Speed up web browsing with OpenDNS

When you type in a domain name such as ipgoat.com in your browser the computer must resolve the friendly name into an IP address of the server to download the web page and supporting files. Windows uses a DNS (domain name system) server to lookup this information. By default, Windows uses your ISP’s DNS server. Depending on your provider, the performance of their DNS resolving server varies. Some large national providers are known to provide unreliable and slow DNS servers.

The performance of the DNS server you are using is one component that affects the speed of your internet browsing. Since each domain name you type in must be resolved into an IP address, the amount of time that takes will delay the loading of any web page. Some users with overloaded ISP DNS servers can see delays in multiple seconds before web pages start to load.

OpenDNS provides free alternative DNS servers that anyone can use with any internet provider. Unlike many national internet providers, OpenDNS’s DNS servers are very fast and reliable. Using OpenDNS servers instead of your ISP servers will help you speed up your internet browsing by cutting down on the delay between resolving a domain name and getting the IP address so your browser can start loading the web page.

Configuring your computer to use OpenDNS servers instead of your ISP’s is a simple change that works in both Windows XP and Windows Vista:

1. Click on the Start Button and type in ncpa.cpl and hit Enter. In Windows XP Click on the Start Button, click Run and then type in ncpa.cpl
2. Right click on your active network connection that you use to connect to the Internet and select Properties.
3. On the Networking / General tab, select Internet Protocol (TCP/IP) (version 4 on Windows Vista) and hit Properties.
4. On the properties screen, select Use the following DNS server addresses and then type in 208.67.222.222 in the preferred and 208.67.220.220 in the alternate boxes.

A recent survey has shown that only 22% of broadband providers actually advertise the true limits of the usage of their package. Despite claims of ‘unlimited’ bandwidth and downloads, customers are still finding their usage capped. Figures released also showed that 56% of those advertising unlimited packages actually capped customer’s usage, even cutting some off if they used it to the excess.

For many households broadband has become a necessity. Just as we need Electricity, Gas & Water, many users rely upon the internet to go about their every day life. Products like this need to be more transparent in order to give the customer a much clearer view of what they’re purchasing and the limits that will be in place.

However broadband providers could argue that people exceeding the usage is minimal, as limits are often set at 40 times the average download usage per customer. In fact research conducted by Internet Service provider TalkTalk, showed less than half its customers used less than 1GB which is only the equivalent of downloading 2 films a month. Also research has shown only 1 in 4 read the terms and conditions outline the allowed usage.

With the growth of sites like 4ondemand and the BBC and ITV iplayers, download demand is expected to increase significantly. With the increase in demand, providers are likely to offer an extended service but like everything, it will come at an added cost. Some, like Virgin already offer the service although when traffic is heavy the usage is shaped and will be significantly slower at busier times of day.

Switches and routers are special devices that enable you to make connections between and among computers, printers, peripherals, networked devices and/or other networks. A switch or a router has at least two ports into which you plug devices’ cables to make the connection, but the similarities more or less end right there. What goes on inside these units is what distinguishes one from another. The terms are often used interchangeably, which is dead wrong, and using the devices incorrectly can result in a network that is just plain dead.

Switches do what simpler devices called “hubs” do, but much more effectively, which is why hubs are decreasing in popularity. A switch will essentially “learn” about the network “traffic” that flows into and through it, and remember what the particular “addresses” represent. For a basic example, a switch will sense traffic from Computer #1 arriving via Port #2, so it knows that any signals that are bound for Computer #1 will have to go out that particular port, as well. Whereas the older, simpler hubs send every signal everywhere, a switch only sends traffic exactly where it needs to go. Busy networks will run dramatically faster with proper switches installed.

Routers big and small

Routers are many orders of magnitude more complex than simple, straightforward switches, and there are many different models in many different form factors from which to choose. Routers can be anything from a small, paperback-book-size, four-port, wireless broadband router to the mammoth and powerful devices that are the traffic cops at the main intersections of the Internet itself. Without these “intelligent appliances,” there would be no World Wide Web as there is today.

Simply put, a router is specialized computer that is programmed for its various important functions. It needs to be aware of the network data, as well as manage and manipulate it in various ways when required, while it also works tirelessly to route data both quickly and correctly. Today’s broadband routers use their special firmware (built-in software) to camouflage or hide computers behind what’s called a firewall. All routers have the ability to configure the handling of the network traffic through some kind of user interface running on the “administrator’s” computer.

Speed and connectivity

You will see a few terms that apply to both of these devices, the most important of which is network speed. Today’s switches and routers are commonly capable of both current and “legacy” (a fancy word for “old”) speeds, and will often be labeled 10/100/1000. These figures refer to the number of megabits, or millions of bits, per second (mbps) the device can handle. You may have or see some older devices labeled with only one speed, which limits its use to devices operating at the same level. However, “gigabit” devices (1000mbps) are the most common now, and as 10/100/1000 devices they handle all speeds well.

A growing number of home and business networks have gone wireless, and the trend is accelerating all the time. The technical term for the wireless router protocols are 802.11b, 802.11g and the newest one, 802.11n. Wireless transceivers in these routers basically add more “virtual ports” to the device. Wireless or wired, routers are standard equipment these days, and falling prices combined with increasing technological sophistication will see to it that they continue to spread.

There are some people who think that switches will eventually disappear as far as home use is concerned, although large businesses and web server companies will need them for a long time to come because of the varied connectivity requirements of their operations. As the so-called digital convergence continues, routers may end up being combined with cable or DSL modems to eliminate multiple pieces of equipment in the standard home or small-business network. If past is prologue in this field, then we can expect both switches and routers to get smaller, better, faster and cheaper all the time.

Why Computers and Networks?

Computers have become a necessity for all types of working environment. No matter what type of work you are doing, computers can help you in maximizing your work efficiency. Due to this fact computers are being used in all types of offices. Some areas like banking, insurance, stock exchange as well as reservation systems completely rely on use of Computers and Internet.

In a computing environment people need inter connectivity of computers to share resources like (files and data). It further helps in use and management of information collected through various nodes. These kinds of network that is being implemented in a particular organization are known as Intranets. Intranet helps in information sharing between different offices of same organization at different locations. It works on LAN (Local Area Network), MAN (Metropolitan Area Network) or WAN (Wide Area Network). There are mainly three ways of implementing different type of networks – wired, wireless or mixed (wired and wireless both as and when required).

Why Internet?

Internet is information superhighway, one of the major and accurate sources of getting information on any topic quickly. It is also used as backbone for implementing Intranet. Company’s websites and email are completely dependent on Internet. In brief, internet is the most important and fastest medium of communication in current hi-tech world.

Network Related Problems

As an end user you must have experienced various types of problems in your network during your work. Due to network downtime organizations have to bear loss of several productive working hours or in turn loss of revenue. Network downtime for your web servers may result unavailability of your website, in that case your potential viewers may not find required information through your website. It may create a negative impact of your company/organization or business

To deal with such problems immediately organizations need network diagnosis and maintenance experts to fix such problems to further reduce loss of productive working hours. However, it is not possible for every organization to hire a fulltime team of networking experts to solve their network issues. They prefer to rely upon network security consultants, who help them whenever needed. It’s a cost-effective alternative for organizations because they don’t have to hire full time professionals for taking care of their network troubleshooting needs.

In your car, the firewall sits between the engine compartment and the front seat and is built to keep you from being burned by the heat of the combustion process. Your computer has a firewall, too, for much the same reason – to keep you and your data from being burned by hackers and thieves who are the unfortunate creators of “Internet combustion” and destruction.

The firewall, a “combo” approach of software that regulates and monitors hardware and communications protocols, is there to inspect network traffic and all the “packets” of information that pass through to your inner sanctum, your CPU and hard drives. A firewall will rule out the possibility of harm, or at least greatly minimize, by noting and quarantining potentially harmful “zones” and will either deny or permit access to your computer based on the current set of rules that applies at the time, depending on many (very many) factors.

Basic tasks and settings

The basic task for a firewall is to regulate of the flow of traffic between different computer networks that have different “trust levels.” The Internet is full of countless overlapping zones, some safe and some totally deadly. On the other hand, internal networks are more likely to contain a zone or zones that offer a bit more trust. Zones that are in between the two, or are hard to categorize, are sometimes referred to as “perimeter networks” or, in a bit of geek humor, Demilitarized Zones (DMZ).

Without proper configuration, a firewall can simply become another worthless tool. Standard security practices call for a “default-deny” firewall rule, meaning that the only network connections that are allowed are the ones that have been explicitly okayed, after due investigation. Unfortunately, such a setup requires detailed understanding of network applications and a great deal of time and energy to establish and administer.

Who can do what?

Many businesses and individuals lack sufficient computer and network knowledge to set up a default-deny firewall, and will therefore use a riskier but simpler “default-allow” rule, in which all traffic is permitted unless it has been specifically blocked for one of a number of possible reasons. This way of setting up a firewall makes “mysterious” and unplanned network connections possible, and the chance your system may be compromised becomes much more likely.

Firewall technology had its first growth period in the computer technology revolution of the late 1980s, when the Internet was a fairly new in terms of its global reach and connectivity options.

The predecessors to today’s hardware/software hybrid firewalls were the routers used in the mid 1980s to physically separate networks from each other. However small the Internet began, it was ultimately undone by supremely fast growth and the lack of security planning, and therefore there were the inevitable breaches caused by older (”prehistoric”) firewall formats. Fortunately, computer pros learn from their errors, and the firewall technology continues improving daily.

DSL (Digital Subscriber Line) is a technology that enables to use the unused bandwidth that already exists on a regular phone line to deliver fast digital data transmission without affecting the analog telephone service used. DSL, which also commonly known as xDSL or ADSL, uses ordinary copper telephone wiring to deliver a high-speed, downstream (from the Internet to your computer) channel to subscribers and a lower-speed, upstream (from your computer to the Internet) channel to the network while at the same time providing POTS ( Plain Old Telephone Services).

DSL technology has added a new twist to the utility of telephone lines. Telephone lines, which were constructed to carry a single voice signal with a 3.4 kHz bandwidth channel, can now convey nearly 100 digitally compressed voice signals, or a video signal with quality similar to broadcast television.

DSL technologies increase the information-carrying ability of traditional copper wires. DSL enables high-speed multimedia services such as video-on-demand, Internet access, distance learning, remote corporate LAN access, and videoconferencing for anyone with access to a clean copper line.

ADSL is able to convert the existing information system network from one limited to voice, text, and low resolution graphics to a powerful network that can deliver multimedia to everyone’s home or small business. Implementation of ADSL is quick at up to 1.5 Mbits/s and 512 kbits/s upstream. That’s about 30 times faster than today’s analog modems.

How does DSL work?

DSL allows for greater bandwidth by utilizing more of the bandwidth available on a common analog line and connecting digitally on both the uplink and downlink connection.

DSL modems can provide downlink connection speeds greater than 6 Mbps and uplink speeds of 640 Kbps, or as much as 1.1 Mbps in both directions.This makes DSL not only much faster than 56K analog modems, but also faster than ISDN and rivaling cable modems in bandwidth. This allows phone companies to compete with cable Internet Service Providers. Because many of the expected applications for DSL involves digital, compressed video, forward error correction is employed to reduce impulse noise error with symbol-by-symbol error correction to counteract continuous noise.

DSL is not a bus-related technology like analog or cable modems. With DSL, bandwidth rates available are more consistent to the end user. There is a geographic requirement that the end user must be within 18,000 feet of the central office or signal degradation will become too great and DSL unfeasible.

Today, the majority of application protocols use the Internet’s reliable Transmission Control Protocol (TCP). The functionality of TCP is designed to be adequate not only for Internet applications but also for the variety of underlying networks.

The protocol aims at providing a reliable service with the following features:

1. Fairness to other flows that potentially share a channel’s bandwidth

2. Dynamic discovery of current availability of bandwidth

* 1. Mechanisms for congestion avoidance and control and for optimization of the error recovery process.

Error control mechanisms are the central component of reliable protocols. They affect a protocol’s performance with respect to goodput, energy expenditure, and overhead. Error control is usually a two-step process: error detection, followed by error recovery . TCP assumes a relatively reliable underlying network where most packet losses are due to congestion . TCP error control is centered on congestion losses and ignores the possibility of transient random errors or temporary blackouts due to handoffs and extended burst errors that are typical in wireless networks. TCP detects errors by monitoring the sequence of data segments acknowledged (received). When timeouts are correctly configured, a missing segment is taken to indicate an error, namely that the segment is lost due to congestion (i.e. buffer overflow). Reliable protocols usually implement an error recovery strategy based on two techniques: retransmission of lost segments; and downward adjustment of the sender’s window size and readjustment of the timeout period. When using TCP over wireless links results in congestion control measure being invoked at the source.

The Additive Increase Multiplicative Decrease (AIMD) algorithm is used to implement TCP window adjustments; based on the analysis the algorithm achieves stability and converges to fairness in situations where the demand (of competing flows) exceeds the channel’s bandwidth .

In a wireless network, however packet looses will occur more often due to unreliable wireless links than due to congestion. It is shown that the performance of TCP is sensitive to the packet size, and that significant performance improvements are obtained if a ‘good’ packet size is used. Packets on the internet may get lost either due to congestion, or due to corruption by the underlying physical medium. Given the low error rates of wired links, almost all losses are related to congestion. TCP’s reaction to looses is based on this very observation. Losses are detected either by timeouts at the source or by multiple duplicate acknowledgements ( dupacks ) from the receiver. TCP assumes that each packet loss is solely due to congestion. However, in a wireless network, TCP will encounter packet looses that may be unrelated to congestion. Nonetheless, these losses trigger congestion control measures at the source and severely degrade performance.

TCP was designed and carefully calibrated to overcome the problems like as follows:

* 1. Stability.
* 2. Heterogeneous ( receiver buffers, network bandwidth and delay ).
* 3. Fairness in bandwidth consumption of competing flows.
* 4. Efficiency in utilization.
* 5. Congestion control ( that effectively avoids situations of congestive collapse ).

Transmission Control Protocol (TCP) is a means for building a reliable communications stream on top of the unreliable packet Internet Protocol (IP). TCP is the protocol that supports nearly all Internet applications. The combination of TCP and IP is referred to as TCP/IP and many people imagine, incorrectly, that TCP/IP is a single protocol.

Performance Metrics of TCP :

Goodput :

This is the measure of how efficiently a connection utilizes the network. It is determined as the ratio of useful data received at the destination and the total amount of data transmitted by the source. If a connection requires a lot of extra packets to traverse the network due to retransmission, its goodput is low. It is desirable that each connection have as high a goodput as possible. Clearly, this metric is of great significance for efficient operation of a network.

Throughput :

This is the measure of how soon an end user is able to receive data. It is determined as the ratio of the total data received by the end user and the connection time. A higher throughput will directly impact the user’s perception of the quality of service.

In the niche of online marketing, ecommerce is growing at a rapid speed. It is well established in the amount of selling and buying of products and services via internet and several other computer networks.

E-commerce web site hosting is the crucial aspect if you are striving to join in the ecommerce bandwagon. Coupled with ecommerce web hosting service are other features needed for a successful web presence in the sphere of ecommerce.

Those who are pretty accustomed with the off-line selling of products and services will be able to sell the products online at ease. The quantity of products to be sold on a day-to-day basis depends on the e-commerce hosting package selected by you.

Ecommerce provides a secure connection so that you can receive and send the important data. The important data are account numbers, PIN numbers, passwords via Internet which can be send without the risk of any kind of disclosure. The secure connection means the website address must have an https before the website address. If the website is not a secure one the potential customers will not reveal the authentic information like credit card or bank account numbers since they are aware that it is not safe.

You can free yourself from all the worries of security of the website with a Secure Sockets Layer certificate. Once you meet up all the requirements for the Secure Sockets Layer Certificate you will just have to pay an installation fee to get started.

Are you looking for a hassle free financial transactions? A third party gateway can be your solution. PayPal is a major third party gateway. You will just have to pay a small amount from each of the sale made by your company.

While selecting for the e-commerce web hosting solution just check the attribute of shopping carts. Shopping carts are the web hosting ecommerce software that are installed in the hosting account that will help the customers to navigate your website pretty conveniently. It will also provide a structure to your site.

The shopping carts arrange the products in different categories. It guides the customers to track the product they are looking for. The shopping carts also keep a record of the customers and the products bought by them.

Another objective of e-commerce web hosting is the quick loading of web page. The speedy accessibility of webpage depends upon the size of bandwidth. The bandwidth is again dependent upon the data that is transferred across the internet connection.

Ecommerce hosting solutions with round the clock effective technical support and reliable web hosting can automate your business within no time.

The world of computers and information technology is going through an era of an electronic terrorism, in the form of the computer virus. It is a problem that is potentially so dangerous that it threatens the proper functioning of the virus system in today’s information age.

The virus whether biological or electronic is an information disorder. Biological viruses are tiny genetic codes DNA or RNA that take over the machinery of a living cell and are capable of marking thousand of replicas of the original virus. Like its biological counterpart, a computer virus carries in it an instructional code that makes copies of itself.

Computer viruses are computer programs which are a collection of coded instructions. The basic difference between a normal program and virus is that viruses are self replicating; they have the capacity of executing themselves without being asked for. The ‘Computer virus’ is a very broad term in itself and includes not only viruses, but also worms and Trojans.

Classification of Computer viruses:

Viruses are classified on the basic of their mode of existence and there are three categories of viruses.

1. BOOT Infector
2. SYSTEM Infector
3. GENERAL EXECUTABLE PROGRAM Infectors

BOOT Infectors:

As the name suggests, they are characterized by the fact that they are physically reside in the boot sector [0] sector of the disk. A system infected by such a virus will have the virus residing in a particular area of the disk rather then in a program file. These viruses get loaded soon after the Power Of Self Test and control the system and remains in control at all times. They some times have the capacity to trap soft booting (CTRL ALT DEL) and remain in control even if the system is booted from a non infected floppy, thereby contaminating the clean floppy.

SYSTEM Infectors:

The second category of virus deals with components of the system itself. All machines without execution require an operating system in order to create an environment in which the operator works. In MS-DOS, COMMAND.COM contains all the internal commands. If no such command file exists, commands such as COPY, DIR etc. are not loaded into the memory when the machine is booted. The system infectors attach themselves to a file such as COMMAND.COM or other memory resident files and manipulate these files.

GENERAL EXECUTABLE PROGRAM Infectors:

From the infection point of view, these are most dangerous and devastating of the three classes of viruses. They attach themselves to program files and can spread to almost any executable program in any system. These viruses change the original program instructions into a “jump” to its own code and follow that code with a return to the original program. As a result, whenever the program is executed, the virus gets loaded and executed first and then allows the original program to process. It remains memory resident and infects each and every program that is loaded for execution.

Types of Viruses:

Worms:
A worm is software that uses computer networks and security holes to replicate, or affect other programs. A copy of the worm passes through the network to another machine that has a specific security hole. It then copies itself to the new machine, and then starts replicating from there.

Macros:
Macro viruses’ use commands-called macros-embedded in the other software applications to infect and spread to other files used by that software. For example, Microsoft Word and Excel have macros, and macro viruses can spread by exploiting these commands.

Boot Sector viruses:
Boot sector viruses are older types of virus and are not so common today. They used to infect computers startup programs, so that the virus would become active as soon as the computer started up.

Trojan Horses:
Trojan Horses are programs that claim to perform a particular function but which in fact do something different. For example, they could infect your computer with a virus or erase your files.

Backdoor Trojans:
Backdoor Trojans are programs that allow other computer users to remotely control your computer via a local area network or the internet.

Resident Viruses:
These types of virus hides permanently in the RAM memory. From here it can control and intercept all of the operations carried out by the system corrupting files and programs that are opened, closed, copied etc.

Direct Action Viruses:
When a specific condition is met (such as the execution of the virus) these virus will go into action and infect files in the directory or folder that it in and others as well.

Overwrite Viruses:
These types of viruses are characterized by the fact that it deletes the information contained in the files that it infects, rendering them particularly or totally useless once they have been infected.

How do I make a Mobile Device Website?

Mobile Devices like the BlackBerry and Pocket PC are becoming ever more popular. People are moving away from the office so that they can become more productive.

As this trend continues it becomes even more popular for the webmaster or business to have a website that is friendly to a mobile device.

It’s best to retain those web users and maybe even gain a few new one in the process. Website’s specifically engineered for mobile devices do just that.
Why can’t mobile devices use the same website as pc’s and mac’s?

Well the main reason is that the pages are way to large. Most websites are made to be viewed at a 1024×768 resolution or at least 800×600. Well the BlackBerry 8730e has a resolution of 320×240. It’s the equivalent of looking at a map through a pinhole.

So what needs to be done? We need to lower the resolution of the web page. Because we can’t expect 90% of your users that are on PC’s to look at a tiny website on their screen we need to create a duplicate site.

There are a few solutions, but the best one in my opinion is to do it by hand. 1st consider why someone would be viewing your website from a mobile device? There are a few main reasons:

1. Looking for email address
2. Looking for phone number
3. Looking for location
4. They want to know more about your company

OK. I’m getting ahead of myself here. So we must create a second website for mobile users. Most people choose to go with the mobile.yourwebsite.com approach. I think that creating a subdomain is probably the best and fastest way to deal with the situation.
Creating Subdomain for Mobile on Apache Web Server

If you are running your site on an apache web server chances are that it has cpanel and in cpanel there is a create subdomain icon/text. If this is the case go there and follow those directions. It will then create a folder on your site like so. http://www.yoursite.com/mobile/ and when users go to mobile.yoursite.com it will show the contents of the mobile folder.

Creating Subdomain for Mobile on IIS Server

Creating Subdomains on an IIS Server is a little more tricky than on Apache. First, you must create a folder in the inetpub called mobile. Then you need to add the new website by right clicking My Computer going to Manage and then Services and Then IIS then Web Sites. Create a new website naming it Mobile Site, then make sure that the properly / Home Directory Tab is showing the contents of the mobile folder. Then go to the control panel and select network devices and right click your network connection and go to properties. Then click the advanced button and make sure the tab is on IP Settings. Add an IP address (a new one not the same one as your other site) and then save all that.

Now you need to NAT the incoming request for mail.yoursite.com to that internal ip address. I may have skipped a step or two - but I think I have all that covered. If you have questions, just google “Subdomain Setup IIS Tutorial”

Now back to what we where talking about earlier, making a few pages specifically for the mobile device browsers…

You need to create at least 4 different pages:

• Email Directory
• Phone Directory
• Location
• About

If your organization is not that large you can probably compress Email / Phone directory into 1 contact page.

These pages need to be minimal. Minimal text, minimal tables, minimal pictures ect. Also NO FRAMES, NO JAVASCRIPT, and NO FLASH as most mobile device browsers can’t read any of those.

Assuming that everything goes well, you should have a mobile friendly website that can be viewed by any user anywhere. Make sure to post a link on your main page linking to the Mobile Page, and give it out to your customers as well.