Part 26 About Isdn Modules - Tieline ViA User Manual

112 ViA User Manual v2.0
26 About ISDN Modules
ISDN stands for Integrated Services Digital Network. The Basic Rate Interface (BRI) of ISDN
consists of 2 bearer (B) channels at 64 kbps each and 1 data (D) channel at 16 kbps, i.e. (2B +D).
This can be provided over a 2 wire facility and the two B channels can be bonded together to form a
single 128kbps channel. The B channel can carry user information such as voice, video or data. The
D channel carries signaling information between a user and the network.
The codec has a single module slot supporting 2 B channels using the ViA USA ISDN module. This
delivers high quality mono or stereo audio over a single B channel using the Tieline Music
algorithm. If you have 2 B channels you can use one as a standby link, or configure higher
bandwidth mono or stereo connections using algorithms such as MusicPLUS, aptX Enhanced, or
MPEG.
Important Considerations
There are several considerations when using your codec in ISDN mode, including:
·
Will you operate within North America or other countries?
·
Will you use a single B channel or 2 B channels?
·
Which network are you using?
·
Is your ISDN line Point-to-Point or Point-to-Multipoint?
·
What are your directory numbers (DN)?
·
If you are in the US, what are your Service Profile ID (SPID) numbers?
·
What is your Multiple Subscriber Number (MSN) if you need to enter this outside North
America?
ISDN configuration is influenced by the country in which you operate. For example, a SPID does not
need to be entered into a Tieline codec for operation within Europe, but it does in North America.
U and S/T ISDN Interfaces
In North America the telephone company provides its BRI customers with a U interface. The U
interface is a two-wire (single pair) interface from the phone switch. It supports full-duplex data
transfer over a single pair of wires, therefore only a single device can be connected to a U interface.
The situation is different in Europe, the UK, most of Asia, Australia, Africa and parts of the Middle
East, where the phone company is allowed to supply the NT-1 and the customer is given an S/T
interface. The NT-1 is a relatively simple device that converts a 2-wire U interface into the 4-wire S/T
interface.
If you have an NT-1 device connected to the U interface line then you will require a Tieline ViA (ST)
ISDN module (S/T interface - model: TLISDNEUROVIA). If you don't have an NT-1 device installed
then the Tieline ViA (U) USA ISDN module (U interface - model: TLISDNUSAVIA) will be required.
You can ring your telecommunications provider to ask if you're not sure. Note: In Japan use the
Tieline ViA (ST) ISDN module.
Important Note: Tieline S/T ViA ISDN modules do not have internal terminating resistors.
When you connect terminating equipment such as a Tieline codec to an NT-1, 100 ohm
termination resistors must be connected between pins 3 and 6 and between pins 4 and 5
at the last socket on the ISDN line. Check your NT-1 device user manual as this may be
supported. Suppliers of electronic components sell suitable plugs with termination
resistors when required. Please note: U interface ISDN terminations do not require
terminating resistors.
© Tieline Pty. Ltd. 2017