H3C MSR810, Command Reference Manual

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Use
undo isdn pri-slipwnd-size
to restore the default.
Syntax
isdn pri-slipwnd-size window-size
undo isdn pri-slipwnd-size
Default
The sliding window size is 7 on ISDN PRI interfaces.
Views
ISDN interface view
Predefined user roles
network-admin
Parameters
window-size
: Specifies a sliding window size in the range of 5 to 64.
Usage guidelines
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.
When sending a frame, Q.921 checks the number of unacknowledged frames. Suppose V(A) is the
sequence number of the previous acknowledged frame, V(S) is the sequence number of the frame to
be sent, and k is the sliding window size. If V(A) + k = V(S), the system stops sending frames.
Examples
# Set the sliding window size to 10 on ISDN PRI interface Serial 2/3/0:15.
<Sysname> system-view
[Sysname] controller e1 2/3/0
[Sysname-E1 2/3/0] using ce1
[Sysname-E1 2/3/0] pri-set
[Sysname-E1 2/3/0] quit
[Sysname] interface serial 2/3/0:15
[Sysname-Serial2/3/0:15] isdn pri-slipwnd-size 10
Related commands
isdn bri-slipwnd-size
isdn progress-indicator
Use
isdn progress-indicator
to set the progress description in the progress indicator information
element of ISDN signaling messages.
Use
undo isdn progress-indicator
to restore the default.
Syntax
isdn progress-indicator indicator
undo isdn progress-indicator