Configuring A Bri Interface To Supply Line Power; Configuring The Sliding Window Size On An Isdn Bri Interface - HP MSR Router Series Wan Access Configuration Manual

For energy efficiency, a network-side ISDN interface typically deactivates the physical layer when the
data link layer connection is disconnected. To maintain physical layer connectivity when the data link
connection is lost, enable persistent Layer 1 activation. This function prevents Q.921 from sending
deactivation requests to the physical layer.
Persistent Layer 1 activation can only maintain the active state of the physical layer. It does not activate
the physical layer if you enable it when the physical layer is inactive. In contrast, Q.921 attempts to set
up data link connections if you enable permanent Q.921 link connectivity when no data link connections
are present.
To enable persistent Layer 1 activation an ISDN BRI interface:
Step
1. Enter system view.
2. Enter ISDN BRI interface view.
3. Enable persistent Layer 1
activation.

Configuring a BRI interface to supply line power

You can configure only network-side BRI interfaces to supply line power to the terminal equipment.
NOTE:
Only ISDN BRI interfaces on the BSV module can operate on the network side.
You can perform this task only when no call is present.
To enable remote powering on an ISDN BRI interface:
Step
1. Enter system view.
2. Enter ISDN BRI interface
view.
3. Configure the interface to
supply line power.

Configuring the sliding window size on an ISDN BRI interface

Q.921 sends frames in order of their sequence numbers and requires an acknowledgment of each
transmitted frame. To improve transmission efficiency, Q.921 does not wait for a transmitted frame to be
acknowledged before it sends the next frame. Instead, it uses a sliding window mechanism for
transmission.
The sliding window mechanism enables Q.921 to send multiple continuous frames without waiting for
the acknowledgment of the previous frame. The sliding window size sets the maximum number of
unacknowledged frames. You can tune the size depending on the link status to maximize the throughput.
Command
system-view
interface bri interface-number
permanent-active
Command
system-view
interface bri interface-number
power-source
122
Remarks
N/A
N/A
By default, a BRI interface
deactivates the physical layer
when the Q.921 data link is
disconnected.
Remarks
N/A
N/A
By default, remote powering is
disabled.