2016年12月英语六级阅读理解100篇：eBay购物
eBayeBay is a global phenomenon-the world's largest garage sale, online
shopping center, car dealer and auction site with 147 million registered users
in 30 countries as of March 2005. You can find everything from encyclopedias to
olives to snow boots to stereos to airplanes for sale. And if you stumble on it
before the eBay overseers do, you might even find a human kidney or a virtual
date.
eBay Basics
eBay is, first and foremost. an online auction site. You can browse through
categories like Antiques, Boats, Clothing & Accessories, Computers &
Networking,Jewelry & Watches and Video Games. When you see something you
like, you click on the auction title and view the details, including pictures,
descriptions,payment options and shipping information.
If you place a bid on an item,you enter a contractual agreement to buy it
if you win the auction. All auctions have minimum starting bids, and some have a
reserve price-a secret minimum amount the seller is willing to accept for the
item. If the bidding doesn't reach the reserve price, the seller doesn't have to
partwith the item. In addition to auctions, you can find tons of fixed-price
items on eBay that make shopping there just like shopping at any other online
marketplace. You see what you like, you buy it, you pay for it and you wait for
it to arrive at your door.
You can pay for an item on eBay using a variety of methods, including money
order, cashier's check, cash, personal check and electronic payment services
like PayPal and BidPay. It's up to each seller to decide which payment methods
he'll accept.
Just as you can buy almost anything on eBay, you can sell almost anything,
too. Using a simple listing process, you can put all of the junk in your
basement up for sale to the highest bidder. When you sell an item on eBay,you
pay listing fees and turn over a percentage of the final sale price to eBay.
Once you register (for free) with eBay, you can access all of your eBay
buying and selling activities in asingle location called "My eBay."
eBay Infrastructure
A series of service disruptions in 1999 caused real problems for eBay's
business. Over the course of threedays, overloaded servers intermittently shut
down, meaning users couldn't check auctions, place bids or complete transactions
during that period. Buyers, sellers and eBay were very unhappy, and a complete
restructuring of eBay's technological architecture Followed.
In 1999, eBay was one massive database server and a few separate systems
running the search function. In 2005, eBay is about 200 database servers and 20
search servers.
The architecture is a type of grid computing that allows for both error
correction and growth. With the exception of the search function, everything
about eBay can actually run on approximately 50 servers-Web servers,application
servers and data-storage systems. Each server has between 6 and 12
microprocessors. These50 0r so servers run separately, but they talk to each
other,so everybody knows if there is a problem somewhere. eBay can simply add
servers to the grid as the need arises.
While the majority of the site can run on 50 servers,eBay has four times
that.The 200 servers are housed in sets of 50 in four locations,all in the
United States. When you're using eBay, you may be talking to anyone of those
locations at any time-they all store the same data. If one of the systems
crashes. there are three others to pick up the slack.
When you're on the eBay Web site and you click on a listing for a Persian
rug, your computer talks to Web servers, which talk to application servers,
which pull data from storage servers so you can find out what the latest bid
price is and how much time is left in the auction. eBay has local partners in
many countries who deliver eBay's static data to cut down on download time, and
there are monitoring systems in 45 cities around the world that constantly scan
for problems in the network.
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