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A phrase used to describe a type of website hosting platform that is used to serve an electronic commerce website. Ecommerce hosting differs from standard Web hosting in that a number of features and functionalities are required to manage and run a commercial website. This includes SSL, database support, shopping cart software, payment processing services, and additional ecommerce software and security initiatives. Ecommerce hosting is designed to basically provide entrepreneurs and businesses with all the tools and services required for them to set-up, manage and conduct an ecommerce business.

Ecommerce hosting is an option offered by many Web hosting service providers. In addition to supplying ecommerce functionality, they will also provide Web space (a Web server) to host your website, an email server or email support, technical support and other standard Web hosting features for businesses.

Network topologies

In computer networking, topology refers to the layout of connected devices. This article introduces the standard topologies of networking.

TOPOLOGY IN NETWORK DESIGN

Think of a topology as a network's virtual shape or structure. This shape does not necessarily correspond to the actual physical layout of the devices on the network. For example, the computers on a home LAN may be arranged in a circle in a family room, but it would be highly unlikely to find a ring topology there.

Network topologies are categorized into the following basic types:

·         bus

·         ring

·         star

·         tree

·         mesh

More complex networks can be built as hybrids of two or more of the above basic topologies.

BUS TOPOLOGY

Bus networks (not to be confused with the system bus of a computer) use a common backbone to connect all devices. A single cable, the backbone functions as a shared communication medium that devices attach or tap into with an interface connector. A device wanting to communicate with another device on the network sends a broadcast message onto the wire that all other devices see, but only the intended recipient actually accepts and processes the message.

Ethernet bus topologies are relatively easy to install and don't require much cabling compared to the alternatives. 10Base-2 ("ThinNet") and 10Base-5 ("ThickNet") both were popular Ethernet cabling options many years ago for bus topologies. However, bus networks work best with a limited number of devices. If more than a few dozen computers are added to a network bus, performance problems will likely result. In addition, if the backbone cable fails, the entire network effectively becomes unusable.

Illustration - Bus Topology Diagram

RING TOPOLOGY

In a ring network, every device has exactly two neighbors for communication purposes. All messages travel through a ring in the same direction (either "clockwise" or "counterclockwise"). A failure in any cable or device breaks the loop and can take down the entire network.

To implement a ring network, one typically uses FDDI, SONET, or Token Ring technology. Ring topologies are found in some office buildings or school campuses.

Illustration - Ring Topology Diagram

STAR TOPOLOGY

Many home networks use the star topology. A star network features a central connection point called a "hub" that may be a hub, switch orrouter. Devices typically connect to the hub with Unshielded Twisted Pair (UTP) Ethernet.

Compared to the bus topology, a star network generally requires more cable, but a failure in any star network cable will only take down one computer's network access and not the entire LAN. (If the hub fails, however, the entire network also fails.)

Illustration - Star Topology Diagram

TREE TOPOLOGY

Tree topologies integrate multiple star topologies together onto a bus. In its simplest form, only hub devices connect directly to the tree bus, and each hub functions as the "root" of a tree of devices. This bus/star hybrid approach supports future expandability of the network much better than a bus (limited in the number of devices due to the broadcast traffic it generates) or a star (limited by the number of hub connection points) alone.

Illustration - Tree Topology Diagram

Mesh Topology

Mesh topologies involve the concept of routes. Unlike each of the previous topologies, messages sent on a mesh network can take any of several possible paths from source to destination. (Recall that even in a ring, although two cable paths exist, messages can only travel in one direction.) Some WANs, most notably the Internet, employ mesh routing.

A mesh network in which every device connects to every other is called a full mesh. As shown in the illustration below, partial mesh networks also exist in which some devices connect only indirectly to others.

Illustration - Mesh Topology Diagram

SUMMARY

Topologies remain an important part of network design theory. You can probably build a home or small business computer network without understanding the difference between a bus design and a star design, but becoming familiar with the standard topologies gives you a better understanding of important networking concepts like hubs, broadcasts, and routes.

Bricks aNd cLicks

 

MEANING

A sales model that utilizes both traditional stores (bricks) and Internet trading (clicks).

 

ORIGIN

This business model, also known as 'clicks and mortar' or 'clicks and bricks', began to be used in the 1990s. The rise of the Internet opened up opportunities for online trading. Initially this was utilized by companies whose primary business was Internet-based - the so-called 'clicks' companies. Established trading companies followed when it became clear that businesses didn't have to be limited to either traditional stores or online trading, but could make use of both. Questions like this were being asked of business leaders:

"Do you work for a bricks company, a clicks company, or a bricks and clicks company?"

(from The Times, September 1999, reporting a talk by Andy Grove, chairman of Intel Corporation to the UK's CBI conference)

Many companies decided that 'bricks' and 'clicks' alone were only appropriate for niche markets and most opted for a mixture of both. This resulted in what was described as the "rush to the middle". In practice there are now very few companies that aren't 'bricks and clicks'. Only quite small local shops have no online presence. Most companies that do trade online aren't exclusively 'clicks'. Some trade exclusively in digital products that require no buildings, but there are warehousing and delivery facilities behind businesses that trade in material goods

Typical of the established companies that were early adopters of 'bricks and clicks' were supermarkets, who offered their customers the option of ordering online and having their groceries delivered from central warehousing.

The rhyming nature of the phrase is in keeping with the fashion amongst journalists and advertisers, who like a memorable phrase for people to latch on to; for example, 'beef and reef', surf and turf' etc.

worLd wiDe wEb

Probably the World Wide Web saved the net. Not only did it change its appearance, it made it possible for pictures and sound to be displayed and exchanged.

The web had some important predecessors, perhaps the most significant of these being Ted Nelson's Xanadu project, which worked on the concept of Hypertext - where you could click on a word and it would take you somewhere else. Ted Nelson envisaged with Xanadu a huge library of all the worlds' information. In order to click on hyperlinks, as they were called, Douglas Engelbart invented the mouse, which was to later become a very important part of personal computers. So the idea of clicking on a word or a picture to take you somewhere else was a basic foundation of the web.

Another important building block was the URL or Uniform Resource Locator. This allowed you a further option to find your way around by naming a site. Every site on the worldwide web has a unique URL (such as www.nethistory.info).

The other feature was Hypertext Markup Language (html), the language that allowed pages to display different fonts and sizes, pictures, colours etc. Before HTML, there was no such standard, and the "GUIs we talked about before only belonged to different computers or different computer software. They could not be networked.

It was Tim Berners Lee who brought this all together and created the World Wide Web. The first trials of the World Wide Web were at the CERN laboratories (one of Europe's largest research laboratories) in Switzerland in December 1990. By 1991 browser and web server software was available, and by 1992 a few preliminary sites existed in places like University of Illinois, where Mark Andreesen became involved. By the end of 1992, there were about 26 sites.

The first browser which became popularly available to take advantage of this was Mosaic, in 1993. Mosaic was as slow as a wet week, and really didn't handle downloading pictures well at all - so the early world wide web experience with Mosaic, and with domestic modems that operated at one sixths of current modem speeds at best, were pretty lousy and really didn't give much indication of the potential of this medium. 

On April 30, 1993 CERN's directors made a statement that was a true milestone in Internet history. On this day, they declared that WWW technology would be freely usable by anyone, with no fees being payable to CERN. This decision - much in line with the decisions of the earlier Internet pioneers to make their products freely available - was a visionary and important one. 

The browser really did begin to change everything. By the end of 1994 there were a million browser copies in use - rapid growth indeed!! 

In the same year Marc Andreesen founded Netscape Corporation, and the World Wide Web Consortium, which administers development of Word Wide Web standards, was formed by Tim Berners Lee.

Then we really started to see growth. Every year from 1994 to 2000, the Internet saw massive growth, the like of which had not been seen with any preceding technology. The Internet era had begun.

The first search engines began to appear in the mid 1990s, and it didn't take long for Google to come on the scene, and establish a dominant market position.

In the early days, the web was mainly used for displaying information. On line shopping, and on line purchase of goods, came a little bit later. The first large commercial site was Amazon, a company which in its initial days concentrated solely on book markets. The Amazon concept was developed in 1994, a year in which some people claim the world wide web grew by an astonishing 2300 percent! Amazon saw that on line shopping was the way of the future, and chose the book market as a field where much could be achieved.

By 1998 there were 750,000 commercial sites on the world wide web, and we were beginning to see how the Internet would bring about significant changes to existing industries. In travel for instance, we were able to compare different airlines and hotels and get the cheapest fares and accommodation - something pretty difficult for individuals to do before the world wide web. Hotels began offering last minute rates through specially constructed websites, thus furthering the power of the web as a sales medium. 

And things went even further - in some fields of travel, individuals would outline where they wanted to travel to and from, and travel companies would then bid for the business. All these developments rapidly changed the way traditional markets worked. In some industries, the world would never be the same again.

alamak!!! due anta exsgment da dekat!!!!!!

pejam celik, pejam celik... da nak kne hantar exsgment.. ape pun xbuat lagi.. sape nak tlg????