© COPYRIGHT OF ASUSCOM NETWORK INC.
Chapter 1 Introduction
The proliferation of PCs and LANs with bandwidth intensive applications has generated
a powerful demand for high-speed connections. The worldwide standardization of
ISDN, combined in many countries with its growing availability and falling cost make it a
natural choice for enhancing data throughput.
ISDNL
TA-200 terminal adapters provide high-performance solutions for
Internet
INK ™
access, file transfer, remote access service, and running existing modem
applications
through the ISDN network.
ISDNL
TA-200 External Terminal Adapters
INK™
There are two ISDN interface options of ISDNL
external TA (Terminal Adapter):
INK™
ST or U interface. If you purchased the ST interface terminal adapters (TA-200ST and
TA-200ST-D), you need an ISDN NT1 device to connect to the ISDN exchange (the
NT1 box should normally be provided by your phone company). If you purchased the
U interface terminal adapters (TA-200U and TA-200U-D), they can directly connect to
the ISDN switch.
The TA-200ST and TA-200U devices support two a/b (POTS)
analog ports with connection through a supplied RJ-11 extension cable (in the UK
adapters are supplied for the standard BT connections).
The TA-200ST-D and TA-
200U-D models provide the data port connection without a/b (POTS) ports.
All of the current analog devices, including telephone set, G3 fax, answering machine,
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modem, and PBX trunk line can be connected to the a/b port (RJ-11 jack/POTS ports)
.
The data transmission rate can be up to 64 Kbps while a normal analog communication
is taking place on on-line, or up to 128 Kbps through Multilink PPP connection using
both digital lines.
Why ISDN?
The ISDN (Integrated Services Digital Network) is the standard for carrying both data
and voice simultaneously.
ISDN BRI (Basic Rate Interface) line provides two B-
Channels for voice or data transmission.
Each B-Channel can provide data
transmission of up to 64 Kbps. The ISDN network uses the same transmission lines
as the existing analog telephone network, but uses a digital signal and higher
bandwidth between the central office (telephone company) and the customer. ISDN is
not only much faster than standard modems; it also provides an extremely reliable and
stable digital connection.
Please note that the POTS analogue ports on the TA200 device, in common with most PBX, terminal
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adapters and fax switches, supply a reduced ring voltage. That is to say the ring voltage is lower than
that provided on a standard PSTN phone line. This does mean that in very rare circumstances some
analogue equipment may not be able to detect an incoming call.
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