How Your Denial Of Service Attack Stateful Firewall Secures Your Safety

The definition of a denial of service attack stateful firewall includes all good firewalls, whether hardware, commercial or free firewall download.

Providing a firewall performs stateful packet inspection and monitors the state of network or computer connections to prevent Denial of Service (DoS) attacks, it is covered by this definition.

Here, we'll be taking a tour of firewalls and talking about...

  1. What do firewalls do?
  2. How firewalls secure and monitor traffic
  3. Supporting Denial Of Service Attack Stateful Firewall Articles

1. Denial Of Service Attack Stateful Firewall... What Do Firewalls Do?

A computer firewall is like a barricade or wall -- just like fire doors in a building. It is designed to keep in our personal information and to keep out intruders.

The most useful thing our firewall stops is someone else remotely logging on to our computer.

If our PC is compromised in this way, it can be turned into a zombie relay machine to send out floods of spam, or become part of Denial of Service (DoS) attacks against Web sites, such as those that occurred against Yahoo! and Amazon... and completely without the owners' knowledge.

It's estimated that millions of machines around the world have been compromised in this way.

A denial of service attack stateful firewall blocks intrusions to our computer and/or our computer network. Good software firewalls can also be configured so that only certain kinds of traffic are allowed to leave our computer or computer network.

When we're working with a single computer, then a software firewall will provide the protection we need. If we run a business and have several computers networked to a single online connection, then we'll also need a hardware or router firewall to secure our network from intrusion.

Once our denial of service attack stateful firewall is installed, it will monitor all our online connections, whether they be through a broadband, always-on connection, or a dial-up modem connection.

2. Denial Of Service Attack Stateful Firewall... How Firewalls Monitor Traffic

Hardware and software firewalls can operate differently in how they secure traffic flow to and from our computer. Let's get in touch with both of them in turn...

Denial Of Service Attack Stateful Firewall... Hardware Firewalls

Hardware firewalls have three levels of security -- NAT, SPI and VPN. Let's just explain what each of these mean...

  1. Network Address Translation (NAT) Technology, prevents crackers from seeing our network address while we're surfing the web. This is the basic level of protection we should expect from our router firewall.

    NAT technology translates the IP address of a local area network (LAN)to a different IP address for the Internet.

    Each PC on the network has a local IP address, but when the denial of service attack stateful firewall gets the data to forward to the Internet, it puts a different IP address on the transmission.

    This way, whoever receives the data transmission won't know what the actual IP address of the computer is... so, the computer is hidden and safe from malicious hackers (crackers).

  2. Stateful Packet Inspection (SPI) provides a higher degree of security.

    SPI inspects packets of information coming into our system to make sure they correspond to an outgoing request and are not an attack from a cracker. Unsolicited -— and possibly harmful -— packets are rejected.

    A firewall using SPI is also known as a denial of service attack stateful firewall.

  3. Virtual Private Network (VPN) enables a secure, encrypted Internet connection with another computer or another network. It's just as if the computer is physically connected there at the network location.

    When a data transmission leaves a local network, the data itself is not protected, unless a VPN is established.

    VPN is primarily used by businesses, such as the home office connecting to the company office, or the user on the road connecting from her laptop in the hotel room to the office.

Wireless routers have the above options for security, but they also require further security to protect the wireless transmissions. These are discussed in the article How To Maximize The Security Of The Best Wireless Router.

Denial Of Service Attack Stateful Firewall... Software Firewalls

Software firewalls, commercial or free firewall download, typically control traffic flowing in and out of the network by using one or more of,

  1. Packet filtering
  2. Outbound filtering
  3. Proxy server
  4. Stateful packet inspection

Let's take a look at and get a feel for each of these terms...

  1. Packet Filtering
    Information travels across the Internet in packets, or small chunks of data.

    If we have packet filtering enabled on our firewall, it analyses each packet against a set of filters that we've set. Think of it as a censor -- the packet filter censors information packets. Only packets that make it through the filters are forwarded to the requesting computer.

  2. Outbound Filtering
    Some firewalls only work in one direction... they examine packets our computer is receiving, not the ones it sends.

    Hostile applications such as Trojan horses, worms and viruses can use our Internet connection to send sensitive information from our PC. So, our denial of service attack stateful firewall should at least have a mechanism for filtering outbound traffic.

  3. Proxy Server
    Many businesses choose to implement proxy servers.

    With a proxy, all traffic from the Internet is sent to the proxy, so any third party watching the transmissions only sees the proxy... not the actual network or receiving computer. The computer firewall analyzes what's at the proxy and only then is it sent on to the requesting computer.

  4. Stateful Packet Inspection (SPI)
    Stateful inspection is also known as 'dynamic packet filtering'. It's a method that compares certain key parts of a packet to a database of trusted information. If the comparison yields a reasonable match, the information is allowed through. If not, it is blocked.

    One of the big benefits of stateful inspection is that it closes off ports until a connection to a specific port is requested. A software firewall using SPI is also known as a denial of service attack stateful firewall.

3. Denial Of Service Attack Stateful Firewall... Supporting Articles

  1. Free And Buy Firewalls Reviewed. Imagine what it would feel like to connect to the Internet and know you are fully protected from intruders. Well, it's within your grasp!
  2. Free Or Buy Firewalls? The Pros And Cons. There are three "types" of firewall to choose from. We can buy firewalls -- software and hardware -- or we can use a free firewall download. But which type is best for our computer?
  3. Choosing The Best Wireless Router Speed. When choosing the best wireless router, some of the speed terms and claims made by marketers can be confusing. Here, they are explained.
  4. The Best Wireless Router... How To Maximize Security. With basic security configuration, a wireless connection can be accessed by other computers and crackers in the vicinity. Learn how to ensure your router is protected.
  5. What Are The Effects Of Computer Hacking?. Explains how malicious hackers target our PCs, what the effects are and how we can protect ourselves.
  6. Is XP Firewall Safe?. The Windows firewall has a number of flaws. If you're using it, read this!


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