| Description | This table defines the control and status indication
objects for the optical interface of the EPON interface.
Each object has a row for every virtual link denoted by
the corresponding ifIndex.
The LLID field, as defined in the [802.3ah], is a 2-byte
register (15-bit field and a broadcast bit) limiting the
number of virtual links to 32768. Typically the number
of expected virtual links in a PON is like the number of
ONUs, which is 32-64, plus an additional entry for
broadcast LLID (with a value of 0xffff).
Although the optical interface is a physical interface,
there is a row in the table for each virtual interface.
The reason for having a separate row for each virtual
link is that the OLT has a separate link for each one of
the ONUs. For instance, ONUs could be in different
distances with different link budgets and different
receive powers, therefore having different power alarms.
It is quite similar to a case of different physical
interfaces. |