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Streamyx Technology
The technology which supports TM streamyx service is DSL. It stands
for Digital Subscriber Line. DSL is the next generation of Internet access technology.
A house or business with DSL has a data socket that looks like a phone socket. DSL
is a direct connection to the Internet that is always on. Technology has basically
enhanced the copper pair to enable data communication at rates of up to 2Mb/s.
The types of DSL technology chosen to support TM streamyx are ADSL, SDSL and Glite
DSL. ADSL stands for Asymmetrical Digital Subscriber Line. It allows you to simultaneously
access the net and use the phone or fax (at the same time). GLite DSL is similar to
ADSL but has lesser speed capability than full rate ADSL.
SDSL stands for Symmetrical Digital Subscriber Line. The different between ADSL and
SDSL is SDSL offers the customer symmetrical bandwidth upstream and downstream to
a customer (e.g. 1.5Mb/s SDSL Streamyx package offers the customer 1.5Mb/s downstream
speed as well as 1.5Mb/s upstream speed). Technologically, SDSL does not allow voice/fax
(PSTN) over the same copper.
An ADSL system basically consists of two parts ie. the Central Office (CO) which is
located at the exchange building and the other, Remote Termination Unit(RTU) at subscriber's
premise. The Central Office (CO) and Remote Terminal Unit(RTU) are connected via an
existing pair of copper telephone lines. Diagrams belows shows the TM direct(ADSL)
set up.
The Central Office (CO) for ADSL consists of two types of chassis. The first chassis
is the ADSL unit for modem cards and control card while the second chassis is for
the POTS (Plain Old Telephone Service) splitter. The Remote Terminal Unit (RTU) for
ADSL also consists of POTS splitter and ADSL modem.
A significant advantage of ADSL is its ability to seperate data traffic from voice
communications via one pair of existing copper wire. The voice communication is split
off from the data traffic by POTS splitter hence allowing uninterrupted telephony
services even if the ADSL fails. The diagram above shows the ADSL whereby the voice
communication is split and sent to the PSTN (Public Switched Telephone Network) while
the data traffic is sent to the broadband network.
While in the SDSL network set-up (where it only supports data), there will be no network
element of voice network (PSTN). The customer is connected directly into the broadband
network.
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