R2511-HP MSR Router Series Interface Configuration Guide(V5)

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• Network terminal 1 (NT1) implements the functionality of the first layer in the OSI reference model,
such as subscriber-line transmission, loop test, D-channel competition.
• Network terminal 2 (NT2), or named intelligent network terminal, implements the functionality of
layers 1 through 3.
• Category-1 terminal equipment (TE1), or named ISDN standard terminal, is user equipment
compliant with the ISDN interface provisions. Digital phone-set is such an example.
• Category-2 terminal equipment (TE2), or named non-ISDN standard terminal equipment, refers to
the user equipment incompliant with the ISDN interface provisions.
• Terminal adapter (TA) implements the adaptation function so that TE2 can access a standard ISDN
interface.
Reference points include:
• R—Point between a non-ISDN equipment and TA.
• S—Point between a user terminal and NT2.
• T—Point between NT1 and NT2.
• U—Point between NT1 and line terminal.
Preparing for making configuration
Before making configuration, you should:
• Verify the type of the interface provided by your telecom service provider, whether it is ISDN BRI U
or ISDN BRI S/T. Despite that ITU-T I.411 has provided an ISDN user-network interface reference
model, there are some arguments in the position of the user-network dividing point. Some nations
adopt the U interface and some adopt the S/T interface depending on their needs. Identify the
interface type provided by your service provider before making a router purchase decision.
• Request for digital service. As ISDN can provide integrated services including both digital and
voice, you must request for an ISDN line allowing digital call service so that your router can make
digital communications.
• Select connection type, which can be a point-to-point connection or a point-to-multipoint connection
(optional). As ISDN supports semi-permanent connection, you can adopt the ISDN leased line in
the event that you adopt ISDN only for connecting two fixed points. Otherwise, you must select a
point-to-multipoint connection.
• Request for the delivery of Calling Line Identification (CLI) function (optional). With it, you can
implement calling number filtering on your ISDN line to reject some users from accessing the local
router and hence enhance the network security.
Configuration procedure
ISDN BRI interfaces are used for dialup purpose. For more information about ISBN BRI interface
configuration, see Layer 2—WAN Configuration Guide.
To configure an ISDN BRI interface:
Step Command Remarks
1. Enter system view.
system-view N/A
2. Enter ISDN BRI interface view.
interface bri number N/A