May 31, 2008

Between Dominance and Existence

"Whenever someone exerts his supremacy beyond tolerance, the people looks for an alternative"; its a law that has existed since ages.Whether it is politics, cine field, science or internet, the law holds true.

People were furious with their search engines, they wanted more information at their hands,the players of the industry were incompetent and also ruthless, people were looking for an alternative, a Saviour who could serve their bellies with information that was valid and timely. Thats when Lary Page and Sergey Brin took the task and Google hit the scenes. Since then it has been a success story,all headlines and news papers, magazines and other media hailed Google ,not only for their efficient search engine, but because of their business ethics and user friendliness. I am sure Page and Brin knows it better than anyone. They were the ones who has shown the path of innovation to overcome competition rather than force or power. Infact Google has proven it a hell lot of times.

The result is visible, its the best search engine, also it provides a bunch of extremely good utilities.So why is Google popular?, the answer is anybody's guess. They stand with people and work for the people. But now that statement is being shaded. The latest modification of page rank algorithm has put almost 100,000 bloggers in agony, reason being the tussle between Google and Payperpost metaphorically between an elephant and an ant. Not only Payperpost ,they seem to be cracking down all publishers and advertisers who seem to be a part of what they call,"illegal link marketing".

Google is no more true to what it is known for. Infact it has transformed like every big frim does, it is the super power of internet, so when it raises eyebrows on small players of the game,naturally the spectators line up with the big gun. Maybe this would be the same fate that Payperpost suffers. Its not grown enough to challenge Google, so finally Google would emerge victorious. But as all big firms are, arrogance and domination decided the result here,but that always triggers the downfall too.

Google has grown far enough to find methods to avoid illegal manipulation of page rank by paid link posts. If they had taken any of such measures,people would have embraced it with pleasure. But what have they done, cut down the ranks of Payperpost publishers and advertisers to 0. So people would naturally move out of Payperpost( unquestionably , page rank still rules the bloggosphere) and stick with Google, not because of love with Google, but because of losing out of world's best search engine's result page. The patronism out of love and respect and out of fear stands at extremities.This page rank modification is alleged to be a step taken by Google inorder to avoid any risk to their Adsense scheme( I wonder how far that is true).

None expected 2 graduates from Stanford university to rock the world with their innovation.History can repeat,maybe there can be another such innovation that could root out the pioneer itself. But the order of the day is that Google is no longer an angel now. It has started to use its power and its assured of victory,but not to forget victory out of force doesnt remain forever. Once its dominance would be started to be hated by people, they would look for a new alternative, then their will be a new Saviour,it will take over the world and Google might face what many giants faced by Google's arrival.Probably Google is in its early stages of taking the path of dictatorship,its still loved by people including me.But it would be disheartening if it gets out in terrifying people and the babies of internet and exerts tyranny in the community.

Let Google never forget that "Whenever arrogance decide your decision , Nature rallies against you".

-Varun Krishna, a true patron of Google who feels the firm is triggering a catastrophic transformation to the antonym of its motto ("DO NO EVIL").

May 30, 2008

Google, is it right??

Google is considered as one of the angels of Internet and even I don't have a different voice. Its one of the most hailed and elite branded firms which holds customer service,satisfaction and innovation upfront better than any other firm.

But now it seems a bit of transformation is taking place, its not that they are becoming completely profit oriented, but now I feel they happen to lacking a bit of transparency in some of their services.

Google Adsense

Google Adsense is one of the very best methods to earn money if you have a very good website or blog.But the problem is your site has to be too good if you are to actually gain benefit from it. I mean to say the minimum payout is 100$. Now even if you have a very good website,only very few would be checking out the ads placed on your blog and you cant be guaranteed to reach your payout limit so easily. So actually what happens, Google keeps the money till it reaches the limit and then pays it to you. My friend had joined Adsense almost two years back and he has earned 27$, so what does that mean. Millions of such people might have earned such an amount and Google keeps it without paying any interest.Infact Google would be earning millions of dollars from such balances. There is nothing bad with Google earning money, but it is certainly bad that they are still not reducing limit or atleast giving an option for lesser limit. So what they are actually doing is making branded websites and stuff more richer,the individual websites will probably need to work a hell lot better. I have seen many switch on to BIDVERTISER and other sites which has a payout of $10, atleast people doesnt have to wait for so long.Also I have heard many countries have been removed from the list of affiliate earning( especially Asian countries). I dont think thats the right way to do it. Another big flaw being even if someone randomly clicks on the ads in your sites and creates problems,you are out of the game and you Adsense account is blocked for ever. They have a feature of filing appeals which is a mere mockery. I wonder why are they keeping such a feature when there is no provision for reactivating an account. If you are saying that you have tracker software and stuff,believe me that cannot always stop the menace. Its high time Google must reconsider their Adsense policies.

Page rank

Its been a while now I have seen people, especially bloggers run madly for link exchange, the reason: to get a handsome page rank. That has crept up many new sites,but fortunately Google has strongly acted upon such forged or cooked up links for just rank sake, But has been it been completely successful, well I really doubt it. You can see a hell lot of links to other blogs from each blog and that itself shows the desperation of a blogger. What is more disheartening is Google has decided to drop the page ranks of those blogs who has got sponsored reviews on their blogs, especially the one having a tag "Sponsored by..". I wonder what must be the cause, because it doesnt or infact will not hamper any legal violations or user privacy. If some one terms it spamming, I really dont find any logic since a blog doesnt force you to visit it,its a pull technology; I think users would better judge it a spam or not. Anyways such sponsored reviews are far better than the flashy ads and stuff . I would like to know if Google would drop ranks of the sites who put on sponsored ads from Adsense, if not ,I think it should not do this with sponsored reviews too.

Its a known fact that Google is a leader in web world, but it doesnt mean it has the monopoly over it.Internet is much an open environment and once Google would start forcing its terms, It would surely meet with the fate of many giants who had tried these tricks earlier. I am sure Google would consider this and stick to its motto "DO NO EVIL".

May 29, 2008

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The height of pessimism

Having a disbelief in certain things that you do can be justified,probably your past prompts you to feel so,but what would you say when you always feel that you have done something wrong when you almost know you haven't. Its that level of pessimism I am talking about.Wondering who is the maverick who keeps such high levels of pessimism, don't look around anywhere ,its me.

My last semester examination started from this Tuesday and as always,after the first exam,even this time I had something to worry on. It was all fine till I reached home,exam went well and I had written well,but I don't know I have this sort of thought that everything can't go that well together; that's when I put myself into thought if I had written my roll no correctly. Every time I use to check it before I give my answer sheets,this time I remember to have checked everything else other than this.Is it that I forgot to check or is it I forgot that I had checked?, what ever be the thing,my forgetfulness had eaten up a lot of hours till now,I wonder what would happen if I have written it wrongly. Now, the problem is I still keep wondering about it even though I know its of no use now. But as always,some positive things never strike my mind in time.Even today I had an exam, I feel I have written it well.I hope my mind wont again search for something to give me a head ache out of agony and tension. This is not the first time I have put myself in such weird thoughts and started thinking,I shouldn't have done it (may be something I would not have done actually.). One thing is sure,this pessimism keeps me always engaged and I dont get a moment where I feel I am bored. Probably peace of mind is something that we ought to find from within ourselves and that's the art I seem to be lacking.

May 24, 2008

An inconvenient truth


I hope you are familiar with the title.This was a documentary presented by Mr. Al Gore (the former US presidential candidate) on global warming. Even this post is regarding the same topic.

Today I came across a documentary on this issue in a news channel.It was actually a study based on the effects of global warming in Mumbai. I was really wondering about the ignorance of we people on the catastrophic effects of this menace. Mumbai is actually built on reclamated land and so the effect of global warming would be much severe. Infact the TV program displayed the effect with an example. It mentioned about a sea shore housing apartment which was actually meters away from the sea with a beautiful beach,almost 3-4 years back.But now , the sea is just feets away and there is no beach at all. The sea has taken over the land,one of the un noticed effects of global warming.It is estimated that the sea level would rise by 1 metre by the end of this decade,but its effect has begun to make its presence visible.

The most ridiculous fact is that when people were asked regarding this, some of their replies were," well its after 100 years why should I care?","by that time I would be expired,so I dont think I need to be bothered about it". This not only shows the irresponsibility,but the inertia to accept the fact and do the required.How can we ever create awareness regarding global warming when this is how people respond.

This is basically due to the ignorance that people have in this issue. Infact its not just about the rise in water level,since Mumbai is built over reclamated land and so water encroachment during high tides would be enhanced with time passing by; what happens is that the buildings and apartments at sea shores, especially the basements of these buildings would start to corrode due to salty water of the sea.So once the basements start to corrode, the whole building would come down one day with no pre-indications.The other big change,the climatic irregularities is already visible.
So its time we people be aware of the situation,its not just the people of Mumbai,but the people across the globe need to be aware of this menace. At least now, lets realise the inconvenient truth and gear up to overcome it.
courtesy:CNN-IBN

May 23, 2008

Filicide

Fil´i`cide
n.1. The act of murdering a son or a daughter; also, parent who commits such a murder.

Definition of Filicide as given in the Webster dictionary.

This is a new term that I learned today. I am happy that I could enhance my word power atleast by a bit by knowing there exists such a word in English language, but I am unhappy by the way I came to know about this word.

I had a much event less morning and noon session today,the usual sleepy session, encounter with books and the usual surfing and chatting..But again by evening,as similar to yesterday, I had a not so good news in store for me when I turned on CNN-IBN news channel.
Before getting into that ,let me narrate a very short story

The main characters are a 14 year old girl,her father and a servant of their house.The girl was said to be having a close relation with the servant (mind you,she is 14 year old).The girl's father is told to be having an extra marital affair which the daughter couldnt digest, even the servant knew it.So when the girl and the servant were discussing the issue, the father came in. He didnt like what was going on there and he took the servant to the terrace ,finished him off and later killed the girl. Finally after so many issues and controversies,the police finally arrests the culprit.

It would make a wonderful story and infact a wonderful movie in Bollywood or Hollywood whereever it is made because one would feel it could miss a bit of reality and there is lot suspense and thrill.But truth at times is stranger than fiction.I would be happy if this was just a story. But what I just narrated is a cruel reality that happened in Noida, New Delhi where a 14 year old girl was brutally murdered by her dad for reasons that itself remains as a black mark to humanity and society. I was initially happy to know that police caught the culprit of the murder case that had created much hip hop and sensation across the nation. But now it might create much more havoc as the culprit is none other than the girl's father, a filicide committed with multiple motives.

I had heard about sacrificing son or daughter to Gods as a present or gift to Gods.Even though the logic was nothing better than nonsense, even this evil practice had a justification.But what happened in Noida is something that doesnt even deserve the word justification.It was nothing new to know that culprit had an extra-marital affair,but its ridiculous that he killed his daughter because she was alleged to be having an affair with the servant.How could he ever expect her to be right when he himself was on the wrong path.I wonder how a father could kill a daughter inorder to satisfy his ego or save his status in the society.It might have a taken him a moment or two to finish her off,but its sad that he never thought of the fourteen years that he had seen of his daughter's. Now I remember the scene from the movie "Armageddon" where Bruce Willis recalls the moments ,that he shared with his daughter ,from the moment she was born to the moment when he left her.Then he presses on the nuclear trigger and the movie just proceeds.

I dont and would never understand the culprit's mentality while he was busy taking the life of her daughter. Why did he raise her up for these many years,to finish her off this way.Well this question might never be answered. But as far I know, humanity is far moving out off humans. We are more machines now and feelings mere words. I hope it would never be too late before we realise that we are far far away from what we are meant to be.

-Varun Krishna

Internet is for fun

Its been some time now that I have started the hobby of hopping across various blogs.In fact this have given me a chance to come across some wonderful blogs and here I start my new section of introducing such wonderful blogs to you.

Internet is for fun is one of the blogs that has really fascinated me.Its a blog with a simple and straight design.What is really worth mentioning is the range of the topics the blogger has managed to cover in his blog.It includes Movies, Internet, Blogs, and more, in fact a lot more.

Usually the tendency or the basic thing I have seen in many blogs is the bloggers just copy and paste or at least put on a known issue or topic in a really repetitive style or in fact a charmless manner.This is where this blog stands out, if you are asking me how, I would tell you to just visit this blog and know yourself.The style of presentation is simple,funny and straight.The most important thing is the ability of the blogger to convey the idea in a humorous manner and I can say,the author has really succeeded in his endeavor.Have a visit to Internet is for fun and experience a new pattern of blogging.Internet is for fun is really a great blogging experience.

May 22, 2008

E-com notes

Firewalls for beginners

Types of firewalls

EDI

Types of e-commerece

The matter published here has been taken from various websites and is strictly used for noncommercial and educational purpose only


Introduction
Access to e-mail and other Internet resources is very much a necessity for conducting business and accessing information. However, along with the convenience that network connectivity brings, it also raises serious security concerns. With always-on connections such as cable modems and DSL lines, Internet users need to be increasingly vigilant of security issues, as network traffic coming into the computer can cause damage to files and programs even when the user is away from the computer and the computer is idle. In a system that is not protected with any security measures, malicious code such as viruses can infect systems and cause damage that may be difficult to repair. Unscrupulous characters on the Internet are always snooping around trying to find open computers from which they can steal personal files, personal information or create other forms of mischief. The loss of financial records, e-mail, customer files, can be devastating to a business or to an individual.
In conjunction with other security measures, firewalls can help to prevent this devastation.
What are Firewalls?
Firewalls are tools that can be used to enhance the security of computers connected to a network, such as a LAN or the Internet. A firewall separates a computer from the Internet, inspecting packets of data as they arrive at either side of the firewall ? inbound to, or outbound from, your computer ? to determine whether it should be allowed to pass or be blocked.
Firewalls act as guards at the computer?s entry points (which are called ?ports?) where the computer exchanges data with other devices on the network. Firewalls ensure that packets that are requesting permission to enter the computer meet certain rules that are established by the user of the computer. Firewalls operate in two ways, by either denying or accepting all messages based on a list of designated acceptable or unacceptable sources, or by allowing or denying all messages based on a list of designated acceptable or unacceptable destination ports.
Although they sound complex, firewalls are relatively easy to install, setup and operate. This article will provide a brief introduction to firewalls. This is not intended to serve as a review of specific firewall products. Rather, it will serve as an overview of what firewalls are, how they work, the different types of firewall technology and their suitability for small office/ home office and personal computer users.
TCP/IP
In order to understand how firewalls work it is important to understand the basics of TCP/IP, the language or protocol which all computers on the internet use to communicate. If you are not at all familiar with concepts such as packets, ports and IP addresses, please refer to the "Internet for Beginners" article at LINK. If you are, the following section may seem elementary; however, it explains each of the aspects of TCP/IP as it relates specifically to firewalls.
Let?s start by saying that TCP/IP is a ?language? that allows different computers to communicate. On the Internet, this language is spoken and understood by all different types of computers, even those using different operating systems such as Windows, Macintosh, or Unix. In order for a computer to communicate on the Internet, it must ?speak? TCP/IP.
Packets
When messages are sent along the Internet, they are broken up into small ?packets? that take different routes to get to the destination. On reaching the destination, the packets are re-assembled to form the complete original message. This method is similar to writing a letter, except the sentences that make up the letter are each sent in a separate envelope. With the large number of packets travelling the Internet, it is important that the content of the packets are transferred reliably and to the correct destination computer source information in the correct order ? this is where TCP/IP comes in.
TCP/IP ensures that messages arrive at the proper computer in the proper order. Internet Protocol (IP) is used for addressing messages so they can be exchanged between the source computer and the destination computer. Transmission Control Protocol (TCP) is responsible for making sure the entire message is received in the correct format (this will be explained in more detail later in this section). These terms may seem technical but the main thing we have to remember is that TCP/IP makes information exchange over the Internet possible. And what does this have to do with firewalls? Computers identify themselves using an IP address, which is similar to a street address. The IP address is a numerical translation of the web address. For example, the IP address of www.securityfocus.com is 207.126.127.69. When the message is in packet form, the destination address and the source address information are carried in the ?head? of the packet.
The IP address is an important concept in the discussion of firewalls because firewalls read the IP addresses in the head of the packets to determine the source of message. They then use part of that information to determine whether or not the message will be allowed access or not.
Ports
We have talked about firewalls guarding the entry points of the computer system ? these entry points are known as ?ports?. Personal computers use TCP/IP ports to communicate with other computers. Simply put, a port is a point at which computers connect to networks and to other computers so that it can exchange information with networks and other computers. Personal computers have various types of ports, each of which provides a specific and unique service. Port numbers that are open indicate which applications or services that computer is currently running.
Each port has a specific number, and each one allows computers to exchange information related to a specific application. For instance, computers typically exchange information with the World Wide Web via port 80. The port number is held in the information in the packet header. This is important for firewalls, because by reading the packet the firewall can tell what application the message is trying to run. Firewalls can be configured to deny certain applications, which they determine by reading the port number of the incoming packet.
For example, one common service is FTP, or file transfer protocol, which allows computers to exchange large files of text and graphics. The FTP server on a computer utilizes port #21. If the recipient computer is open to accepting FTP packets, it will accept packets that indicate that they are FTP packets by the inclusion of port #21 in their header. If, for instance, the recipient computer is not running FTP, it would not be open to receiving information that is addressed for port #21. Thus the firewall should be configured to deny access to any packets that are destined for that port number.
Some common TCP/IP ports and their corresponding numbers are:
• FTP (File Transfer Protocol) - #21
• SMTP (Simple Mail Transfer Protocol) - #25
• Login (Login Host Protocol) - #49
• HTTP (Hypertext Transfer Protocol) - #80
• Auth (Authentication service) - #113
• Audionews (Audio news multistream) - #114
Port Scanners
Hackers often use software tools called port scanners to find services, such as the ones we just mentioned. Once the port scanner finds a service or an application that is running, the hacker then determines whether or not that specific service is vulnerable to attack. When they find vulnerable applications, the hacker may exploit them to gain entry into the system. Once inside the system, hackers proceed to attack the target and disrupt services by deleting or transferring critical files or by reading and/or stealing information that is stored on the computer.
There are 65,535 virtual ports on a typical personal computer that can be used to gain entry. The firewall has to keep an eye on each one of these ports. Talk about having a tough job!
Types of Firewalls
We can think of firewalls as being similar to a bouncer in a nightclub. Like a bouncer in a nightclub, firewalls have a set of rules, similar to a guest list or a dress code, that determines if the packet should be allowed entry. Just as the bouncer places himself at the door of the club, the firewall is located at the point of entry where data attempts to enter the computer from the Internet. But, just as different night clubs might have different rules for entry, different firewalls have different methods of inspecting packets for acceptance or rejection.
Packet Filtering
The most common firewall method is known as packet filtering. Maintaining our bouncer analogy, some bouncers may only check ID?s and compare this with the guest list before letting people in. Similarly, when a packet filter firewall receives a packet from the Internet, it checks information held in the IP Address in the header of the packet and checks it against a table of access control rules to determine whether or not the packet is acceptable.
In this case, a set of rules established by the firewall administrator serves as the guest list. These rules may specify certain actions when a particular source or destination IP address or port number is identified. For example, access to a pornographic web site can be blocked by designating the IP address of that site as a non-permitted connection (incoming or outgoing) with the users? computer. When the packet filter firewall encounters a packet from the porn site, it examines the packet. Since IP address of the porn site is contained in the header of the packet, it meets the conditions that specifically deny such a connection and the web traffic is not permitted to go through.
Although packet filters are fast, they are also relatively easy to circumvent. One method of getting around a packet filter firewall is known as IP spoofing, in which hackers adopt the IP address of a trusted source, thereby fooling the firewall into thinking that the packets from the hacker are actually from a trusted source. The second fundamental problem with packet filter firewalls is that they allow a direct connection between source and destination computers. As a result, once an initial connection has been approved by the firewall, the source computer is connected directly to the destination computer, thereby potentially exposing the destination computer and all the computers to which it is connected to attack.
Stateful Packet Inspection
A second method utilized by firewalls is known as stateful packet inspection. Stateful packet inspection is a form of super-charged packet filtering. It examines not just the headers of the packet, but also the contents, to determine more about the packet than just its source and destination information. It is called a ?stateful? packet inspection because it examines the contents of the packet to determine what the state of the communication is ? i.e. it ensures that the stated destination computer has previously requested the current communication. This is a way of ensuring that all communications are initiated by the recipient computer and are taking place only with sources that are known and trusted from previous interactions. In addition to being more rigorous in their inspection of packets, Stateful inspection firewalls also close off ports until connection to the specific port is requested. This allows an added layer of protection from the threat of port scanning.
Application-Level Proxy
Other types of bouncers have stricter rules: they not only want to know who the guest is, but what he or she will be doing once they are inside the club. In the world of firewalls, this type of bouncer is known as an application-level proxy because it determines if a connection to a requested application is permitted. Only connections for specified purposes, such as Internet access or e-mail, will be permitted. This allows system administrators to control what applications their system?s computers will be used for.
For example, hackers can use the Telnet service (which in the early days of the Internet was developed to allow remote logins to computers) to gain unauthorized access to a network. However, a firewall can be setup to allow only web and e-mail applications to gain access. The firewall can be programmed to stop all packets with the destination port of 23, which is the standard port for Telnet. Any attempt by hackers to telnet into the users? computer will fail because the application level firewall will recognize this telnet connection as a non-web/e-mail application and reject the information trying to enter the users? computer.
This type of firewall is known as an application-level proxy because, in addition to screening packets for the type of application they wan to run on the user?s computer, they also serve as a proxy server. A proxy can be thought of as a computer that sits between a computer and a web server and acts as a middleman between the computer and the web server.
An application-level proxy receives all communications requests from the computers behind it (or inside the firewall.) It then proxies the request; that is, it makes the requests on behalf of its constituent computers. What this does is to effectively hide the individual computers on the network behind the firewall. The targeted computers are protected from view because outside sources never make direct contact with the computers - every communication is conducted through the proxy server.
Network Address Translation (NAT)
Network Address Translation (NAT), serves as a firewall by keeping individual IP addresses hidden from the outside world. Similar to a proxy server, Network Address Translation acts as an intermediary between a group of computers and the Internet. NAT allows an organization to present itself to the Internet with one address. NAT converts the address of each computer and device on a LAN into one IP address for the Internet and vice versa. As a result, people scanning the Internet for addresses cannot identify the computers on the network or capture any details of their location, IP address, etc. And if the bad guys can?t find you, they can?t hurt you.
Drawbacks to Using Firewalls
Although firewalls have their strengths, and are an invaluable information security resource, there are some attacks that the firewalls cannot protect against, such as eavesdropping or interception of e-mail. Furthermore, whereas firewalls provide a single point of security and audit, this also becomes a single point of failure ? which is to say, firewalls are a last line of defense. This means that if an attacker is able to breach the firewall, he or she will have gained access to the system, and may have an opportunity to steal data that is stored in that system, or to create other havoc within the system. Firewalls may keep the bad guys out, but what if the bad guys are inside? In the case of dishonest or disgruntled employees, firewalls will not provide much protection. Finally, as mentioned in the discussion of packet filtering, firewalls are not foolproof - IP spoofing can be an effective means of circumvention, for example.
For optimal protection against the variety of security threats that exist, firewalls should be used in conjunction with other security measures such as anti-virus software and encryption packages. As well, a well-thought out and consistently implemented security policy is vital to attaining optimal effectiveness of any security software.
Selecting Firewalls
Firewall applications vary in sophistication and cost. For the small office or home user, the easiest and least expensive firewall solutions are personal firewalls, which are software programs that install on your computer. When selecting firewalls, the following considerations should be taken into account:
• Ease of installation/configuration
• Does the firewall run without user intervention?
• Are there parameters that have to be set, and is it easy to do?
• Is there online help or technical support available?
• Does the firewall provide audit reports identifying time, location and type of attack?
• Is the cost of the firewall appropriate to the size of your business/office?
• Are maintenance/ monitoring requirements suitable for the size and type of business?
• What will be the training requirements for the firewall?
• Will the firewall have a significant impact on the operation of the system as a whole?
There are a number of firewall products available with varying feature capabilities and costs. Most of the vendors offer a free trial for evaluation purposes and SOHO users should select one based on their needs.



What are the basic types of firewalls?
Conceptually, there are two types of firewalls:
1. Network layer
2. Application layer

They are not as different as you might think, and latest technologies are blurring the distinction to the point where it's no longer clear if either one is ``better'' or ``worse.'' As always, you need to be careful to pick the type that meets your needs.

Which is which depends on what mechanisms the firewall uses to pass traffic from one security zone to another. The International Standards Organization (ISO) Open Systems Interconnect (OSI) model for networking defines seven layers, where each layer provides services that ``higher-level'' layers depend on. In order from the bottom, these layers are physical, data link, network, transport, session, presentation, application.
The important thing to recognize is that the lower-level the forwarding mechanism, the less examination the firewall can perform. Generally speaking, lower-level firewalls are faster, but are easier to fool into doing the wrong thing.

3.2.1 Network layer firewalls
These generally make their decisions based on the source, destination addresses and ports (see Appendix C for a more detailed discussion of ports) in individual IP packets. A simple router is the ``traditional'' network layer firewall, since it is not able to make particularly sophisticated decisions about what a packet is actually talking to or where it actually came from. Modern network layer firewalls have become increasingly sophisticated, and now maintain internal information about the state of connections passing through them, the contents of some of the data streams, and so on. One thing that's an important distinction about many network layer firewalls is that they route traffic directly though them, so to use one you either need to have a validly assigned IP address block or to use a ``private internet'' address block [3]. Network layer firewalls tend to be very fast and tend to be very transparent to users.


Figure 1: Screened Host Firewall



In Figure 1, a network layer firewall called a ``screened host firewall'' is represented. In a screened host firewall, access to and from a single host is controlled by means of a router operating at a network layer. The single host is a bastion host; a highly-defended and secured strong-point that (hopefully) can resist attack.


Figure 2: Screened Subnet Firewall



Example Network layer firewall : In figure 2, a network layer firewall called a ``screened subnet firewall'' is represented. In a screened subnet firewall, access to and from a whole network is controlled by means of a router operating at a network layer. It is similar to a screened host, except that it is, effectively, a network of screened hosts.

3.2.2 Application layer firewalls
These generally are hosts running proxy servers, which permit no traffic directly between networks, and which perform elaborate logging and auditing of traffic passing through them. Since the proxy applications are software components running on the firewall, it is a good place to do lots of logging and access control. Application layer firewalls can be used as network address translators, since traffic goes in one ``side'' and out the other, after having passed through an application that effectively masks the origin of the initiating connection. Having an application in the way in some cases may impact performance and may make the firewall less transparent. Early application layer firewalls such as those built using the TIS firewall toolkit, are not particularly transparent to end users and may require some training. Modern application layer firewalls are often fully transparent. Application layer firewalls tend to provide more detailed audit reports and tend to enforce more conservative security models than network layer firewalls.


Figure 3: Dual Homed Gateway



Example Application layer firewall : In figure 3, an application layer firewall called a ``dual homed gateway'' is represented. A dual homed gateway is a highly secured host that runs proxy software. It has two network interfaces, one on each network, and blocks all traffic passing through it.
The Future of firewalls lies someplace between network layer firewalls and application layer firewalls. It is likely that network layer firewalls will become increasingly ``aware'' of the information going through them, and application layer firewalls will become increasingly ``low level'' and transparent. The end result will be a fast packet-screening system that logs and audits data as it passes through. Increasingly, firewalls (network and application layer) incorporate encryption so that they may protect traffic passing between them over the Internet. Firewalls with end-to-end encryption can be used by organizations with multiple points of Internet connectivity to use the Internet as a ``private backbone'' without worrying about their data or passwords being sniffed.


ELECTRONIC DATA INTERCHANGE
AND ELECTRONIC FUNDS TRANSFER
Electronic data interchange (EDI), or electronic data processing, is the electronic transmission of data between computers in a standard, structured format. Electronic funds transfer (EFT) is the term used for electronic data interchanges that involve the transfer of funds between financial institutions.
EDI has allowed companies to process routine business transactions, such as orders and invoices, more rapidly, accurately and efficiently than they could through conventional methods of transmission. While EDI has been around for decades, it wasn't until the late 1990s that this basic principle became a driving force in the rollout of electronic commerce, corporate extranets linking suppliers and customers, and related network-based technologies.
HISTORY
EDI has been present in the United States in some form since the mid-1960s. Businesses had been trying to resolve the difficulties intrinsic to paper-dependent commercial transactions. These difficulties include transmission speed (because of delays in entering the data onto paper and transporting the paper from sender to receiver); accuracy (because the data had to be recreated with each paper entry); and labor costs (labor-based methods of transmitting data are more expensive than computer-based methods).
In 1968 a group of railroad companies concerned with the accuracy and speed of intercompany transportation data transmissions formed an organization called the Transportation Data Coordinating Committee (TDCC) to study the problem and recommend solutions. Large companies such as General Motors and Kmart also reviewed the problems, which arose when they used their intracompany proprietary formats to send electronic data transmissions to outside parties. Because each company had its own proprietary format, there was no common standard among transmitting parties. A company doing business electronically with three other companies would need three different formats, one for each company.
By the 1970s several industries had developed common EDI programs for their companies within those industries, and a third-party network often administered these systems. Some examples of these systems include ORDERNET, which was developed for the pharmaceutical industry, and IVANS, which was developed for the property and casualty insurance industry. While these systems were standardized for each industry, they likewise could not communicate with other industries' proprietary systems. By 1973 the TDCC began developing set of standards for generic formats to handle this problem.
HOW EDI WORKS
EDI is quite different from other types of electronic communication. It is unlike a facsimile transmission (fax), which is the transfer of completely unstructured data through a digitized image. EDI also differs from other types of electronic communications among computers, such as electronic mail, network file sharing, or downloading information through a modem. In order to access electronic mail messages, shared network files, or downloaded information, the format of the computer applications of both the sender and the receiver must agree.
Since EDI uses a defined set of standards for transmitting business information, these standards allow data to be interpreted correctly, independent of the platforms used on the computers that transmit the data. When a sender transmits data, such as a purchase order, the EDI translation software converts the proprietary format of the sender's document processing software into a mutually recognized standard format. When the receiver obtains the data, the EDI translation software automatically converts the standard format into the receiver's proprietary document processing format. Because of the speed and accuracy of an EDI, users find that the system saves time and reduces costs over paper-based business transactions.
MODERN EDI
By the 2005, major retailers relied heavily on EDI to exchange purchase orders, invoices, and other information with their trading partners. In a June 2004 poll of 20 retailers, the majority said that they were either adding new trading partners or increasing the number of EDI transactions. It is estimated that between 80 and 90 percent of business-to-business traffic is conducted through EDI, and this number is growing 3 to 5 percent annually. Retail giants such as Wal-Mart Stores Inc., J.C. Penney Co., Supervalu Inc., and Hallmark Cards Inc. have been regular users of EDI. In fact, Wal-Mart has been one of the most influential companies driving new technology trends.
Since 2003, many companies have turned to a new technology in which data is transmitted over the Internet using the Applicability Statement 2 (AS2) protocol. The AS2 rules describe how to send data securely and ensure that the messages are received.
In September 2002, Wal-Mart asked its suppliers to switch from value-added networks (VANs) to AS2. Other companies have followed suit. One company claimed to have cut its costs by 70 percent after switching from a VAN to AS2. However, others have decided not to make the switch because of the costs involved.
Retailers are not the only businesses to take advantage of this technology. The healthcare industry also uses EDI to exchange patient information between medical providers and insurance companies. EDI is such a reliable means of transmitting data that a growing number of third-party payers, including Medicare, Medicaid, and commercial insurers, have started to require providers to submit claims electronically.
The Electronic Data Interchange rule was developed as part of the Health Insurance Portability and Accountability Act (HIPAA) and required compliance by October 16, 2003. This law requires all entities that transmit clinical data (including claims, referrals, and eligibility verification) to use the same electronic data file format. This can be accomplished by purchasing and maintaining a HIPAA-compliant practice management system (PMS) or by transmitting the data through a clearinghouse. The PMS is not the most cost-effective option for smaller entities, as it usually requires an administrator to maintain and upgrade the system as necessary. With the clearinghouse option, the entity sends data to a clearinghouse. The clearing-house then sends the data to the appropriate recipients in the appropriate format.
ELECTRONIC FUNDS TRANSFER
An electronic funds transfer (EFT) is an EDI among financial institutions in which money is transferred from one account to another. Some examples of EFTs include electronic wire transfers; automatic teller machine (ATM) transactions; direct deposit of payroll; business-to-business payments; and federal, state, and local tax payments.
In general, EFT transactions are transferred through an automated clearing house (ACH) operator. An ACH operator is a central clearing facility operated by a private organization or a Federal Reserve bank on behalf of participating financial institutions, to or from which financial institutions transmit or receive ACH transactions. The ACH network is a nationwide system for interbank transfers of electronic funds. It serves a network of regional Federal Reserve banks processing the distribution and settlement of electronic credits and debits among financial institutions.
ACH transactions are stored in an ACH file, which is a simple ASCII-format file that adheres to ACH specifications. A single ACH file holds multiple electronic transactions, each of which carries either a credit or debit value. Typically, a payroll ACH file contains many credit transactions to employees' checking or savings accounts, as well as a balancing debit transaction to the employer's payroll account. An originating bank sends electronic payment instructions to a receiving bank. In those instances, the electronic transfers are processed in batches and settled within a few days.
The National Automated Clearing House Association (NACHA) oversees the ACH network and is primarily responsible for establishing and maintaining its operating rules. All financial institutions moving electronic funds through the ACH system are bound by the NACHA Operating Rules, which cover everything from participant relationships and responsibilities to implementation, compliance, and liabilities. While the NACHA rules are specific and quite detailed, adhering to a strict set of rules is crucial to the smooth and successful operation of the ACH system.
As the use of home computers becomes more and more a part of everyday life, the popularity of online banking and online bill payments continues to grow. Many banks allow their customers to access account information over the Internet and to transfer funds between accounts. Many credit card companies and utility companies allow customers to pay their bills online through EFTs. Online bill payments can save the consumer time and money. The customer can pay a bill in a matter of minutes over the Internet instead of spending money on postage to send a paper check and risking the chance that the bill may arrive past the due date.
On October 28, 2004, the Check Clearing for the 21st Century Act, also known as Check 21, took effect. This federal law allows banks to transmit checks electronically and substitute electronic images for original paper checks. Check 21 provides many advantages for banks and financial institutions. By transmitting checks electronically, banks can reduce the amount of time it takes to receive funds. This is because they no longer have to wait for another bank to receive paper checks before they send the funds. In addition to saving time, Check 21 saves banks millions of dollars in transportation and storage costs.
While Check 21 has made the banks happy, it has made many consumers unhappy. Many people write checks thinking that it will take at least two or three days for them to clear, thus giving them time to deposit the appropriate funds to cover the check. However, with Check 21 banks can clear checks within 24 hours of receiving them, cutting this safety net by days in many cases. In addition, although banks can process checks and debit the customer's accounts right away, they can still hold out-of-state checks for five days or more.
Consumer groups complain that this law increases the chances of fraud, error, bounced check fees, and inconvenience. There may be times when a bank cannot accept an electronic check image. In that case, the other bank could create a substitute check that has the same legal weight as the paper check. Having both the original check and a substitute check around could result in both checks being cashed, either fraudulently or by an honest mistake.



Types of ecommerce

Ecommerce (e-commerce) or electronic commerce, a subset of ebusiness, is the purchasing, selling, and exchanging of goods and services over computer networks (such as the Internet) through which transactions or terms of sale are performed electronically. Contrary to popular belief, ecommerce is not just on the Web. In fact, ecommerce was alive and well in business to business transactions before the Web back in the 70s via EDI (Electronic Data Interchange) through VANs (Value-Added Networks). Ecommerce can be broken into four main categories: B2B, B2C, C2B, and C2C.

B2B (Business-to-Business)
Companies doing business with each other such as manufacturers selling to distributors and wholesalers selling to retailers. Pricing is based on quantity of order and is often negotiable. Business to Business e-commerce has been in use for quite a few years and is more commonly known as EDI (electronic data interchange). In the past EDI was conducted on a direct link of some form between the two businesses where as today the most popular connection is the internet. The two businesses pass information electronically to each other. B2B e-commerce currently makes up about 94% of all e-commerce transactions.


B2C (Business-to-Consumer)
Businesses selling to the general public typically through catalogs utilizing shopping cart software. By dollar volume, B2B takes the prize, however B2C is really what the average Joe has in mind with regards to ecommerce as a whole.

B2C, sometimes also called Business-to-Customer, describes activities of E-businesses serving end consumers with products and/or services. B2C relationships are often established and cultivated through some form of Internet marketing.

Advantages of B2C e-commerce
• Shopping can be faster and more convenient.
• Offerings and prices can change instantaneously.
• Call centers can be integrated with the website.
• Broadband telecommunications will enhance the buying experience.


C2B (Consumer-to-Business)
A consumer posts his project with a set budget online and within hours companies review the consumer's requirements and bid on the project. The consumer reviews the bids and selects the company that will complete the project.

Consumer to Business is a growing arena where the consumer requests a specific service from the business.

Example: Harry is planning a holiday in Darwin. He requires a flight in the first week of December and is only willing to pay $250. Harry places a submission with in a web based C2B facility. Dodgy Brothers Airways accesses the facility and sees Harry's submission. Due to it being a slow period, the airline offers Harry a return fare for $250.


C2C (Consumer-to-Consumer)
There are many sites offering free classifieds, auctions, and forums where individuals can buy and sell thanks to online payment systems like PayPal where people can send and receive money online with ease. eBay's auction service is a great example of where person-to-person transactions take place everyday since 1995.

These sites are usually some form of an auction site. The consumer lists items for sale with a commercial auction site. Other consumers access the site and place bids on the items. The site then provides a connection between the seller and buyer to complete the transaction. The site provider usually charges a transaction cost. In reality this site should be call C2B2C.


Companies using internal networks to offer their employees products and services online--not necessarily online on the Web--are engaging in B2E (Business-to-Employee) ecommerce.


G2G (Government-to-Government), G2E (Government-to-Employee), G2B (Government-to-Business), B2G (Business-to-Government), G2C (Government-to-Citizen), C2G (Citizen-to-Government) are other forms of ecommerce that involve transactions with the government--from procurement to filing taxes to business registrations to renewing licenses. There are other categories of ecommerce out there, but they tend to be superfluous.


Another 24 hours (check out the video)

Its been a gloomy day to start with. I expected a bright sunshine to hit over me in the morning,but it was all cloudy and that really did hamper my rising up.A bit too late to get up and sluggish to start with the things, but soon I picked up the pace and this time dashed to the television,switched it on and jumped into a News channel to look out for the results of Champions league final, it was a sad news,Chelsea lose in the penalty shoot out.I think yesterday was not a good day for me in sporty terms. But again I had a serious hope that they would thrash off ManU a revenge for their lose of English premier league title,but now I can only have that revenge in dreams. I was a bit disturbed to see that the fans of both teams clashed at various places, I wonder how it served the purpose of the game.I still dont understand people still show worthless emotional melodrama that doesnt even benefit them.

After the breakfast, I took my books on management and started reading,this time I made sure that I would do serious reading and so didnt get much into surfing even though I was online throughout. But again soon I fell asleep and it was around 1pm that I woke up and knew I wasnt actually reading. I was agitated, but none to be blamed other than me. It was time for lunch and this time,against the conventions that I follow, I thought of studying instead of sleeping.I went through the strategic and tactical management acrobatics , I never liked this subject, but I happen to be choiceless. Once it was evening, I just lied in the bed for half an hour,got up had a bath and then my tea.Thats when I listened to the news and heard about the recent raids in houses of various "Godmans" in my state.I wonder how long this commitment in the issue would be carried out by authorities.Then there was a news where a naval officer and his lover killed a person from film industry,sliced him into 300 pieces and burnt the pieces down.I think may be they are the best butchers you would see around at present.I wonder about their emotional balance while they were doing this clinical act,might be an inspiration from the movie "Equilibrium" where people very well stay emotionless.

Now its almost 7pm and I am writing this note now cause I dont feel there is much more incidents to strike my way today.There is a cricket match left for the night that I would be tracking through net, then the usual stuff of surfing and reading a bit.AH!! I forgot to tell you ,today I heard a very brand new song,infact a video of a song from the album" coffee at mg road".Its a funny hiphop song but I am sure you will enjoy ,it check it out.Meanwhile let me take leave.Another eventless day passing by,but this time no complaints,no issues. Hope you had a nice day and wish you a brighter day ahead.

-Varun Krishna


May 21, 2008

My day

Its been so long now that I have been thinking of transforming my blog more into a diary where I can put on my each moment of life and share with you,may be I feel this thing being one of my best friends.So I start off, my mission to put each and every instance of my every single day onto my blog.

I dont think I need to put in that I get up at some time brush my teeth and bla bla,I think I should put in more of the novelty that I bring into or possibly I face in my day.So starting off ,got up as usual around 6 am, straight away moved into the system switched on and started my mission of downloading the movies and songs and ofcourse not to forget Linkreferral stuff.Morning was much eventless,the usual south Indian breakfast,a bit brushing through newspaper starting with last page( which ofcourse is the sports page). Then back to my room,took my books as my final sem exams are right near the door.And you would guess that I started reading.I wanted to ,so I logged in back to internet and to the world of my blog, orkut and chatting with my friends.Probably this happens to be the way I study.I dont think I am addicted to internet,but moreover it happens to be something that I breathe every moment,so I am happy to study along with surfing as long as it doesnt end up in a disaster.

It was noon and after having lunch I was back to bed after a "busy working session" in the morning.Around 4pm, I got up and got to the ground near my home where some of us hang around for playing cricket.Its more a get together that we aim in the evenings and this has been a real wonderful time.

I have been a true believer of God, I dont mean to say I am religious or I believe in idols,but I have always believed that there is a super power that controls us,that always save us in troubles even though we might be tested a bit before he finally stretch out his hands.Probably today I got a solution to one of the issues,infact a dilemma that has been howering around me for months now,something for which I never had an answer and whenever I tried to find one,I always ended up putting myself in more of a trap.Now finally he has shown me the way and I am happy with the solution God has given me even though it hurts a bit.But i feel it is better to be hurt now rather than having a hell out later.And finally in the evening it was time for the IPL cricket match. I was happy to see my team perform well,my star and the little master playing a classic innings but all ending in vain with my team losing just by 1 run.

I really cant understand the human thought,infact I dont know if its only me who feels this.Everything in the day went alright except the match result,but I felt so depressed at the end of the match that I happened to be speechless. I felt my whole day went wrong because my team lost the match.I think its high time for me to realise that all neednt be terrible that do not end well. Some days defeat happen to be the order of the day and our victory is to take the positives out of it and move on.But many a time my words never get into action.I hope my team performs well in the next match,they went down fighting and thats the spirit that I take in my life,not that I would wait for a failure and then get into thick of things,but act when am required to.Now am feeling a lot better.Once again, my blogging has helped me to recover out of a quite untimely and wasteful depression.Its about taking things the way it deserves,but the lessons from each moment needs to pump you in for a brighter tomorrow.I look forward for a better tomorrow even though today was never worse.Hope and aspiration being the key and the rest follows.Hope even you had a brighter day.


-Varun Krishna

May 19, 2008

Its too much done

This is the continuation of the post I put just before this.I was talking about the happiness that we were feeling once we knew that our exams are postponed.But now I feel ,for me ,that elation has transformed into the agony once I got the timetable.The exams that were to be over by this month has been stretched off to the end of next month.So that clearly means we would not be finishing our course in time, may be it gets to extend by a month or two.

Now who is to blamed,we have a custom of putting each and every blame on our dear university,may be in the past it might be right or wrong,but this time I would not certainly take that step.But even we students arent to be blamed,we had genuine reason to postpone the exams and we have every right to justify our step.May be its fate or destiny thats pulling our engineering life long.We dont mind that ,but we would certainly be worried about the uncertainty that hangs over our career.Its too late for us to rectify or to be rectified.But whatever is in store we have to face it and we are gearing up for the kill.

Its done

You must not be expecting me to write a post over here when I am supposed to be preparing for my final semester exam starting from tomorrow,but it has been postponed to next week.I dont know if this is gonna be causing trouble to me (as my course would be extended further) in the coming future or not,but as far as I am concerned,now its festive mood out here.I would like to thank all those people who have worked hard to get this done.In a way we have got more time to prepare,but the question being would we be serious enough and start studying now.But those are latter issues and what matters now is how to rockkkkk this moment.I heard my dear friends are celebrating this moment and let me move now to be a part of it.Have a nice time guys.

May 6, 2008

Defining religion

(This is an article I published in Associated content 8 months back and I thought I would share it with you)
It is said God created men ,he created religion and he recreated Gods ,seems strange but when we closely analyze the present scenario this seems to be the fact.The preachers of all religions have defined religion as a way of thought,action and vision that would finally take one to eternal truth and wisdom called God.But do you think is that what we see in the present world? Were the religions made for acting as a catalyst to communal tensions and emotional vibrancy over regional spirit? well I really doubt it.

Here let us try to redefine the word RELIGION and find a true meaning to it.Religion can never be defined by, but is experienced and felt by.It is a way of life which leads a human being to live a peaceful and moreover a meaningful life.All religions might have different customaries ,different ways of worship and infact different ideologies, but these are all like different rivers that fall into the ocean finally where there is no water of specific river ,its all one;similarly all religions through different channels finally take you to the single god ,some call it God, some call it Bhagwan whereas some call it Allah.Its the same God that we all worship,its the same truth that we all finally arrive at .But still......

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