Question

How does a firewall work? How does internet security work? How do I ensure that I am browsing the internet safely i.e. None of my data (including usernames and passwords) is compromised to peepers?

Answer 1

What you ask for is very complex. Basically:

A Firewall closes the ports of your Computer and controlls the ones, which are open for (e.g.) internet access or games. Some firewalls go deeper and protect more and have sandbox-systems.

Internet security - thats even more difficult to explain. When you browse around, you use a specific protocol - http (hyper text transport protocol). Mostly text like this gets permitted without any encryption, but for example usernames and passwords get encrypted with various encryption-methods (which are all based on extreme high and complex math formulas and algorithms).

If you don't want your file to be ripped just don't download anything from websites which you don't know and don't use always the same password (e.g.: i have right now over ten various passwords for different logins for work, home, email, social network, ...).

Answer 2

It's also a good idea to have a password that's hard to guess. If it contains special characters, even better. The more obscure the password, the harder it is to guess. But for the most part, keeping your data secure depends heavily on your own behavior. If you frequent coffee shops and busy places, it's best not to be sending around any sensitive data without using something like a VPN.

Answer 3

There is no strict rule and regulation that defines exact service of a firewall. Generally, firewalls provide a broad range of security, including but not limited to network traffic monitoring (via packet sniffing), port monitoring, memory access protection (Win32 API Interception) etc. Basically memory access protection will detect DLL and/or code injection etc.

Working of a firewall is very complex. Basically you need low level packet sniffing, and hooking ability to monitor netowrk traffic etc.

Answer 4

So, I think that NeThWa's answer above was the most helpful here.

I would add that it's important to distinguish between the two types of firewalls as well. Most routers, for example, implement an iptables-based firewall with some stateful goodness to make things like NAT and UPnP function. This type of firewall is designed to protect you from the internet. If you're concerned about software running on your computer behaving badly you can install an Application Firewall such as ZoneAlarm for Windows or LittleSnitch for Mac. These can do two things. They can protect the internet from you (if you get pwnd by a botnet) and protect you from trojans (because you have to give every program explicit access to access the outside world).

If you want to ensure that you don't have traffic intercepted on public networks, your best bet is to ensure that 1) your home network is using WPA2, as WPA2 networks are near impossible to crack and very difficult to sniff traffic from other users on and 2) ensure that any sites containing sensitive information you're accessing from public, unencrypted wifi uses some sort of end-to-end encryption (such as HTTPS).

Additionally, use different passwords for different kinds of services. I use different passwords for services that don't use SSL (like OpenStudy) compared to those that do (like my email). This means if my password is intercepted, the amount of damage someone could do is limited to the access my account as on the site which, while expansive, is a lot less damaging than it could be.

Of course, if anyone ever gets a rootkit and keylogger on my machine, I'm just as hosed as anyone else would be.

Answer 5

As @farmdawgnation said about firewalls, I totally agree with that. If your question was explicity based on securing your system through firewalls, then I would suggest 2 things

1)You are the most safest on linux than compared to any other os
2)Keyloggers and trojans can be put to stop with help of firewalls but there are some really smart malware and trojans whihc disable your firewall and antivirus itself and hence you are really "not safe"on windows even if you have a firewall?antivirus

Answer 6

tyvm for the suggested applications. would I need a ZoneAlarm/LittleSnitch on a linux machine?

So if i'm going to be doing my ebay on those public unsecured networks, I guess I will need to learn to setup and use a vpn. How does a vpn protect my data?

Also, how would i know if my machine was a zombie and was compromised to a botnet?

Answer 7

First of all, I am typing this comment from a linux system.

Trust me linux does not require any 3rd party antivirus or a firewall because the fundamentals of linux and its security is so very strong. For all the tasks you perform at admin level, you require a password(which you have chosen at time of installation of os). There are very strict laws pertaining to changing of system files. 3rd, to perform any admin task you need to type sudo , your task name and your password


On your 2nd question, I need to do some research


On your 3rd question, I would say it is pretty easy to find out. Have a check at outgoing connections from your computer by typing ipconfig in run box of windows(if my memory serves me right) 2nd, always have a look at your antivirus/firewall and see that it is active. #rd, check for unknown processes running via you task manager. 4th, type msconfig in your run box in windows and check for unknown startup applications. 5th,Make sure you reguraly scan your system for virus/trojan/malware

All the above headache you have to take can be avoided by linux but there are certain cons about linux which you should know
1)very few Windows applications are compatible in Linux(via Windows Emulator)
2)not the OS for windows gamers

Well, all your programs for windows can easily run by installing windows on Virtualbox in linux.

So, I am not a windows gamer, so linux is the right choice for me.

Answer 8

I don't use any antivirus or security applications on my Windows 7 machine beyond what is already provided by Windows 7 (security essentials, firewall). Although this would be fine on a GNU/Linux machine (the free antivirus you can optionally download in most distros, clamav, is more suited to scanning windows files that pass through your machine :) very handy), I'm worried this would cause me some trouble someday. I use a secure browser like IE9 to browse the web. I do not run as root, and always think before clicking yes when UAC (the windows version of sudo that doesn't prompt for the password) pops up.

Should I be worried?

I dont like using dedicated AV software on windows; they tend to act like malware, aways popping up and hogging system resources.

Answer 9

@agdgdgdgwngo , In my view, Security essentials is the best antivirus. But still, the best ain't enough. My friend's computer got affected with a serious trojan even though he uses Microsoft security essentials and updated it regularly. So If you are not a pirate user and not clicking on any stupid ad links(something like install screensaver software,smilie software, etc) you are fine. But however, spam mails are another concern. Moreover you may be vulnerable which spread through pendrives. Also I want to point out that windows firewall is not that good. There is still a room for exploits to come through. So at the end I would say that always use linux for safety and best browsing experience. In linux , you save about 100 -200 mb of your memory usage which is hogged by MSE.

And yes, don't use any other antivirus than Microsoft security Essentials .

Anyways, I would suggest you experience linux at large and decide what is good for you. Linux/windows. If you are going for a linux distribution, go for ubuntu or linux mint.they are the best out there at the moment.

Answer 10

My laptop has archlinux installed on it. It's a great distro, but it doesn't come automatically configured for everything like ubuntu 12.04 (another great distro where everything works).

Is the default linux configuration secure enough, or do I need to check some things and stuff before my browsing experience is bulletproof?

Answer 11

LOL, Trust me. Defalult linux configuration is best for bullet proof security. Moved from windows 2-3 years ago to linux and enjoying the new unrattled os without any problems until today :)

Answer 12

@agdgdgdgwngo , but still that doesnot prevent you from spam emails . And be careful about giving your personal details to any unknown site :)

Answer 13

Right; I use http://tenminutemail.com and similar services when sites ask me for an email.

Answer 14

oops it's actually http://10minutemail.com

Answer 15

:D Good talking to @agdgdgdgwngo . Have a nice day :)