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© The scientific sentence. 2010
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Technologie :
Smartphones
PSTN
PSTN stands for Public Switched Telephone Network .
The PSTN is the set of the world's circuit-switched
telephone networks that are operated by national, regional,
or local telephony operators, providing services for public
telecommunication.
The PSTN consists of telephone lines, fiber optic cables,
microwave transmission links, cellular networks,
communications satellites, and undersea telephone cables ,
all interconnected by switching centers, thus
allowing most telephones to communicate with
each other.
Originally a network of fixed-line analog telephone systems,
the PSTN is now almost entirely digital in its core network
and includes mobile and other networks, as well as fixed
telephones.
PSTN is the abbreviated term used for landline telephone
system. Another term commonly used for it is POTS,
which stands for Plain Old Telephone System, a
a way of naming the landline that is now old and
quite plain and flat when compared to new competitors
on the market.
This network was created mainly for analog
voice communication over cables that covered
countries and continents.
It is an improvement over the basic telephone
system discovered by Alexander Graham Bell
.
Alexander Graham Bell (1847 – 1922) was a Scottish-born
scientist, inventor, engineer, and innovator who is
credited with patenting the first practical telephone,
and founding the American Telephone and Telegraph
Company (AT&T) in 1885.
Mobile telephony emerged as the first alternative
to PSTN when it comes to voice communication.
Cellular communication (2G) allowed people to communicate
on the go while the PSTN allowed people to make and receive
calls only within the reach of the wires,
that is at home or in the office.
Nevertheless, the PSTN still remains the so far
unchallenged leader in call quality.
The PSTN has also kept its place at home
and in businesses for several reasons.
Until the recent past, many people had still
not adopted mobile telephony and could therefore
only be reached through their plain old
landline phone number.
Also, the PSTN remains the main carrier for Internet
connectivity in some parts of the world.
In any cases, VoIP is the more serious
competitor to PSTN operators than any
other technology by allowing people
to communicate locally and worldwide
for free or cheaper.
Think of Skype, WhatsApp and all the other VoIP
services and apps, which are even banned in some
countries as a means to protect the local and often
government-owned telcos.
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