By Raul Bernardino
Introduction:
Nowadays, the networks and internet technology is growing faster.
The companies, organizations, governments, and the institutions are using these
technologies to connect, communicate, coordinate and collaborate (four sees or 4Cs)
in their information sharing among themselves or shared them between the public
audiences within cross border information platforms’. The internet
communication facility, allows everyone to share their expertise, experiences, knowledge,
information, and also to be able to interact within one and another without having
any limitation; the accessibility and reliability of the data sharing
information and knowledge over networks are to ensure that everyone has same
opportunity to access and convene same bits of the information. The information
and knowledge has to be reliable and accessible at any time and from anywhere. Therefore,
it is important enabling this trend of connectivity’s within an existing
networks with internet telephony.
“The real time interactive audio and video over internet is called
internet telephone or internet video call. This is similar to the traditional
telephone call which is using telephone circuit and switches”, Kurose
J. and Ross K., (2010, P. 627). For
example, establishes voice or video calls from PC to PC or from PC to the
normal telephone switches voice calls. Other examples are using Skype to call
from PC to PC or PC to normal telephone networks, net meeting, go to meeting, and
other polycom products such as video and audio conferences.
The PBX stands for private
branch exchange. That is a telephone system, where within one office shares
the public switched telephone network
(PSTN) lines. It can be one or more telephone lines that are coming from telecom
provider to the office and the office is sharing those resources among the end
users within one office or between branch offices. For instance, four PSTN
lines from telecom operator to the office; these PSTN lines can be divided into
one dedicates line for the official fax mail machine and other three PSTN lines
are connected through the PBX trunks in
which to ne shared within the rest of the team. One of PBX trunk shows in the
below picture:
Each team member can be reached by extension phones. The extension
phones, usually has two to four digits depends on the PBX configuration. The
extension phones are also connected to the PBX trunks. One of extension as it
shows in the below picture:
The extension phones are enabling team member to make a communication
internally or establish a communication within branch offices without have any
cost.
The PBX is referring to the PABX and EPABX. The PABX stands for private automatic branch exchange while EPABX
stands electronic private automatic
branch exchange.
Since 1990, there were developments in the PBX technology. They
are focusing on the packet switching. The companies, organization, government,
and institutions are using packet switched for the data communication. It
attempts to use as telephone calls and later it calls VoIP (Voice over IP). The
ISDN also another development in that time, whereas can make a conference call,
call forwarding, and caller ids.
The technology between LAN and traditional telephone networks are
PBX and router. These two technologies can become exchange switch from normal
telephone call to the VoIP or from VoIP to normal telephone network. For instance, by is using the Skype whereas
to make a call from PC to PC or from PC to normal telephone network. The PBX
has to add digital trunks in which to enable the connection between router and voice
lines. As it shows in below diagram:
The PBX functions are as follows: To establish a communication
between two parties or more and it is including ensuring that the line is free
or busy. To maintain the connection as it require. To disconnect the connection
as it require. To provide the information’s such as telephone bills.
References list:
1. Kurose, J.F. & Ross, K.W. (2010) Computer Networking: A Top-Down Approach.
5th ed. Boston:
Addison Wesley
2. Business
telephone system, [Online]. Available from: http://en.wikipedia.org/wiki/Private_branch_exchange#Private_branch_exchange
(Accessed: 6 July 2013)
3. Cisco
3640 Router - PBX Interoperability: Nortel Meridian Option 11 Rel. 24 PBX with
Analog FXS and FXO interfaces to an MGCP Gateway, [Online]. Available from: http://www.cisco.com/en/US/docs/voice_ip_comm/cucme/pbx/interop/notes/210514nt.pdf
(Accessed: 6 July 2013)
