Hacker 10 – Security Hacker

Tag: firewalls explained

  • Hardware firewall Vs. software firewall

    Hardware firewall Vs. software firewall

    Software firewalls are most suitable for home users not running a network, they are installed in the operating system and only protect that particular machine, a software firewall will screen requests going in and out of the computer and determine whether the request between the client and the source is valid by looking at the predefined rules and verify the interaction.

    For a software firewall to be effective, its configuration rules will need to be set up properly. One of the main differences between software firewalls and hardware firewalls is that software firewalls restrict Internet access by application and hardware firewalls work looking at the port and URL address.

    Software firewall advantages:

    • Cheaper than a hardware firewall
    • Easier to configure than hardware firewalls
    • You can install a software firewall on a laptop and take it with you
    • Software firewalls application filtering makes them flexible
    BitDefender Internet Security firewall
    BitDefender Internet Security firewall

    Software firewall disadvantages:

    • They don’t protect a whole network needing one copy for each computer
    • Software firewalls consume more CPU and memory resources than hardware firewalls
    • Software firewalls have less configuration options than hardware firewalls

    Hardware firewall basics

    A hardware firewalls is a device placed in between your computer and the Internet, they are harder to configure than software firewalls, the high end broadband routers can come with an embedded hardware firewall inside, these are targeted at the home user and much easier to set up than a proper hardware firewall for businesses.

    Basic hardware firewalls use packet filtering, they scan packet headers to determine their source, origin and destination addresses, and whether the incoming traffic is related to an outgoing connection, such as a request for a website, this information is compared with the preset rules that determine whether the packet should be forwarded or blocked.

    The most advanced hardware firewalls can do stateful packet inspection looking into the contents of the data packet and state of the connection allowing the firewall to make decisions about packets based on context as well as the defined rules.

    Hardware firewall advantages:

    • A single hardware firewall can protect your entire network
    • They run on their own dedicated CPU and memory not taking away computer resources
    • Hardware firewalls can not be disabled by malware as easily as software firewalls can
    • A single hardware firewall can protect multiple computers not needing a license for each computer
    • Hardware firewalls still protect the computer when the operating system crashes
    Hardware firewall WatchGuard XTM 2Series
    Hardware firewall WatchGuard XTM 2Series

    Hardware firewall disadvantages:

    • A single router firewall is considerably more expensive than a license for a single software firewall
    • Hardware firewalls are more difficult to configure than software firewalls
    • Hardware firewalls need physical space where to install it and cable layout
    • A hardware firewall protecting the whole network will affect multiple computers if it fails

    What firewall to use?

    The average home user will be well protected with a software firewall, they are easier to manage and much cheaper in price than a dedicated hardware firewall. Large corporations and schools with big networks will need a hardware firewall as they are more cost effective, representing good value for money when defending a large network of computers and not having to pay licensing fees.

    When you use a firewall you still need antivirus and antispyware software installed in your computer, a firewall will protect you from intrusions while an antivirus protects you from malicious code running inside your computer.

  • How firewalls work & list of free firewalls

    How firewalls work & list of free firewalls

    Firewalls explained

    Your computer is open to attack from the moment you connect it to the Internet, even if you do not do anything with it, if the computer IP is visible on the Internet that is all that it is needed for a malicious hacker to attempt a break in.

    A firewall is designed to shield a single computer or private network through a set rules that permit legitimate communications to pass and stops non authorized connections, firewalls regulate traffic in and out of the network using packet filtering, a proxy service or stateful inspection. A good firewall will deny unauthorized incoming requests probing all of your computer ports trying to find one of them open to launch an attack.

    Companies dealing with highly confidential data, i.e. banks, implement strict firewall rules in their network  only allowing  employees access to one part of the network and stopping them from accessing sensitive areas. The most advanced firewalls have the ability to ban content based on the words used to perform a search, they also make use of updated URL blacklists containing unsuitable websites, these options are meant to stop network users from coming across inappropriate content and wasting time on non productive websites.

    Simple firewall diagram
    Simple firewall diagram

    Home users tend to use software based firewalls, this is secure enough, schools and corporations with a large computer network will use a hardware based firewallnot having to install it on each one of the computers and being able to set it up inside a dedicated IT room instead of next to the computers.

    How to Access Windows Firewall Settings

    The Windows operating system included a built in firewall starting in Windows XP, to locate Windows Vista firewall go to Start(Windows logo)>Control panel>Security>Windows firewall>Change settings

    Using Windows security control panel you can turn on and off your Windows firewall which is activated by default unless you change the setting during the operating system installation. The Windows built-in firewall is very basic and it lacks advanced configuration in comparison to third party software firewall packages, Windows firewall will only protect you from  attacks coming from the outside, if a trojan manages to lodge in your computer and wants to send data from inside your computer to the outside world, Windows firewall will not warn you of the nasty outgoing connection.

    To update Windows firewall you need to go to Start>All programs>Windows update, the Windows firewall updates itself using Windows update, it does not have any special update button.

    Windows built-in firewall settings
    Windows built-in firewall settings

    If you install a second software firewall in your computer you should disable Windows built-in firewall, as their traffic filtering rules may conflict with each other, most software firewall will automatically disable Windows firewall during installation.

    Most popular free firewalls

    • Comodo firewall: Comodo firewall is available for download as a standalone program or bundled with Comodo Internet Security Suite, the later providing antivirus and anti-malware protection too. Comodo Firewall will cross-references any new software you download with a whitelist of over 15 million trusted files and applications.
    • Online Armor free firewall: It prevents and removes spyware, very easy to use without too many annoying popups, Online Armor guards itself and other software from tampering by third party applications and it dettects keyloggers.
    • ZoneAlarm firewall: This free firewall will resist malware attacks, its SmartDefence Advisor reduces the number of pop ups you get, comes with automatic Wi-Fi security setting activation, antiphishing protection, a toolbar, 2GB of online free storage, an antivirus and parental controls.