3Com S7906E - Switch, Configuration Manual

Page: 294 / 2621

2-4
To do... Use the command... Remarks
Configure the related
parameters of ONU discovery
dba-parameters
{
discovery-frequency value
|
discovery-length value
|
cycle-length value
} *
Optional
By default, the
discovery-frequency
value
is 50, the
discovery-length
value is 41500 TQ, and the
cycle-length
value is 65535
TQ.
Return to system view
quit
—
Enter ONU port view
interface onu interface-number
—
Set the ONU's uplink bandwidth
limits and the delay mode of
packet forwarding.
upstream-sla
{
minimum-bandwidth value1
|
maximum-bandwidth value2
|
delay
{
low
|
high
} } *
Required
By default, the minimum
bandwidth of an ONU
is 2048
kbps, the maximum
bandwidth is 23552 kbps, and
low delay is adopted.
Configure the
number of queue
sets supported by
ONU Report
frames
dba-report queue-set-number
queue-set-number
Configure
the
administrati
on
attributes of
DBA
negotiation
Configure the
threshold for a
queue
dba-report queue-id queue-id
{
active
|
inactive
}
threshold
threshold-value
Optional
By default, ONU Report
messages support two queue
sets. The default thresholds
of queue 4 and queue 5 are
65535, while the default
thresholds of other queues
are 0.
1 time quantum (TQ) is equal to 16 ns, which is the time it takes to transmit two bytes of data at 1
Gbps.
You can manually load an external DBA algorithm file by using the
dba-algorithm update
command as needed.
DBA-related configuration is only recommended for administrators. Improper DBA configuration
may terminate all the services.
H3C ONU Report frames support up to two queue sets.
The sum of the minimum uplink bandwidths configured for all created ONU ports under an OLT port
cannot exceeds 921600 kbps, namely, 900 Mbps.
Configuring Grant filtering on the OLT port
In an EPON system, uplink transmission adopts the TDMA technology. An OLT assigns each ONU a
time slot and each ONU can only send data in its own time slot in sequence. Therefore, the OLT
implements strict time synchronization. Within the specified time, the OLT can only receive the packets
from the specified ONU. If the time synchronization of an ONU is inaccurate, however, the packets that
the OLT receives within a specified time period may be from another ONU. In that case, if grant filtering
is enabled on the OLT port, the OLT does not allow the received packets to pass through.
Follow these steps to configure other OLT functions: