H3C Technologies H3C S7500E Series Switches - Manual (Page 33)

4-2
When you remotely manage ONUs on an OLT device, extended OAM can encapsulate various
operation and acknowledgement information in the Data field. The data field consists of the following
sub-fields:
z OUI: The OUI address of the transmitting device.
z Ext.Opcode: Extended operation code. Extended OAM uses different codes for identifying the
operation types of OAMPDUs, as described in Table 4-1 .
Table 4-1 Description on the extended operation codes
Code Operation type Description
0x01 Extended Variable Request
Sent from an OLT to an ONU, carrying
the user's query instructions.
0x02 Extended Variable Response
Sent from the ONU to the OLT in
response to a query request, carrying the
requested information.
0x03 Set Request
Sent from the OLT to the ONU, carrying
the user's configuration instructions for
the ONU.
0x04 Set Response
Sent from the ONU to the OLT after the
ONU finishes the configuration instructed
by the user.
0x0A
DBA (Dynamic Bandwidth
Allocation)
Used for performing DBA configuration
and query.
z Payload: Carries the function codes and configuration contents corresponding to the user’s query
or configuration instructions. An OLT can configure the functions shown in Extended OAM
management for ONUs.
z Pad: Padding field.
How Extended OAM Works
Extended OAM has two functions: extended OAM discovery and extended OAM management.
Extended OAM discovery
An OLT and an ONU perform extended OAM discovery to determine whether they can communicate
properly before transmitting data.
First, the OLT and the ONU use standard OAM to judge whether the link in between is normal. If the
link is normal, the OLT and the ONU exchanges Extended Information OAMPDUs to inform each other
of their OUI addresses, supported OUI addresses, and OAM version numbers. If the OUI address and
OAM version of each end can be supported by the other end, the extended OAM discovery process
finishes and data transmission starts. Otherwise, the two ends cannot communicate normally.
Extended OAM management
After finishing extended OAM discovery, the OLT device can remotely configure the ONU by sending
Organization Specific OAMPDUs.