R0106-HP MSR Router Series Layer 2 - WAN Configuration Guide(V7)

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Configuring Q.931 call control parameters
To ensure successful call setup, make sure the call control parameters match the service provider's
settings.
Configuring B-channel selection
Efficient B-channel selection for calls improves call establishment efficiency and reduces call losses on
ISDN lines, especially PRI ISDN lines.
By default, ISDN interfaces on the device are operating as the user side, and they do not select
B-channels for calls. B-channel selection is done by the service provider switch.
To enable an ISDN interface to select B-channels, you have the following options:
• Use the isdn bch-local-manage command to enable non-exclusive B-channel selection. The
interface selects a preferred B-channel for a call, but it will use the B-channel selected by the peer
end when a selection conflict occurs.
• Use the isdn bch-local-manage exclusive command to enable exclusive B-channel selection. The
interface selects a preferred B-channel for a call, and it does not accept the B-channel selected by
the peer end when a selection conflict occurs.
IMPORTANT:
Configure exclusive B-channel selection only when the interface is the network side. If the interface is the
user side, exclusive B-channel selection will cause a call establishment failure when a B-channel selection
conflict occurs.
To enable B-channel selection on an ISDN interface:
Ste
p
Command Remarks
1. Enter system view.
system-view N/A
2. Enter ISDN BRI or PRI
interface view.
interface interface-type
interface-number
N/A
3. Enable the interface to
select B-channels for calls.
isdn bch-local-manage
[ exclusive ]
By default, B-channel selection is disabled.
The service provider switch selects B-channels
for calls.
4. Set a B-channel selection
method.
isdn bch-select-way
{ ascending | descending }
By default, an ISDN interface selects
B-channels in ascending order.
This command takes effect only when the isdn
bch-local-manage command is configured.
Configuring calling number verification for incoming calls
Calling number verification enables an ISDN interface to accept only calls from a specific calling party.
Call setup will fail in one of the following conditions:
• The calling number in the incoming SETUP message is not configured on the ISDN interface.
• The incoming SETUP message does not include a calling number.
To configure calling number verification for incoming calls: