Wi-Fi
A Wi-Fi enabled device such as a PC, game console, cell phone, MP3 player or PDA can connect to the Internet when within range of a wireless network connected to the Internet. The coverage of one or more interconnected access points — called a hotspot — can comprise an area as small as a single room with wireless-opaque walls or as large as many square miles covered by overlapping access points. Wi-Fi technology has served to set up mesh networks, for example, in London.[1] Both architectures can operate in community networks.[citation needed]
In addition to restricted use in homes and offices, Wi-Fi can make access publicly available at Wi-Fi hotspots provided either free of charge or to subscribers to various providers. Organizations and businesses such as airports, hotels and restaurants often provide free hotspots to attract or assist clients. Enthusiasts or authorities who wish to provide services or even to promote business in a given area sometimes provide free Wi-Fi access. Metropolitan-wide Wi-Fi (Muni-Fi) already has more than 300 projects in process.[2]
Wi-Fi also allows connectivity in peer-to-peer (wireless ad-hoc network) mode, which enables devices to connect directly with each other. This connectivity mode can prove useful in consumer electronics and gaming applications.
When wireless networking technology first entered the market many problems ensued for consumers who could not rely on products from different vendors working together. The Wi-Fi Alliance began as a community to solve this issue — aiming to address the needs of the end-user and to allow the technology to mature. The Alliance created the branding Wi-Fi CERTIFIED to reassure consumers that products will interoperate with other products displaying the same branding.
Many consumer devices use Wi-Fi. Amongst others, personal computers can network to each other and connect to the Internet, mobile computers can connect to the Internet from any Wi-Fi hotspot, and digital cameras can transfer images wirelessly.
Routers which incorporate a DSL-modem or a cable-modem and a Wi-Fi access point, often set up in homes and other premises, provide Internet-access and internetworking to all devices connected (wirelessly or by cable) to them. One can also connect Wi-Fi devices in ad-hoc mode for client-to-client connections without a router.
As of 2007 Wi-Fi technology had spread widely within business and industrial sites. In business environments, just like other environments, increasing the number of Wi-Fi access-points provides redundancy, support for fast roaming and increased overall network-capacity by using more channels or by defining smaller cells. Wi-Fi enables wireless voice-applications (VoWLAN or WVOIP). Over the years, Wi-Fi implementations have moved toward "thin" access-points, with more of the network intelligence housed in a centralized network appliance, relegating individual access-points to the role of mere "dumb" radios. Outdoor applications may utilize true mesh topologies. As of 2007 Wi-Fi installations can provide a secure computer networking gateway, firewall, DHCP server, intrusion detection system, and other functions.
Second life
http://secondlife.com/
Second Life® is a 3-D virtual world created by its Residents. Since opening to the public in 2003, it has grown explosively and today is inhabited by millions of Residents from around the globe.
From the moment you enter the World you'll discover a vast digital continent, teeming with people, entertainment, experiences and opportunity. Once you've explored a bit, perhaps you'll find a perfect parcel of land to build your house or business.
You'll also be surrounded by the Creations of your fellow Residents. Because Residents retain intellectual property rights in their digital creations, they can buy, sell and trade with other Residents.
The Marketplace currently supports millions of US dollars in monthly transactions. This commerce is handled with the inworld unit of trade, the Linden™ dollar, which can be converted to US dollars at several thriving online Linden dollar exchanges.
Welcome to the Second Life world. We look forward to seeing you inworld.
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From wiki
Second Life (abbreviated as SL) is an Internet-based virtual world launched in 2003, developed by Linden Research, Inc (commonly referred to as Linden Lab), which came to international attention via mainstream news media in late 2006 and early 2007.[4][5] A downloadable client program called the Second Life Viewer enables its users, called "Residents", to interact with each other through motional avatars, providing an advanced level of a social network service combined with general aspects of a metaverse. Residents can explore, meet other Residents, socialize, participate in individual and group activities, have virtual sex, and create and trade items (virtual property) and services from one another.Second Life is one of several virtual worlds that have been inspired by the cyberpunk literary movement, and particularly by Neal Stephenson's novel Snow Crash. The stated goal of Linden Lab is to create a world like the Metaverse described by Stephenson, a user-defined world in which people can interact, play, do business, and otherwise communicate.[6] Second Life's virtual currency is the Linden Dollar (Linden, or L$) and is exchangeable for real world currencies in a resident to resident marketplace facilitated by Linden Lab.[7] There is no fee for registering an account or participating in Second Life,
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