Firewalls | Computer Networking Tips

Secure Your Computer With Firewall Now

On 02.24.10, In Firewalls, By admin

Jonsan Parker asked:

With the Internet become a common hang out place for nasty viruses, spyware and other perilous matter, you can’t take your computer’s security for granted. Such a situation pushes a need for PC security products like computer firewall. The basic function of firewall protection is to prevent unauthorized access to a network. A network can include your local area network, wide area network, and the Internet or it can simply be an Internet Service Provider (ISP) trying to prevent unacceptable access to the files.

Computer users who are run actually run an effective firewall product need to be well versed with the basics of windows firewall and how to use it.

However, they can come across some common problems while using Windows Firewall. These errors usually include inability to configure firewall, trouble in accessing games, Web or other server. Such irritating issues can only be fixed with the help of professional computer technicians holding good technical knowledge and armed with right tools.

In addition to helping you with fixing issues with Windows Firewall, computer technicians can also get you the installation and configuration of your computer security products done. Some consumers underestimate the importance of configuring their firewall program. It is however significant to access the Internet. Most times, you may require changing your configuration setting to enjoy your audio applications properly. A properly configured Windows Firewall system is must for all businesses no matter small or large.

An increase in need for technical solutions is actually leading to the ongoing buzz about windows Firewall support Computer users are engaged in offering such services have a vast array of resources to troubleshoot firewall errors, design and execute a perfect firewall structure as per your personal as well as business requirements. You may also consider Windows Firewall which come bundles with some of Microsoft Operating Systems like Windows XP and Windows 2000.

Windows firewall holds immense importance for corporate and serves as a core of a secure computing and networking environment. Technicians working with computer support companies are trained on the latest security technologies to deal with existing problems and threats on regular basis.

Best Firewall for Your Laptop

On 02.22.10, In Firewalls, By admin

Victor Pradel asked:

While you are thinking anything for you laptop you must be highly sensitive towards it. Being the most sophisticated machine any minor harm can lead to a big trouble for you. And if it is out of warranty period then it is gone. So always keep a good eye on your laptop. Now having the best firewall especially for you laptop is a tough one to be carried about. As being the portable machines it comes in the interference of many networks and depending upon your usage you always try to change the network so in order to have a full protection from the hacker as well as much harmful script which comes to your laptop while being online one must have a good firewall installed on your Laptop. So be very careful while you are using different networks to connect yourself to the internet.

The other thing you can do is to have a nice firewall installed on your Laptop which continuously monitors your outgoing and incoming packets on the network and warns you for every suspicious bit transferred from your laptop in or out of the system. There are many of them available from freeware to shareware. The most popular among the Freeware category is the Comodo Firewall which has the largest efficiency of blocking all the suspicious traffic from the system.

In fact many of the freeware as we know are buggy but Comodo has excelled for those. Also many of the Antivirus software also come with firewall preinstalled in them but they are not very much efficient enough to stop the suspicious script. So always try to have a good Firewall along with good Antivirus software installed on your Laptop so as to make your Laptop free from any hacker attack.

Tagged with: Antivirus Software • Good Eye • Laptop • Warranty • Warranty Period

What is a Firewall ?

On 02.22.10, In Firewalls, By admin

Benjamin Hargis asked:

Simply put it acts as a barrier between your computer and the internet. To protect you from crackers, hackers and malware.

If your running DSL or a cable modem you should employ a firewall, as having a direct connection to the Internet can make you a target to attack.

Firewalls can be hardware or software based. With firewalls you set up ACL’s or Access Control lists to allow or deny traffic.

There are three different ways a firewall can block traffic.

1. Packet Filtering- Packets are analyzed against filters in the firewall rulesets. Firewalls will drop packets that are not allowed in the firewall rulesets.

2. Proxy Service- Information from the Internet is grabbed by the firewall and delivered to the requesting service thru the proxy.

3. Statefull packet inspection- looks up criteria against a database of trusted information. To see if the packet contains anything that would allow

or deny it into the network.

Firewalls are customizable allowing you to create your own rulesets you can block IP addresses, specific protocols such as Telnet, FTP, ICMP, UDP, SMTP and
many others.

Firewalls can be customized to block specific ports, or even keywords.

There are many software firewalls availiable such as Tiny Firewall http://www.tinysoftware.com/home/tiny2?la=EN That is designed to keep hackers out of your network and block Spyware.

Zone Labs makes ZoneAlarm I like it bcause it has a simple interface allowing home users to configure it easily. http://www.zonelabs.com/store/content/home.jsp

For hardware firewalls there is:

Cisco http://www.cisco.com There brand is called PIX firewall.

From home users I like D-Link DI-604 this is a inexpensive firewall that works well. Best of all it fits into almost any budget.

Linksys (now part of Cisco) offers a router/firewall that supports VPN and DMZ.
http://www.linksys.com

There are many hardware solutions including setting up a firewall on a *nix box. I like this the best as it gives you the firewall administrator the most control. I personally like OpenBSD for any security applications I would run with Unix, as it is secure. There have been very few exploits against this platform.

I will be writing more articles about firewalls shortly.

Tagged with: Access Control • Firewall Rulesets • Packet Filtering • Ports • Requesting Service

Firewall Protection – Why You Need It?

On 02.21.10, In Firewalls, By admin

Mark P asked:

If your house has an alarm system, surveillance cameras, or any type of security equipment to prevent burglars, then you can compare it to a firewall. A firewall will monitor and limit connections to your computer from the internet and other users. A computer without a firewall is defenseless, and makes it easier for hackers or unwanted programs to invade your computer. There are two types of firewalls, hardware or software.

Routers are devices that act as hardware firewalls. They prevent other users and unwanted software from entering your network. Routers are not only great for firewalls, but also can be used for sharing and connecting computers to a network. Some people use Network Address Translation (NAT) routers as firewalls, even though NAT routers primary purpose is to share an internet connection with local computers. If you do not have a router firewall, you can use a software firewall that will do the job.

There are many software firewalls out there, but only a few are free. Most of the software firewalls are shareware, trials or subscription. Some free versions only have some features and if you want the full package, you will need to pay. Window XP comes with a decent firewall, but you need to make sure you have Service Pack 2 and the latest updates installed.

You can check to see if your Windows XP firewall is running by clicking Start / Control Panel / Windows Firewall, or another way is My Computer / Control Panel / Network Connections / Right click your “Local Area Network” and click properties / Click on the Advance tab then click Settings. You can click to turn your windows firewall on or off.

Software firewalls can be very complex as they contain several features. Some of the features are antivirus and antispyware, program control, e-mail protection and privacy control. These features help boost your protection for your computer, since a firewall alone cannot do everything. A disadvantage of having a software firewall instead of a hardware firewall is that it will use your computer’s resources to function. Make sure you have enough memory to prevent your system from crashing. Software firewalls can manage inbound and outbound traffic by placing policies or rules. These policies will allow or reject your programs from accessing the internet, and prevent any unwanted internet programs from invading your computer. These policies are at the owners control and may change any setting as they wish.

Firewalls may give the user increased security by protecting your computer from hackers, as opposed to having no firewall. Hackers will try anything to get into your computer by searching through your computer’s ports. Your computer has many ports. They are used to connect to the internet, but sometimes they are left open. Hackers can send a virus or spyware to these ports, and take control of your computer. To prevent this from happening, a firewall will make sure all unused ports are closed.

If you plan to access the internet without a firewall, it is like putting your hand in a beehive. The risk of you being stung are high, and it is the same risk for your computer to be hacked. Without a firewall your ports will be opened, and make it vulnerable for hackers. Therefore, choose a proper firewall that suits your needs. For more information, visit my blog PC Software Revealed for details about the recommended software to keep you computer safe.

Tagged with: Computer Control • Free Versions • Network Address Translation • Network Routers • Software Firewall

Installing a Computer Firewall

On 02.21.10, In Firewalls, By admin

Darrin Johnson asked:

With the onslaught of computer hackers, scammers, and viruses that are prevalent around the Internet, it is important to know how and why you should install a firewall. A firewall is your first line of defense between your computer and data that is entering it. Without a firewall, your computer is prone to a dangerous attacks that can wipe out your data or steal personal information that can negatively impact you.

You first need to determine what kind of firewall you need for your computer. There are many available, some from major corporations such as Microsoft. If you already have a computer that came installed with the Microsoft XP or Vista operating system, then chances are that your firewall is already set up and ready to be used. However, you do need to make sure that it is turned on and working properly. If you do not have one of these later operating systems, then you need to purchase your own firewall software. (Even with Microsoft XP, you may still want to purchase separate firewall software since the XP version doesn’t get great reviews.)

There are many firewalls products available, including as the most popular – Norton, AVG, and McAfee. You can either visit a store that sells computer software or download a firewall product through the Internet. Prices vary depending on sophistication of the software, but there are also plenty of low cost firewalls available, even from the big name companies. Once in hand and prior to installing your firewall, you need to take a few things into consideration.

Firewalls can block certain functions that you need, so you must configure it to allow those, such as file and printing sharing. You will normally learn how to do this during the installation or by using its documentation to change the settings once the firewall is installed.

Firewalls tend to stop you from going to certain parts of the Internet as well. This can happen if you use a local area network or a router, so it is important that you are familiar with how you connect. Secured networks in particular are difficult to access with a firewall in place. If you work from home or connect to a company computer, you need to coordinate with the IT department in your company before installing a firewall since they may have specific instructions concerning how to configure its settings so you are still able to connect to them.

Tagged with: Computer Firewall • Network Router • Onslaught • Sophistication • Viruses

Firewalls For Peace of Mind

On 02.20.10, In Firewalls, By admin

Sandy Cosser asked:

When I first heard about firewalls I imagined a wall of fire surrounding my computer, protecting it from all the nastiness that permeates the web. It has since been brought to my attention that the obvious comparison is with a fire break, a sort of demilitarised zone that stops fires from spreading.

Firewalls act as a permeable space between your computer and the rest of the net. They deny undesirable items entry while allowing network friendly ones to pass unhindered. I think that I prefer my vision of evil transmissions going up in flames while the righteous enter unharmed.

Firewalls function according to rule sets that can be specified and customised according your business’s needs. Rule sets can be either inclusive or exclusive. Exclusive firewalls block only the traffic that has been specified in the rule set; all other traffic is allowed through. Inclusive firewalls on the other hand, only allow through the traffic that matches the rule sets and block all other transmissions. Inclusive firewalls offer more security than the exclusive kind.

Firewall controls traffic through the use of one of three methods:

• Packet filtering: filters analyse chunks of data to see if they match the rule sets. If the packets of data meet the set specifications they are forwarded to a requesting system. Packets that fail to make the grade are summarily discarded.

• Proxy service: In this method, the firewall retrieves information directly from the Internet before it’s forwarded to the requesting system.

• Stateful inspection: A relatively new method that singles out key aspects of data packets and compares them to information that is stored in a database. The method is based on an analysis of information sent from the business. If incoming information matches the type of content going out, it’s allowed in.

You can customise firewalls by adding or removing filters according to criteria that’s relevant to your business. Some examples of features that can be customised include:

• IP adresses: filters can block traffic transfers to and from certain IP addresses if they suspect them of foul play or malicious intentions.

• Domain names: Access to and from certain domain names can be blocked by the same process that blocks IP addresses.

• Protocols: According to howstuffworks.com, protocols are the pre-defined ways in which people or computer programmes talk to services that they want to use. Firewalls can be set for the following protocols:

Internet Protocol (IP)

Internet Control Message Protocol (ICMP)

Hyper Text Transfer Protocol (HTTP)

Simple Network Management Protocol (SNMP)

Transmission Control Protocol TCP)

It’s possible for businesses to set up protocols on only a few of their computers while blocking them on the rest. In this way it’s possible for the business to retain complete control of information entering and leaving their networks. They can also restrict their employees’ access to certain kinds of network sites and capabilities.

However you imagine them, be it as fiery walls consuming Internet evil, or as the more traditional protective permeable space between your computer and the rest of the net, there is no denying their extreme importance. With hackers and e-vandals using the net as their personal playgrounds, it’s more essential than ever to protect your assests, particularly valuable data. It’s no longer a quesiton of should you get a firewall, but which firewall is best for you?

Recommended sites:

http://www.howstuffworks.com/firewall.htm

http://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/firewalls.html

Tagged with: Break • Data Packets • Fires • Traffic • Wall Of Fire

UTM Firewalls (Unified Threat Management) and the Benefits for Corporate Networks

On 02.19.10, In Firewalls, By admin

Victoria M. Brown asked:

Unified Threat Management was originally designed to help protect the networks of small and medium sized businesses, but recently UTM firewalls have been expanding to corporate networks as well. The term UTM is used to describe network firewalls that contain many different features in 1 box.

Such features include e-mail spam filtering, an intrusion prevention system, anti-virus capability, internet filtering, and the functions of a traditional firewall. Basically, what this means is that a UTM firewall can perform the same functions in 1 box that would otherwise require 2 or 3 boxes.

What are the benefits of UTM Firewalls?

1. The main benefit of Unified Threat Management is the fact that so many necessary functions are combined into one box. This reduces the complexity of the firewall system and saves businesses time and money.

2. Since all the security features are in one device, you do not need to spend time figuring out how all your security devices work and then how they all work together. Once you understand how your UTM firewall works, you understand your entire security system.

3. Also, because the whole security system is in one device, there is much less to buy. In fact, the only thing that you have to buy is the UTM firewall. This significantly reduces the cost that needs to be spent on a security system.

4. Maintaining network security can often become complex and confusing, but when all the security features are combined into one system, it is easy to see how all the functions are integrated and how they work together. Also, because it is only one system coming from one vendor, training for the entire system also only comes from one vendor. This means that when you need help, there will only be one company you need to go to. This is much easier than having to contact three or four different companies if the system fails.

The ease that is created by Unified Threat Management as well as the time and money that the system saves makes it a worthwhile investment for any business. If you need to protect your network, get started with a UTM firewall today.

Tagged with: E Mail • Entire System • Firewall System • Time And Money • Vendor Training

Design of an Ideal Personal Firewall

On 02.19.10, In Firewalls, By admin

David Matousek asked:

Common concept

This paragraph describes common concept of Windows personal firewalls. It is not necessary to implement the firewall in a similar way to have it secure. Common personal firewall is implemented as three or four separate components.

Kernel driver

The first part is kernel driver. Its has two main functions and that is why it is sometimes implemented in two components rather than in one. The first function is a packet filter. Usually on the NDIS, TDI or both levels this driver checks every packet that comes in from the network or goes out to the network. This is also known as inbound and outbound connection protection. There exist some personal firewalls that do not implement neither inbound nor outbound connection protection. However, these products also have kernel drivers because of their second function. The second function is called sandbox. The most common methods of the sandbox implementation are SSDT hooks and SSDT GDI hooks. The driver of the firewall replaces some system functions with its own code that verifies the rights of calling application and either denies the action or passes the execution to original code. These methods allows the firewall to control all the possible dangerous activity of applications such as attempts to open files, processes, registry keys, modify firewall settings, automatically respond to its queries etc.

System service

There are special user mode processes called system services. These processes have special functions and behaviour in the system. They run under privileged system user rather than under common user account. This fact allows services to run independently of user and they run also when no user is logged in. The role of service in the personal firewall is to secure the communication between main components. The service receives messages from the GUI and from the kernel driver and forwards this messages to each other. For example if the firewall is in the learning mode, the driver code in hooked SSDT function may be unable to decide whether to allow or deny the action because there is no corresponding rule for the action in the database. In such case it wants the user to decide. This requires to send a message to GUI to show the dialog and to receive the answer from it. This communication is usually implemented through the service component. The service of the firewall is sometimes used to ensure that the GUI is always available for the user.

Graphical user interface

The graphical user interface (GUI) is the user part of the firewall. It often implements a trayicon from which the administration of the firewall is available. Another important function of the GUI is to ask user for the decision of actions when the firewall is in the learning mode.

Self-protection

This is rule no. 1 for all security products, not only for personal firewalls. No matter the perfection of other features, if the firewall is not able to secure itself it is useless. If a malicious activity is able to switch off, disable or destroy the personal firewall it is equivalent not to have any personal firewall at all. All parts of the firewall have to be protected including its processes, files, registry entries, drivers, services and other system resources and objects.

Verification of own components

The verification of own components is very close to the above mentioned Self-protection. Firewalls are usually complex programs and they are often implemented in more than one module or component. In such case there are a few main modules that are executed by the operating system. During the startup or in the middle of run these modules loads other modules of the firewall. We say that the modules are loaded dynamically. It is necessary to check the integrity of all dynamically loaded modules. This implies that the integrity checker must be implemented in one of the main modules.

Inbound and outbound protection

A good personal firewall offers both inbound and outbound protection. The inbound protection means that packets sent from the Internet or local area network to your computer are filtered and only ports that you want to be open are accessible. This protection is standard and is very good and reliable in almost all personal firewalls. On the other hand is the outbound protection which cause problems to all vendors nowadays. The outbound protection means that only applications that are allowed to can access the Internet or local area network. This is not as simple as it looks. Imagine the situation that you want to browse the Internet with your Internet browser and that you do not want other applications to do so. The problem here is that it is not enough only to check which application wants to send the packet to the Internet because modern operating systems allows programs to communicate. An application that is not allowed to access the Internet can start the browser and use it for the communication. Your personal firewall has to protect all those privileged applications against misusing by malware. It has to restrict the access them. But this is still not enough. The personal firewall has to protect itself. Malicious applications should not be able to switch it off or modify its rules. This means that it also has to protect system resources etc. There are many problems in this and we still talk only about one feature – the outbound protection.

Process protection

Every privileged process must be protected against several dangerous actions. Firstly, no malicious application can terminate the process. Secondly, it must not be possible to modify its code or data. Thirdly, it must not be possible to execute any code in a context of any privileged process. This point also includes DLL injection.

File and component protection

The protection of files is very close to Process protection. If a malicious code is able to replace files of privileged applications it is equivalent to modify their code flow when they run. There are two ways how to implement the protection of files. The first way (active protection) is to prevent write and delete access to files that belong to privileged applications. Because this can be hard to implement many firewall coders choose the second way – to check the integrity of modules (component protection). In this case the firewall allows malicious code to damage or replace files of privileged applications. If such application is about to run its modules are verified and the execution is stopped or reported to the user. The file protection is also needed for all system files.

Driver protection

Windows operating systems trust its drivers. This mean that every code that is run by the driver is trusted and thus it is allowed to execute even protected processor’s instruction and has potential access to all system resources. This is why it is necessary to implement a part of security software like personal firewall as a system driver. However, it is also why it is necessary to control loading of new drivers and to protect existing drivers. Malicious programs must not be able to install drivers or modify already loaded drivers.

Service protection

Since a part of the firewall is usually implemented as a system service the protection of system services is also necessary. But it is not only the firewall component that has to be protected. To install a new service is easy way for malware how to persist in the system because system services can be set to run every system start. What is more, a malicious service can be dangerous also because it runs even if no user is logged on. Creation, deletion and control of system services must be protected actions.

Registry protection

Windows registry contains a lot of important system information. Settings of system components can be changed using the registry. An incorrect modification of some registry objects can easily cause system to become unstable or unable to boot. There are many registry keys and values that should be protected against modifications of malicious applications.

Protection of other system resources

There are also different system resources and objects in Windows operating systems. Some of them can be dangerous if they are controlled by malware. One of these objects is a well known section ‘DevicePhysicalMemory’ which can be used to gain the complete control of the system if it is not protected. The firewall must protect those objects that can be misused by malware.

Parent process control

We already know that it is necessary to protect privileged processes. Probably the easiest way how to implement process protection is to control opening of processes and threads. However, if the process protection is implement in this way it is also important to implement Parent process control. Every process in the system has to be created by some other process – its parent. The parent is always given two handles when new it creates child process. These are handle to the process object and handle to its main thread. The given process handle is opened with a full access and thus the parent process can control its child completely. This is why the firewall must restrict the execution of privileged processes. Moreover, the parent process control should be implemented even if the firewall security design does not protect processes via control of opening of processes and threads. Some privileged processes can be misused to execute privilege action if they are run with specific command line arguments. Many firewalls do not distinguish between the execution of privileged and unprivileged processes. They restrict the process creation in general such that only those applications that were selected before are able to create child processes.

Control of automatically started programs

The firewall should protect those places in the operating system that can be used by malware to persist in the system after the reboot. If we allow users to run new unknown applications then there is no chance to protect the system against executing malicious application. And users often download and install or run new applications. The firewall is able to restrict actions of malicious applications such that they are not able to damage the system. However, if the malware application persists in the system it can damage it later when a new security bug is discovered. This is why the firewall should control those applications that are run automatically e.g. after every system start or user logon.

Sniffing protection

Spyware like keyloggers or packet sniffers are dangerous applications because they are made to steal the most sensitive data users can have – their passwords. But not only passwords are targets of these applications. Personal information, personal correspondence or business documents are also sensitive information that must be protected. The firewall has to protect sensitive data not only when they are complete in form of files but also when they are made or being transferred. Keyloggers can receive every key stroke user makes and thus assemble the whole information letter by letter. Packet sniffers are waiting for the messages to be transferred using some network interface and they make copies of sent messages. There are many ways how to implement spyware programs to collect sensitive data and all of them have to be protected by the firewall.

Protection of system resources

Every system has limited resources. Windows workstations are able to deal with a few thousands of objects. This number is sufficient for every work of common users. However, if a malicious program creates thousands of threads the system become unusable and such an action cause Denial of service (DoS). The firewall should limit unprivileged applications to cause DoS. There should be a limit set for number of threads, open files, used memory and other system resources used by unprivileged applications.

No ring3 hooks

The ring3 (or usermode) hooking is a technique that can be use to implement a personal firewall or its parts. However, ring3 hooks can be used only for special features and never for security critical features. A protection implemented by ring3 hooks can be easily bypassed by malicious applications. Ring3 hooks must not be used to restrict behaviour of unknown applications. They can be used very rarely to modify or control the behaviour of privileged applications that are guaranteed not to bypass ring3 hooks.

Tagged with: Hooks • Personal Firewall • Registry Keys • Special Functions • System Functions

Setting Up a Firewall

On 02.18.10, In Firewalls, By admin

Patrick J Smith asked:

There are two types of firewalls, hardware and software. A software firewall resides on your machine, while a hardware firewall is a standalone device that connects to your network. Both do the same thing; they attempt to stop unauthorized traffic from entering or leaving your network or your PC.

This section provides instruction for setting up a personal firewall, which is a software application that you can use to protect your computer. In my opinion, even if you’re running hardware firewall on your network every computer you own should have a personal firewall installed. There are several on the market, including a couple that are free for home use.

While a hardware firewall is useful for protecting your network from threats that originate from the Internet, many threats originate within a WLAN, from wireless attacks or access points. A hardware firewall provides no protection against wireless intruders because these attacks originate on the wrong side of the firewall. This is why I stress the use of software firewalls to protect individual computers on your WLAN.

Installation of a personal firewall is usually easy and is handled by an installer program or wizard. Exact installation instructions differ among firewall applications but there are a few common points that you should consider when installing any personal firewall.

1. Install a personal firewall after you have completed the setup of your WLAN. You want to be sure that everything is working properly before installing the firewall, so that you will know if subsequent problems are due to the firewall blocking connections or if there is a problem with the WLAN configuration.

2. Do not install more than one personal firewall on a computer. Running multiple firewalls does not make your computer more secure. The applications are likely to interfere with one another and crash your computer. They might also prevent each other from operating correctly, leaving your computer vulnerable.

3. Gather MAC and IP addresses from your WLAN clients before installing. Most personal firewalls install with a default setting that blocks all traffic from entering your computer. If you are sharing files or peripherals (printers), you need to tell your firewall which computers to let through. Depending on the firewall you are using, you need the IP or MAC addresses of computers that you want to allow accessing your PC.

Personal firewalls are highly configurable, and many block outgoing as well as incoming unauthorized connections. You may find that your firewall is “noisy” at first. This means that you may see a lot of warnings and dialog boxes as each application tries to connect. Most firewalls quickly learn which of your applications should be allowed to connect to the Internet and which shouldn’t. If you see a warning that a particular application has tried to access the Internet, do the following:

1. Determine what the application is. If you don’t know what it is or what it does, look up the application’s name through a Google search. Chances are you have a lot of spy ware on your PC that you don’t even know about. If you don’t know what an application is, don’t let it access the Internet.

2. If you know what the application is and what it does, and you feel comfortable letting it access the Internet, then configure your firewall to let it pass.

Insider insight: You are running Windows XP then you already have a firewall on your computer. Windows XP comes equipped with the Internet Connection Firewall ICR. ICF does a decent job of blocking incoming connections to your PC but does not block outgoing connections.

Once you have installed your personal firewall, test it by visiting Gibson Research Corporation’s “Shields Up!!” utility. Shields UP!! is an online utility that tests the effectiveness of your firewall.

Tagged with: Firewall Personal • Firewall Software • Individual Computers • Personal Firewall • Wizard

A Dedicated Server Firewall

On 02.18.10, In Firewalls, By admin

Adam Gufarotti asked:

One of the applications included in the management of a dedicated server is firewall protection.

A firewall is used in conjunction with a web server as a security measure. It is a function that applies a configuration that accepts or denies transfer of data in whatever form the transfer is taking place. It can encrypt or proxy all information that is travelling to and from a computer between different security domains. The dedicated server firewall is established based on a particular set of criteria that forces the moving data to adhere to specific rules.

Levels of Trust

The web server’s firewall inspects all traffic that attempts to pass through it and based on the preset criteria, determines if the data transfer may continue. The firewall is configured to variable levels of trust from which it makes its determination. Typically, the Internet is a traffic zone where the trust level is extremely low due to the fact that computer viruses and worms can be sent easily over the internet through emails and contracted by visiting websites. These viruses and worms can be extremely harmful to a computer, to the point of rendering it useless.

An internal network is considered to be on a higher trust level, since the data that is being transferred originates from an internal source, thereby lowering the likelihood of the harmful elements which can destroy documents and software programs. A traffic zone that includes data transfer involving both the internet and the intranet (internal network) is referred to as a “perimeter network” or Demilitarized zone (DMZ) and is managed by dedicated servers as an intermediate trust level.

How a Firewall Works

Picture a fire door in an office building to gain a clear understanding of the function of a firewall in a web server. In both cases, its task is to contain or delay potentially damaging factors from spreading to the rest of the facility. If a firewall is not correctly configured it can become essentially useless. The typical standard security level that is built into a firewall allows only traffic and connections that have been “explicitly allowed” but without in depth comprehension of network applications required in a specific operation the “default-allow” ruleset can be mistakenly implemented. This permits everything and anything to enter the system. Dedicated servers management covers this base – configuring the firewall for the specific needs of an organization so that there is no danger of a network system compromise.

Tagged with: Dedicated Server • Harmful Elements • Preset Criteria • Proxy • Web Server