Chapter 6 Configuring Additional ISDN Support
ISDN configuration includes the following tasks:
• Configuring the ISDN signaling type.
• Configuring the negotiation parameters of ISDN Layer 3.
• Configuring the SPID parameters of the National (NI) ISDN protocol.
6.1 Configuring ISDN Signaling Type
By default, DSS1 signaling is used on ISDN interfaces. You can configure:
• DSS1 on BRI, E1 PRI, and T1 PRI interfaces
• NI (National ISDN), NTT, ANSI, and ATT 5ESS (Lucent 5E) on BRI interfaces
• NTT, ANSI, and ATT 5ESS (Lucent 5E) are configured with the negotiation
commands of Layer 3 within the DSS1 protocol.
6.2 Configuring the Negotiation Parameters of ISDN Layer 3
6.2.1 NTT Protocol
Table 6-1 Required NTT Protocol Commands
Operation Command
Disable the Sending-Complete
Information Element in the Setup message
undo isdn sending-complete
Disable the SETUP ACK messages if the received SETUP
messages in data service calls do not carry the called number
information.
isdn ignore callednum
Table 6-2 Optional NTT Protocol Commands
Operation Command
Configure the SETUP message to ignore the high-level
compatibility information unit when a data call is initiated.
isdn ignore hlc
Restore the SETUP message.
undo isdn ignore hlc
Configure the SETUP message to ignore the low-level
compatibility information unit when a data call is initiated.
isdn ignore llc
Restore the SETUP message.
undo isdn ignore llc
Configure the router to wait for CONNECT ACK message
replies from the connected exchange until switching to the
ACTIVE state.
isdn waitconnectack
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