To better decide, it is beneficial to talk about what a firewall does. The firewall is a computing device whose sole purpose is to monitor and filter traffic. Internet communication is a process not unlike a major highway system. When you enter a address into your browser, your computer sends a signal along a network route (numbered by a port number) to another computer (described by an IP address). The port number can be between 1 and 65535, while the IP address is four numbers each between 0 and 255. The firewall will note the port and IP of each request, and based upon a set of rules the firewall will either allow or block the request. At the minimum, it will record the numbers of traffic going either way, giving a log of traffic for later review.

The difference between a hardware and software firewall arises from where the firewall sits and the mechanism it works with. A hardware firewall is a separate computing device which sits between the computer and the outside world. When the computer sends a request and the outside world replies, the firewall will review and log the request before it passes the firewall. A software firewall sits on the computer being protected reviewing all requests on the software level. Both work to protect the computer from threats entering the computer, and an infection sending data into the outside world.

The hardware firewall has the benefit of separating your computer from the process. It will review the traffic before it reaches the computer. This extends a protection that the software does not possess. The hardware firewall also has the benefit of its own resources. The firewall can also hold intelligence, filtering packets by not only where it said they came from, but where they actually came from, and their contents to an extent. The hardware firewall can also protect a number of computers on the network, as multiple computers can be on the computer side.

The shortcoming of the hardware firewall is that it does not look as hard at outgoing traffic. This can be a big problem, as some malicious programs could transmit data or launch attacks from your computer. Also, if too many computers are on the network, then the firewall will get bogged down with traffic requests, slowing the entire network down.

Software firewalls work on the individual computer. The user can choose specific programs to allow sending traffic to the outside world, and the protocol for other programs. It can be configured to deny everything but what is listed on a safe list, or it can prompt you to decide of you want to keep the site on the safe list. The big problem with the software filter is that it will only protect the computer it is on. As a result, if there are a number of computers on the network, each will need its own firewall, making it more complex to setup the network.

The question of which is better is a challenging one. Each has its own strengths. The hardware firewall is good at blocking direct intrusions and any incoming malicious code. The software firewall is better at identifying Trojans and email viruses trying to turn your computer into a zombie terminal (one that launches denial of service attacks or spam messages).

The minimum amount of protection that should be had is a hardware firewall. Upgrades and additions to your computer and its network will not affect your network security and firewall. To boost the protection, supplanting the hardware firewall with the addition of a software firewall will give a near complete protection passage. No protection is perfect; so long as there is an internet connection, then there is a possibility for someone who is highly skilled getting into your computer. The addition of firewalls will deter most attackers and block automatic, malicious scripts.

When the Internet first started, it consists mostly of static web pages, where people can upload and share information as texts. As technology advances, and hardware and software become more advanced, the Internet began to evolve into one of the most amazing and effective communication in the entire world. Compared to the television, the Internet has seen growth that’s three times as fast as the television networks. But that’s hardly surprising, considering the possibilities of what can be done on the Internet.

Before long, most people figured out that the Internet is an ideal place for communications. It is, in fact, conducive to share information in any format on the Internet, such as video files, text files, and audio files. So people started to use the Internet to connect with everyone else, even if the person on the other end of the line is halfway across the globe. On the Internet, that is not a problem at all. And soon, the need to connect and communicate grew so strong that innovative web developers started to launch social websites like Friendster, MySpace, and now the immensely popular Facebook.

These social networks, also commonly known as social communities or Web 2.0 websites, allow web visitors to register at the site and instantly network with other members of the site. But then, there are privacy concerns. What if a member doesn’t wish to be contacted by strangers? What if a member simply doesn’t want to be interrupted with a flood of online messages? For sure, if nothing is done about privacy issues, the website will lose its portion of its audience. Web visitors like their privacy to be respected. So social networking sites recognize this need, and has come up with special features so that members can block other members from contacting or messaging them.

But being at the technological fore-front does attract attention from all types of different people. And some of these people are just as technically inclined as the developers of the website. They invented a way to get around the blocking system, and they call this solution web proxies. Using web proxies, they are able to “cheat” the system into believing that they are really a different person. Hence, the website is unable to recognize them and therefore, cannot block them. By using web proxies, members can now surf social networking sites while remaining anonymous. That means it’s going to be difficult to trace their footprints. What is essentially happening is that the user is accessing a website through a third party server, and the website recognizes the server as a user. In a way, it’s something like “hiding” behind a server while accessing the sites.

If you are interested in pursuing more knowledge on this subject, feel free to check out some of the web proxies available out there.

A report last year by Internet security company Barracuda Networks indicated that just over 50% of its customers used the company’s products to block employee access to MySpace, Facebook, or both. What’s unfortunate is that companies are turning to security vendors to solve what is most likely a productivity issue, or may be no issue at all.

The latest social network to spill over the corporate firewall is Yammer, winner of the best of show award at this year’s TechCrunch50 event. Yammer describes itself as “a tool for making companies and organizations more productive through the exchange of short frequent answers to one simple question: ‘What are you working on?’” It is similar in function to Twitter or Facebook status updates. According to TechCrunch, “There is such a huge demand for this type of service that 10,000 people and 2,000 organizations signed up for the service the first day it launched.”

According to a report earlier this year by Comscore, “The number of worldwide visitors to social networking sites has grown 34 percent in the past year to 530 million.” In some regions, such as the UK, social networking sites account for more than 75% of all web traffic. Clearly, the social networking phenomenon is here to stay. It is how people like to communicate online. So why expect that to change when employees start their work day?

With the possible exception of pornography and documented security risks, employee access to external Internet sites, or any kind of information, should be controlled with policy and education, not technology. Employees know when they are being blocked, and they can’t help but feel that the company doesn’t trust them. Most companies have very clear policies on what content employees can and cannot view on company time, and, download, store, share or access on their company-owned computers. In many cases they have granted the company the right to monitor their Internet traffic to assure compliance, and the company can enforce these policies with verbal and written warnings, disciplinary actions and termination if it so chooses.

IBM, for example, has a very well thought out Social Computing Policy that, instead of banning access to social networks, informs employees, suppliers and others as to what the company views as appropriate use. Is it surprising that a “traditional” company, established in 1896, has such a progressive outlook on social media? Or maybe that gives us a clue as to how the company has adapted and survived for over 100 years.

Attempts to shield employees from “harmful” information are nothing new. One Fortune 500 company discouraged employees from viewing the company’s quarterly earnings web cast because, according to one communications VP, “the executives might say something that would upset the employees.” (This policy was also no doubt intended to improve productivity, and to limit bandwidth headaches when the company’s sizeable workforce all attempted to watch the web cast simultaneously.)

In another situation, a large IT company decided to provide streaming video coverage of a product launch, which could not be viewed inside the company, because its IT organization routinely blocked all streaming video, regardless of its source.

The net result of all of this can be a knee-jerk IT response that keeps people from communicating with others in the ways they find most useful and engaging. All of the fun, and with it most of the incentive, has been sucked out of internal communications in many companies. Yes, of course, there are productivity issues and people do indeed often spend far too much of their time on social networks like Facebook, MySpace, and Twitter. And some people are truly addicted to them.

Some companies are responding by saying “we’re not here to have fun — if it was fun they wouldn’t call it work.” Other more forward-looking, and more pragmatic companies have come to recognize that human nature is what it is, and companies need to create communications tools that engage, and stimulate employee adoption and usage, not because it is mandated, but because it is useful and enjoyable.

Recognizing this, many companies are introducing internal “clones” of popular social networks, like Pfizer Pharmaceutical’s Pfacebook, and IBM’s Twitter clone, BlueTwit. Still other companies have found even more creative ways to make communications something employees like to do, by using streaming video, internal blogs, and even communications tools with simple video gaming capability built in as a “hook” to engage employees.

So which strategy is most effective? If you block all external social network access with technology, it will feel like the problem has been dealt with, and from an administrative standpoint, maybe it has. But there may be fallout, such as employee discontent, and in time, there will be hacks and new applications to get around corporate IT blocks. Ultimately, it comes down to policy, education, and how you choose to empower (or not) a trusted, adult workforce.

It’s still too early to say that companies that don’t embrace social media “don’t get it,” but it is clear that allowing access to social networks within a framework of trust and appropriate use will free valuable resources for better use, and will improve employee morale and productivity.

Proxy sites help to bypass filters created by network administrators at your school or work place, these are in place to stop students or employees from accessing websites which are not supposed to be accessed mainly due to the irrelevancy that they have with your job or education.

There are different types of proxy servers which can be created some which use the server its self to put a server request through without contacting the specified server.

Other proxy sites use the World Wide Web this being the most common type of proxy site the “web proxy” these are used as a web cache providing access to blacklisted websites.

Proxy sites also help to allow banned IP addresses that may have been blacklisted from certain websites filtered access back in to that website.

You can create your own proxy site very easily with basic knowledge of HTML and CSS as well as a slight knowledge of PHP. Proxy sites offer you access to every website that may have been blocked before, you are able to surf and chat also giving you the choice to surf youtube and watching videos. Proxy sites are often slower than entering the website from the normal route due to the bypassing they have to do however they are generally fast enough.

Some of the programs that get installed on your computer, such as the free P2P programs that allow you to share music or movies, are generally referred to as Adware or Spyware programs, because they gather information about you such as your geographical location, what websites you visit, maybe your age and gender, and then target advertisements to you based on that information. Some of the more insidious programs will go so far as to capture credit card numbers, Social Security Numbers, birthdates and account numbers and try to transmit this information back to a Server computer.

Ideally, you would want a firewall that not only blocks connections from the Internet, but would also notify you if a program already on your computer is trying to connect to the Internet. Some of the programs installed would of course have a valid reason for trying to connect to the Internet, such as an antivirus program that needs to connect to a Server to download the latest definitions in order to keep your computer safe from the latest types of infections. You may also have an Operating System that would need to connect to the manufacturer’s Servers to download the latest security fixes or patches.

There is a wide selection of firewalls available for consumers, both hardware and software based. Do as much research as you can and check with respectable sources and which product or suite of products would best fit your needs. My personal recommendation is to stay away from small and un-established companies, and instead use one of the major company’s that are recognized as an authority. For example, Symantec and Network Associates are both well know companies for their Norton and McAfee products. For hardware, you may look at Linksys or Netgear as they have created solid products for use with the average everyday consumer. Again, these are just examples of personal taste, so do as much research as possible to determine which solution would fit your needs, if you are a home owner with a wireless laptop or WAN administrator with 1,500 computers to protect.

So that is the platform, now let us consider what the problem of having such a vast resource is. Those belonging to the blogging world must be aware of the do follow movement, where in blogs remove the “no follow” tag from their sites so that the bots from Google can even record the links of the homepages of the people who comment.

Now where do proxies come into the picture here, well there is no doubt where it comes in, it lets people comment from different proxies!  So even if an admin wants to ban a particular IP for commenting too much or commenting for monetary gain, the person could use a proxy and still post a comment. Thus again creating the head ache for the admin to delete it. So web proxies score.

Distorting proxies are not much of a problem; it is the anonymous proxies that can be the real irritant. Well the admin can always delete the comment but then there is the effort and time quotient here. Web proxies thus are something that SEO people and other opportunist use to the hilt and with great success. There are people who sitting in the US, who comment from a Saudi Arabian IP.

Well guess web proxies will never go away and the only thing that can be done spam filters be made more efficient and better equipped.

To understand this exploit, you must first understand about Google’s Duplicate Content filter. It’s simply described thus: Google doesn’t want you to search for “blue widget” and have the top 10 search terms returned copies of the same article on how great blue widgets are. They want to give you ONE copy of the Great Blue Widget article, and 9 other different results, just on the off chance that you’ve already read that article and the other results are actually what you wanted.

To handle this, every time Google spiders and indexes a page, it checks it to see if it’s already got a page that is predominantly the same, a duplicate page if you will. Exactly how Google works this out, nobody knows exactly, but it is going to be a combination of some or all of: page text length, page title, headings, keyword densities, checking exactly copy sentence fragments etc. As a result of this duplicate content filter, a whole industry has grown up around trying to get round the filter, just search for “spin article”.

Getting back to the story here, Google indexes a page and lets say it fails it’s duplicate content check, what does Google do? These days, it dumps that duplicate page in Google’s Supplemental Index. What, you didn’t know that Google have 2 indexes? Well they do: the main one, and supplemental one. 2 things are important here: Google will always return results from their Main index if they can; and they will only go to the Supplemental index if they don’t get enough joy from their main index. What this means is that if your page is in the supplemental index, it’s almost certain that you will never show up in the Search Engine Ranking Pages, unless there is next to no competition for the phrase that was searched for.

This all seems pretty reasonable to me, so what’s the problem? Well there’s another little step I haven’t mentioned yet. What happens if someone copies your page, let’s say your homepage of your business website, and when Google indexes that copy, it correctly determines that it’s a duplicate. Now Google knows about 2 pages that it knows are duplicates, it has to decide which to dump in the supplemental index, and which to keep in the main one. That’s pretty obvious right? But how does Google know which is the original and which is the copy? They don’t. Sure they have some clever algorithms to work it out, but even if they are 99% accurate, that leaves a lot of problems for that 1% of times they can get it wrong!

And this is the heart of the exploit, if someone copies your websites homepage say, and manages to convince Google that *their* page is the original, your homepage will get tossed into the supplemental index, never to see the light of day in the Search Engine Ranking Pages again. In case I’m not being clear enough, that’s bad! But wait, it gets worse:

It’s fair to say that in the case of a person physically copying your page and hosting it, you can often get them to take it down through the use of copyright lawyers, and cease and desist letters to ISP’s and the like, with a quick “Reinclusion Request” to Google. But recently there’s a new threat that’s a whole lot harder to stop: the use of publicly accessible Proxy websites. (If you don’t know what a Proxy is, it’s basically a way of making the web run faster by caching content more local to your internet destination. In principle they are generally a good thing.)

There are many such web proxies out there, and I won’t list any here, however I will describe the process: they send out spiders (much like Google’s) and they spider your page, take your content, then they host a copy of your website on their proxy site, nominally so that when their users request your page, they can serve up their local copy quickly rather than having to retrieve if off your server. The big issue is that Google can sometimes decide that the proxy copy of your web page is the original, and yours is not.

Worse again, there’s some evidence that people are deliberately and maliciously using proxy servers to cache copies of web pages, then using normal (white and black hat) Search Engine Optimization (SEO) techniques to make those proxy pages rank in the search engine, increasing the likelihood that your legitimate page will be the one dumped by the search engines’ duplicate content filters. Danger Will Robinson!

Even worse still, some of the proxy spiders actively spoof their origins so that you don’t realise that it’s a spider from a proxy, as they pretend to be a Googlebot for example, or from Yahoo. This is why the major search engines actively publish guidelines on how to identify and validate their own spiders.

Now for the big question, how can you defend against this? There are several possible solutions, depending on you web hosting technology and technical competence:

Option 1 – If you are running Apache and PHP on your server, you can set the webhost up to check for search engine spiders that purport to be from the main search engines, and using php and the .htaccess file, you can block proxies from other sources. However this only works for proxies that are playing by the rules and identifying themselves correctly.

Option 2 – If you are using MS Windows and IIS on your server, or if you are on a shared hosting solution that doesn’t give you the ability to do anything clever, it’s an awful lot harder and you should take the advice of a professional on how to defend yourself from this kind of attack.

Option 3 – This is current the best solution available, and applies if you are running a PHP or ASP based website: you set ALL pages robot meta tags to noindex and nofollow, then you implement a PHP or ASP script on each page that checks for valid spiders from the major search engines, and if so, resets the robot meta tags to index and follow. The important distinction here is that it’s easier to validate a real spider, and to discount a spider that’s trying to spoof you, because the major search engines publish processes and procedures to do this, including IP lookups and the like.

So, stay aware, stay knowledgeable, and stay protected. And if you see that you’ve suddenly been dumped from the Search Engine Rankings Pages, now you might know why, how and what to do about it.

The Cisco IOS Firewall Feature Set is a module that can be added to the existing IOS to provide firewall functionality without the need for hardware upgrades. There are two components to the Cisco IOS Firewall Feature Set in Intrusion Detection (which is an optional bolt-on) and Context-Based Access Control (CBAC). CBAC maintains a state table for all of the outbound connections on a Cisco router by inspecting tcp and udp connections at layer seven of the OSI model and populating the table accordingly. When return traffic is received on the external interface it is compared against the state table to see if the connection was originally established from within the internal network, and then either permitted or denied. Although basic this is a very effective mechanism to prevent unauthorized access to the internal network from external sources such as the internet.

CBAC Application-specific support

Cisco have also built in some additional functionality into CBAC in terms of application-specific inspection that enables the router to recognize and identify application specific data flows such as HTTP, SMTP, TFTP, and FTP. Understanding these applications and their data flows empowers the router to identify malformed packets or suspect application data flows and permit or deny accordingly. CBAC also provides the flexibility of downloading Java code from trusted sites, but it denying untrusted sites.

CBAC and Denial of Service (DOS) Attacks

Denial-Of-Service (DOS) attack protection is also in-built with real-time logging of alerts as well as pro-active responses to mitigate the threat. To do this CBAC can be configured to manage half-open TCP connections which are used in TCP SYN flood attacks to overload a targets resources resulting in a denial of service to legitimate users. To do this CBAC uses timeouts and thresholds, which are configurable, to determine how long state information for each connection should be kept for sessions and when to drop them. Note that UDP and ICMP require that an idle-timer limit is used to determine when a connection should be terminated. A very useful command to identify a DOS attack is ‘ip inspect audit-trail’ which logs all DOS connections including source and destination IP address and TCP or UDP ports allowing you to pin-point the exact source and destination of the attack.

Configuring CBAC

There are five steps to configuring CBAC on a Cisco router in order for it to function correctly. These are as follows:
1. Choose an interface to which inspection will be applied. This can be an internal or external interface as CBAC is only concerned with the direction of the first packet initiating the connection which is identified when applying CBAC to an interface.
2. Configure an IP access list in the correct direction on the selected interface to allow traffic through for CBAC to inspect.
3. Configure global timeouts and thresholds for established connections or sessions.
4. Define an inspection rule specifying exactly which protocols will be inspected by CBAC.
5. Apply the inspection rule to the interface in the correct direction.

Web proxy servers are generally classified into four groups: Transparent, Anonymous, Distorting, and High Anonymity. Transparent proxies identify themselves as a proxy server and also makes the original IP address available through the http headers. Anonymous proxies identify themselves as a proxy server but does not disclose the original IP address. Distorting proxies identify themselves as a proxy server, but make an incorrect original IP address available through the http headers. High Anonymity proxies do not identify themselves are proxy servers and do not reveal the original IP address.

When it comes to security the bottom line is to be wary when using proxy servers, and only use proxy servers of known integrity (e.g., the owner is known and trusted, has a clear privacy policy, etc.), and never use proxy servers of unknown integrity. If there is no choice but to use unknown proxy servers, do not pass any private information (unless it is properly encrypted) through the proxy.

This happens by hiding their IP address so that they cannot be traced. Every device and computer connected to the Internet has a unique identifier called an IP address which enables accurate communication and identification across the World Wide Web. People that prey on Internet using can use their address to trace the persons browsing habits and allow them to obtain important information which should not be in other persons hands.

Employers will use the IP address of company computers, along with various other methods, to track employees Internet habits while at work. The debate of privacy comes into play here but the law will normally take the employers side here. Because of these issues, more and more people have turned to proxy surf HTTP proxies to enable them to protect their privacy in their surfing habits online.

HTTP proxies allow a person to surf the Internet anonymously, acting as a middle man between the users computer and the Internet. The user can visit any website they want to under the disguise of a anonymous IP address. A HTTP proxy can keep prying eyes off the Internet users web surfing habits. They also have the advantage of being compatible with any type of browser.

However, a HTTP proxy is not always secure and therefore have their disadvantages. Some are left open, either by poor management or just malicious intent. Open HTTP proxies can expose the user to problems like piracy attempts and manners of fraud.

A web based proxy is usually safer to use and can be neatly as efficient as HTTP proxies, but do have their drawbacks. A web proxy can be slow and can contain errors in the display information and cal also crash while the user is browsing. Some are better than others so research and experimentation is needed to find a reliable one that will cater for the users needs.

Proxy site networks is another option available to ensure that web browsing is secure, anonymous, and reliable, though they too have potential drawbacks in inter-networks administration, bandwidth issues, and availability. There is a growing demand for anonymous web browsing and it will only increase so more options are continuing to become available.

However, for every advance in anonymous web browsing, there is a counter advance in Internet espionage. Never assume that the Internet is an anonymous place because it is not. Only if you take certain steps disused in this article can you then minimize the likelihood of prying eyes and other problems.