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3answers
1k views

If you block an .exe file in Windows Firewall, are you also blocking the .dll files it uses or it needs to be done separatly?

Let's consider this scenario: There's some X software downloaded from the internet with one .exe file and several .dll files. The .exe file is prevented from accessing the Internet by using Windows ...
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votes
4answers
18k views

Windows 7 is blocking ports

I am trying to open port 80 and 3690 for HTTP and svnserve respectively (inbound for both). I have Windows Firewall off, and have tried temporarily disabling Mcafee VirusScan Enterprise, to no avail. ...
3
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12answers
570 views

Is my computer security suite good enough? [closed]

I have a Windows machine and I run AVG free antivirus, Windows Defender and firewall, Spybot Search & Destroy, Outpost Firewall, and Prevx. I am just checking because I think I might have turned ...
3
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3answers
4k views

Which Linux-based firewall supports IPv6? [closed]

Out of the box neither IPCop nor ipfire support IPv6, not even on the green interface (internal LAN). How do I add IPv6 support to one of them? If that's not possible, is there a linux-based embedded ...
3
votes
4answers
979 views

How does a firewall contribute in mitigating IP spoofing attacks?

I understand that you can implement a firewall to only allow access to a server from specific IP addresses, but can't people fake the source IP address in a TCP packet? How does this actually stop ...
3
votes
1answer
1k views

How to make any IP accessible outside the network

Is it possible to make my internal IP accessible outside the network? Something like 192.168.x.xxx. If I try my external IP, I get redirected to the website of the company. I'm on Windows and I'm ...
3
votes
4answers
337 views

What is a good way to shield my computer against local (network) attacks?

I'm trying to secure my computer against local network attacks for when I'm at university or a LAN party. At home, we have a router which serves this purpose. But at university and LAN I don't have ...
3
votes
2answers
8k views

UFW is active but not enabled why?

I was trying to setup a firewall in my Ubuntu 12.04 machine. After some struggling I got the following. Isn't this sounds a bit odd? thomas@thomas-K40IJ:~$ sudo ufw status verbose Status: active ...
3
votes
2answers
7k views

How does telnet get through the windows firewall?

I activated the Telnet client in Windows 7 and was instantly able to connect to servers although Windows Firewall is activated. How does that work? Shouldn't the firewall block outgoing connections ...
3
votes
2answers
4k views

Using localhost TCP/IP communication in a program - always safe?

I have an application which is separated to several parts (processes) communicating over TCP/IP, using a pre-defined port on localhost. Is this always safe? Can some kind of a firewall (corporate, ...
3
votes
1answer
293 views

Even googling not allowed ? Why?

Access has been denied 127.0.0.1! Access to the page: http://www.google.co.in/search?hl=en&client=firefox-a&hs=F58&rls=org.mozilla%3Aen-US%3Aofficial&q=email+us&meta=&aq=...
3
votes
2answers
542 views

how do torrent clients circumvent router's firewall?

Could anyone please explain me how the deluge torrent client can get incoming requests to my local machine from the Internet, while I'm behind router's firewall and do not have any port forwarding etc....
3
votes
2answers
12k views

How to access NodeJS server on LAN?

I'm not the most knowledgeable guy ever with networking, but here goes... I've created an application with NodeJS and I'd like to test the application on my LAN with my family. The application ...
3
votes
5answers
15k views

iptables: Allow only HTTP access for web browsing

Have a linux box, want it locked down but just be able to surf internet on it. Why is this script blocking http too? #!/bin/sh # # iptables -F # #Set default policies for INPUT, FORWARD and OUTPUT ...
3
votes
2answers
13k views

OSX Lion, open a local port so people on my network can access it

I'm running django's simple HTTP server (using python manage.py runserver). It's currently running on port 8000. How can I open a port on my macbook and allow network traffic to visit my host on ...
3
votes
2answers
10k views

How to isolate WLAN clients in OpenWRT?

I'm currently setting up a public wireless network. I want to prevent the clients from talking to each other. Here's my current setup. /etc/config/firewall without anything related to lan: config ...
3
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2answers
4k views

Windows cannot find the host name “download.microsoft.com” using DNS

When trying to download a file found on the Microsoft downloads center that starts with, for example, http://download.microsoft.com/download/6/8/7/(some_GUID)/(some_file_name.ext) i get a timeout with ...
3
votes
3answers
5k views

How do I get the Windows 7 Firewall to prompt me whether to allow or deny a new connection? [duplicate]

Possible Duplicate: How can I configure the Windows 7 firewall to prompt me on outbound traffic? In Vista and before, new programs attempting an ingoing or outgoing connection would cause a ...
3
votes
3answers
740 views

Vyatta Firewall structure and Interface Direction

I've just purchased a Ubiquity EdgeRouter ER-8, and I'm working on configuring the firewall. In particular I'm confused about the direction "Local" for the interface I've defined as the WAN, and how I ...
3
votes
3answers
239 views

Creating a secure LAN within an insecure LAN

I have multiple computers on an insecure network (with third party, untrusted computers). My computers and the third party computers are all behind the same firewall. Currently my computer's software ...
3
votes
1answer
656 views

I want uTorrent to use one ISP, and all other applications to use another ISP

I have a Windows 7 based desktop with two LAN cards (NICs): NIC1 is connected to a router, which connects to a reliable ISP with a low data cap (Fair Usage Policy). NIC2 is connected to an ADSL ...
3
votes
1answer
600 views

How to setup firewall ports via logon script

I work as IT suport for public service. We use domain controller and logon scripts. These scripts are pretty helpful, since they can automatically install printers and add network folders as local ...
3
votes
3answers
9k views

Windows firewall blocks remote desktop with custom port

I was able to use my remote desktop with custom port when I was using Kaspersky Internet Security. Now, I have uninstalled my Kaspersky and switch to Avast!. Therefore, the windows firewall is turned ...
3
votes
1answer
3k views

How to find CIDR subnet for a public Internet IP address?

Usually I do not worry about subnet of an IP address on the public Internet, but after I began using Amazon EC2 firewall, it got me thinking. EC2 firewall configuration requires an IP to be written ...
3
votes
1answer
1k views

Although my firewall is off, I cannot connect so some ports on my mac (Mountain Lion)

I have a mac-mini (Fall 2009) with OS X 10.8.4 on my local network and I am running a simple http server on port 5000 (or any other port). I have turned the firewall OFF. I can connect to the mac via ...
3
votes
1answer
2k views

Deny ping response in ipv6

I would like to know how to deny ping replies on my ipv6 address. We have been messing around with ping flooding on ipv6 at work, and the usual way to block icmp requests does not work. I have tried ...
3
votes
2answers
1k views

ISP blocks the use of ssh?

I fail to use ssh connecting to my remote machine, the detail situation is as following: The remote machine is behind a firewall, but can be connected using ssh with port 45992. I used to connect to ...
3
votes
1answer
2k views

Can my firewall block web-based emails?

I am not receiving emails in my hotmail account from one particular address. (They're not being filtered out as junk mail, before you ask) I have been given the suggestion that they are being blocked ...
3
votes
4answers
2k views

How to whitelist an IPv6 address in VPC security groups on AWS?

I cannot enter an IPv6 address in the inbound rules in AWS VPC security group settings. It says The source must be a valid CIDR (e.g. 0.0.0.0/0) or the ID of another security group and It wont let ...