Wireless

Wireless communication is the transfer of information between two or more points that are not connected by an electrical conductor.

The most common wireless technologies use radio. With radio waves distances can be short, such as a few meters for television or as far as thousands or even millions of kilometers for deep-space radio communications. It encompasses various types of fixed, mobile, and portable applications, including two-way radios, cellular telephones, personal digital assistants (PDAs), and wireless networking. Other examples of applications of radio wireless technology include GPS units, garage door openers, wireless computer mice, keyboards and headsets, headphones, radio receivers, satellite television, broadcast television and cordless telephones.

Somewhat less common methods of achieving wireless communications include the use of other electromagnetic wireless technologies, such as light, magnetic, or electric fields or the use of sound.

It should be noted that the term wireless has been used twice in communications history, with slightly different meaning. It was initially used from about 1890 for the first radio transmitting and receiving technology, as in wireless telegraphy, until the new word radio replaced it around 1920. The term was revived in the 1980s and 1990s mainly to distinguish digital devices that communicate without wires, such as the examples listed in the previous paragraph, from those that require wires. This is its primary usage today.

Wireless (disambiguation)

Wireless refers to the transfer of information signals without using wires. The term may also refer to:

Electronic communications

Music

Books

Service

Service may refer to:

Acts of service

Religion

Service (economics)

In economics, a service is an intangible commodity. That is, services are an example of intangible economic goods.

Service provision is often an economic activity where the buyer does not generally, except by exclusive contract, obtain exclusive ownership of the thing purchased. The benefits of such a service, if priced, are held to be self-evident in the buyer's willingness to pay for it. Public services are those, that society (nation state, fiscal union, regional) as a whole pays for, through taxes and other means.

By composing and orchestrating the appropriate level of resources, skill, ingenuity, and experience for effecting specific benefits for service consumers, service providers participate in an economy without the restrictions of carrying inventory (stock) or the need to concern themselves with bulky raw materials. On the other hand, their investment in expertise does require consistent service marketing and upgrading in the face of competition.

Characteristics

Service (business)

Business services are a recognisable subset of Economic services, and share their characteristics. The essential difference is that Business are concerned about the building of Service Systems in order to deliver value to their customers and to act in the roles of Service Provider and Service Consumer.

Service definition

The generic clear-cut, complete, concise and consistent definition of the service term reads as follows:

A service is a set of one time consumable and perishable benefits

Voice over IP

Voice over IP (VoIP) is a methodology and group of technologies for the delivery of voice communications and multimedia sessions over Internet Protocol (IP) networks, such as the Internet. Other terms commonly associated with VoIP are IP telephony, Internet telephony, broadband telephony, and broadband phone service.

The term Internet telephony specifically refers to the provisioning of communications services (voice, fax, SMS, voice-messaging) over the public Internet, rather than via the public switched telephone network (PSTN). The steps and principles involved in originating VoIP telephone calls are similar to traditional digital telephony and involve signaling, channel setup, digitization of the analog voice signals, and encoding. Instead of being transmitted over a circuit-switched network, however, the digital information is packetized, and transmission occurs as IP packets over a packet-switched network. Such transmission entails careful considerations about resource management different from time-division multiplexing (TDM) networks.