HABLANDO EN WIRELESS   
THE WORLD OF WIRELESS
applications and technologies, and its alphabet soup of acronyms, can
be a confusing place. The bets your company makes on wireless technology
will likely depend on where you work; they could also depend on how many
different technologies your customers require you to support. Here they
are.
3G (third generation) An industry
term used to describe the next, still-to-come generation of wireless applications.
It represents a move from circuit-switched communications (where a device
user has to dial in to a network) to broadband, high-speed, packet-based
wireless networks (which are always "on"). The first generation
of wireless communications relied on analog technology (see Analog), followed
by digital wireless communications. The third generation expands the digital
premise by bringing high-speed connections and increasing reliability.
802.11 A family of wireless specifications
developed by a working group of The Institute of Electrical and Electronics
Engineers. These specifications are used to manage packet traffic over
a network and ensure that packets do not collide-which could result in
loss of data-while traveling from their point of origin to their destination
(that is, from device to device).
AMPS (advanced mobile phone service) A
term used for analog technologies, the first generation of wireless technologies.
Analog Radio signals that are converted
into a format that allows them to carry data. While cellular phones and
other wireless devices still use analog in geographic areas where there
is little or no coverage by digital networks, analog will eventually give
way to faster digital networks, analysts say.
Bandwidth The size of a network "pipe"
or channel for communications in wired networks. In wireless, it refers
to the range of available frequencies that can carry a signal.
BlackBerry Two-way wireless device,
made by Waterloo, Ontario-based Research in Motion, that allows users
to check e-mail and voice mail (translated into text), as well as page
other users via a wireless network service. Also known as a RIM device,
it has a miniature qwerty keyboard for users to type their messages. It
uses the SMS protocol (see SMS). BlackBerry users must subscribe to a
wireless service that allows for data transmission.
Bluetooth A short-range wireless
specification that allows for radio connections between devices within
a 30-foot range of each other. The name comes from 10th-century Danish
King Harald Blåtand (Bluetooth), who unified Denmark and Norway.
CDMA (code division multiple access) U.S.
wireless carriers, such as Sprint PCS and Verizon, use CDMA to allocate
bandwidth for users of digital wireless devices. CDMA distinguishes between
multiple transmissions carried simultaneously on a single wireless signal.
It carries the transmissions on that signal, freeing network room for
the wireless carrier and providing interference-free calls for the user.
Several versions of the standard are still under development. CDMA promises
to open up network capacity for wireless carriers and improve the quality
of wireless messages and users' access to the wireless airwaves. It's
an alternative to GSM, which is popular in Europe and Asia (see GSM).
CDPD (cellular digital packet data) Telecommunications
companies can use CDPD to transfer data on unused cellular networks to
users. If one section, or "cell," of the network is overtaxed,
CDPD automatically allows for the reallocation of resources.
Cellular Technology that sends analog
or digital transmissions from transmitters that have areas of coverage
called cells. As a user of a cellular phone moves between transmitters
from one cell to another, the user's call travels from transmitter to
transmitter uninterrupted.
Circuit switched Used by wireless
carriers, this method lets a user connect to a network or the Internet
by dialing in, such as with a traditional phone line. It's a dial-in Internet
service provider for wireless device users. Circuit-switched connections
can be slow and unreliable compared with packet-switched networks, but
for now circuit-switched networks are the primary method of Internet and
network access for wireless users in the United States (see Packet-switched
network).
Dual-band mobile phone Phones that
support both analog and digital technologies by picking up analog signals
when digital signals fade. Most mobile phones are not dual-band.
EDGE (enhanced data GSM environment) A
faster version of the GSM standard. It is faster than GSM because it can
carry messages using broadband networks that employ more bandwidth than
standard GSM networks (see GSM).
FDMA (frequency division multiple access)
An analog standard that lets multiple users access a group of radio
frequency bands and eliminates interference of message traffic.
Frequency hopping spread spectrum
A method by which a carrier spreads out packets of information (voice
or data) over different frequencies. For example, a phone call is carried
on several different frequencies so that when one frequency is lost another
picks up the call without breaking the connection.
GPRS (general packet radio service) A
technology that sends packets of data across a wireless network at speeds
of up to 114Kbps. It is a step up from the circuit-switched method; wireless
users do not have to dial in to networks to download information. With
GPRS, wireless devices are always on-they can receive and send information
without dial-ins. GPRS is designed to work with GSM.
GSM (global system for mobile communications)
A standard for how data is coded and transferred through the wireless
spectrum. The European wireless standard also used in Asia, GSM is an
alternative to CDMA. GSM digitizes and compresses data and sends it down
a channel with two other streams of user data. The standard is based on
time division multiple access (see TDMA).
HDML (handheld device markup language)
It uses hypertext transfer protocol (HTTP, the underlying protocol
for the Web) to allow for the display of text versions of webpages on
wireless devices. Unlike wireless markup language (see WML), HDML is not
based on XML. HDML also does not allow developers to use scripts, while
WML employs its own version of JavaScript. Phone.com, now part of Openwave
Systems, developed HDML and offers it free of charge. Website developers
using HDML must recode their webpages in this language to tailor them
for the smaller screens of handhelds.
I-Mode
A wildly popular service in Japan for transferring packet-based data to
handheld devices. I-Mode is based on a compact version of HTML and does
not use WAP (see WAP), setting it apart from other widely used transmission
methods. I-Mode's creator, NTT DoCoMo of Tokyo, agreed in November 2000
to pay $9.8 billion to buy 16 percent of AT&T Wireless. Since then,
AT&T Wireless has talked about bringing I-Mode to the United States
by the end of 2001-a daunting prospect that requires the rebuilding of
U.S. wireless networks, analysts say. DoCoMo is developing a version of
I-Mode that supports the WAP standard.
Integrated Digital Enhanced Network (iDEN)
A technology that allows users to access phone calls, two-way radio
transmissions, paging and data transmissions from one wireless device.
Developed by Motorola, iDEN is based on TDMA. Services based on the technology
are available in North America (offered by Nextel), South America and
parts of Asia (see TDMA).
Kbps (kilobits per second) A measurement
of bandwidth in the United States.
Packet A chunk of data that is sent
over a network, whether it's the Internet or wireless network. Packet
data is the basis for packet-switched networks, which are under development
in the United States as a faster, more reliable method of transferring
wireless data than a circuit-switched network. Packet-switched networks
eliminate the need to dial in to send or receive information because they
are "always on," transferring data without the need to dial.
The packets that hold data depend on the size of the data involved; "chunks"
are broken down into an efficient size for routing. Each of these packets
has a separate number and carries the Internet address for which it is
destined.
Packet-switched network Networks
that transfer packets of data (see Packet).
PCS (personal communications services)
An alternative to cellular, PCS works like cellular technology because
it sends calls from transmitter to transmitter as a caller moves. But
PCS uses its own network, not a cellular network, and offers fewer "blind
spots"-areas in which access to calls is not available-than cellular.
PCS transmitters are generally closer together than their cellular counterparts.
PDA (personal digital assistant) Mobile,
handheld devices-such as the Palm series and Handspring Visors-that give
users access to text-based information. Users can synchronize their PDAs
with a PC or network; some models support wireless communication to retrieve
and send e-mail and get information from the Web.
Radio frequency devices These devices
use radio frequencies to transmit data. One typical use: a bar code scanner
gathers information about products in stock or ready for shipment in a
warehouse or distribution center and sends them to a database or ERP system.
Satellite phone Phones that connect
callers via satellite. The idea behind a satellite phone is to give users
a worldwide alternative to sometimes unreliable digital and analog connections.
So far, such services have proven very costly and have appealed to few
users aside from, for example, the crews at deep-sea oil rigs with phones
configured to connect to a satellite service.
Smart phone A combination of a mobile
phone and a PDA, smart phones allow users to converse as well as perform
tasks, such as accessing the Internet wirelessly and storing contacts
in databases. Smart phones have a PDA-like screen. As smart phone technology
matures, some analysts expect these devices to prevail among wireless
users. A PDA equipped with an Internet connection could be considered
a smart phone. Ericsson, Nokia and Motorola also make smart phones.
SMS (short messaging service) A service
through which users can send text-based messages from one device to another
(see BlackBerry). The message-up to 160 characters-appears on the screen
of the receiving device. SMS works with GSM networks
TDMA (time division multiple access) This
protocol allows large numbers of users to access one radio frequency by
allocating time slots for use to multiple voice or data calls. TDMA breaks
down data transmission, such as a phone conversation, into fragments and
transmits each fragment in a short burst, assigning each fragment a time
slot. With a cell phone, the caller would not detect this fragmentation.
Whereas CDMA (which is used more frequently in the United States) breaks
down calls on a signal by codes, TDMA breaks them down by time. The result
in both cases: increased network capacity for the wireless carrier and
a lack of interference for the caller. TDMA works with GSM and digital
cellular services.
WAP (wireless application protocol) WAP
is a set of protocols that lets users of mobile phones and other digital
wireless devices access Internet content, check voice mail and e-mail,
receive text of faxes and conduct transactions. WAP works with multiple
standards, including CDMA and GSM. Not all mobile devices support WAP,
but IDC (a sister company to CIO's publisher, CXO Media) projects that
more than 1.3 billion wireless Internet users will have WAP-capable devices
in their hands by 2004.
WASP (wireless application service provider)
These vendors provide hosted wireless applications so that companies
will not have to build their own sophisticated wireless infrastructures.
Vendors include Etrieve and Wireless Knowledge.
WCDMA (wideband CDMA) A third-generation
wireless technology under development that allows for high-speed, high-quality
data transmission. Derived from CDMA, WCDMA digitizes and transmits wireless
data over a broad range of frequencies. It requires more bandwidth than
CDMA but offers faster transmission because it optimizes the use of multiple
wireless signals-not just one, as with CDMA.
Wireless LAN It uses radio frequency
technology to transmit network messages through the air for relatively
short distances, like across an office building or college campus. A wireless
LAN can serve as a replacement for or extension to a wired LAN.
Wireless spectrum A band of frequencies
where wireless signals travel carrying voice and data information. Wireless
carriers are bidding at Federal Communications Commission auctions on
slivers of airwaves through which they will ultimately be able to send
third-generation communications. The auctions, which began in December
2000 in the United States and already occurred in several European nations,
will give providers access to new pieces of the spectrum that will allow
them to move to third-generation services. More auctions relevant to 3G
communications are on tap (see 3G).
WISP (wireless Internet service provider)
A vendor that specializes in providing wireless Internet access.
WML (wireless markup language) A version
of HDML, WML is based on XML and will run with its own version of JavaScript.
Wireless application developers use WML to repurpose content for wireless
devices.
El retorno de la inversión en entrenamiento y capacitación de equipos gerenciales es normalmente exponencial y en minutos. Vincent Peale.
          
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