Isdn Bri Recommendations - 3Com 3C10111C - NBX 100 - Modular Exp Base Installation Manual

ISDN BRI
Recommendations
When you work with the telephone company to install an ISDN BRI
circuit, 3Com recommends the parameters discussed in the following
sections.
Interface — The BRI connection supplied by the telephone company
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must terminate at an S/T interface. Connections terminating at the U
interface are not supported.
Point-to-Point and Point-to-Multipoint — Both point-to-point and
■
point-to-multipoint configurations are supported.
The appropriate TEI (Terminal Endpoint Identifier) must be entered
when configuring the BRI card. Typically, Automatic TEI assignment is
used on Point-to-Multipoint lines. For Point-to-Point lines, set the TEI
value to 0 (zero).
By default the system is configured to use Automatic TEI assignment.
Thus, if the line provided is Point-to-Point, this will typically mean the
TEI has to be set to 0 (zero) when configuring.
DDI/MSN Applications — For DDI/MSN, 3Com recommends that
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you order telephone numbers that easily fit in the NBX system
numbering plan. If possible, use 3 or 4 digit DDI/MSN codes, which
allow for simple dial plan implementation.
With 3 digit extensions 100-499, the last three digits of the
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DDI/MSN codes should be 100-499.
With 4 digit extensions 1000-4999, the last four digits of the
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DDI/MSN codes should be 1000-4999.
Supported Telephone Central Office Switch Protocols — NBX
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system ISDN BRI services support the ETSI central office switch
protocol.

ISDN BRI Recommendations

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