Dial Up Internet Access
Dial-up Internet access is a form of Internet access that uses the
facilities of the public switched telephone network (PSTN) to establish
a dialed connection to an Internet service provider (ISP) via telephone
lines. The user's computer or router uses an attached modem to encode
and decode Internet Protocol packets and control information into and
from analogue audio frequency signals, respectively.
Dial-up connections to the Internet require no infrastructure other than
the telephone network and the modems and servers needed to make and
answer the calls. Where telephone access is widely available, dial-up
remains useful and it is often the only choice available for rural or
remote areas, where broadband installations are not prevalent due to low
population density, and high infrastructure cost. Dial-up access may
also be an alternative for users on limited budgets, as it is offered
free by some ISPs, though broadband is increasingly available at lower
prices in many countries due to market competition.
Dial-up requires time to establish a telephone connection (up to several
seconds, depending on the location) and perform configuration for
protocol synchronization before data transfers can take place. In
locales with telephone connection charges, each connection incurs an
incremental cost. If calls are time-metered, the duration of the
connection incurs costs.
Dial-up access is a transient connection, because either the user, ISP
or phone company terminates the connection. Internet service providers
will often set a limit on connection durations to allow sharing of
resources, and will disconnect the user—requiring reconnection and the
costs and delays associated with it. Technically inclined users often
find a way to disable the auto-disconnect program such that they can
remain connected for days.
A 2008 Pew Internet and American Life Project study states that only 10
percent of US adults still used dial-up Internet access. Reasons for
retaining dial-up access include lack of infrastructure and high
broadband prices. According to the United States Federal Communications
Commission (FCC), 6% used dial-up in 2010. By 2013, that number had
fallen to 3%.
Text is available under the Creative Commons Attribution-ShareAlike License; additional terms may apply.
Source: Wikipedia
PDF Version