Telos Zephyr Xstream - Manual (Page 339)

USER’S MANUAL
Appendix 7 – Ordering ISDN for Countries Using ETS300 (EURO ISDN) 327
Appendix 7: Ordering ISDN for ETS 300 (Euro ISDN)
This section applies to users in Europe and other countries where the Euro‐ISDN ETS 300
standard is supported (Europe, much of South America, Australia, South Africa, Mexico, etc).
Since there are virtually no options when ordering Euro ISDN, this section is probably not
needed, however we thought we could help by summarizing what you will require.
If you live in a country outside of North America that does not support Euro‐ISDN, your local
Telos Systems representative should be able to provide you with information about ordering
(and using) ISDN in your area. We assume you have read the description of ISDN in Section 7
(ISDN Basics) and are familiar with ISDN’s basic concepts. If you have not read that section,
doing so now will help you to better understand the information that follows.
On one ISDN BRI circuit, there are three simultaneous bi‐directional channels: two 64kbps
“bearer” or “B” channels for the transmission of user information and one 16kbps “data” or “D”
channel for call set‐up and status communication. That is why this is sometimes called 2B+D
service. You can use the B channels, but only the phone companies and equipment
manufacturers can usually use the D channel.
From the perspective of telephone network routing, each channel appears to be a separate line
with its own number and independent dial‐out capabilities. Since each has to be dialed or
answered separately, they appear to be “lines” to users also. We refer to a B channel as a “line”
on the Zephyr Xstream’s menu.
ISDN comes into your facility on two wires, just like plain old telephone service (POTS). There
the Telecom will install a NT1 (Network Termination) to provide you access to the S (4‐wire)
interface usually provided. You will be connecting this to the Zephyr Xstream’s top (8‐pin) jack.
Details, Details
In order to communicate accurately what it is you need, we think you should be familiar with
the vocabulary used to describe ISDN. As with anything, for best results, it helps to know what
you are talking about. For an in‐depth glossary of terminology please check Appendix 9 or the
Telos web site at
http://www.telos‐systems.com .
Names
We’ve seen Basic Rate Interface ISDN called by a number of names. The term “S∅” is
sometimes used as a technical term for ISDN BRI. Of course, the term “BRI” is also used, mostly
by Telecom technicians. The most common term we’ve seen in Europe is “ISDN‐2”.
Multiple Subscriber Numbers (MSN)
These are simply your phone numbers. The number of digits will vary depending on your area.
Normally each ISDN BRI circuit will have three MSNs. MSNs are optional, and do not need to be
entered in the Telos Equipment.