PLANET EPL-1000 - Manual (Page 40)

equivalent to restore factory default and “Create” is equivalent to change the SLA from
default value.
It is important to note that though the logical link panel appears grouped under the ONU,
logical link attributes are NOT necessarily attributes of the ONU itself. Logical links
ALWAYS make two associations one with the ONU and one with the OLT. Unless explicitly
specified, logical link parameters may be parameters of the OLT, ONU or both. It is best to
assume that ALL operations performed on a logical link involve OAM transactions with the
ONU.
Though the TK3721 has a Min/Max FIFO scheduler in the upstream direction, the DBA is
not directly influenced by the Min scheduler. Instead it responds to signals generated by
queue depth. To ensure that the Min’s are scheduled accurately it is necessary to restrict
the total upstream bandwidth of the PON by 50 to 100Mbps. This can be accomplished by
provisioning an aggregate SLA.
As per IEEE 802.3ah, any ONU admitted to the network will be granted a small amount of
bandwidth sufficient for minimal OAM operation, even if the SLA is disabled. A disabled
SLA can use up to 256K. As per specification the ONU is not aware of SLA’s, and thus will
continue to transmit user data which will be dropped by the OLT. To prevent the ONU from
transmitting this unwanted data it is recommended that the ONU be configured in strict boot
mode. In this mode the ONU will ONLY transmit user data after the host software has
explicitly enabled it to do so.
In strict (or host driven) boot mode the SLA will be configured in the disabled state every
time the link is registered. In auto-boot mode the state of the SLA is enabled by default and
stored in the OLT NVS if NVS is enabled.
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