H3C Technologies H3C S7500E Series Switches - Manual (Page 59)

4-6
To do… Use the command… Remarks
Set the ONU's uplink bandwidth
range 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 used.
The configuration of the downlink bandwidth limit takes effect only when the downlink bandwidth
allocation policy is enabled.
The configured downlink bandwidth limit takes effect only on known unicasts, but not on unknown
unicasts, multicasts, or broadcasts.
The sum of the minimum uplink bandwidths configured for all the existing ONU ports under an
OLT port cannot exceed 921600 kbps, namely, 900 Mbps.
Enabling Related Protocols on an ONU
You can use an OLT to remotely enable RSTP, DHCP snooping, DHCP snooping Option82, and
PPPoE+ on an ONU through extended OAM packets.
RSTP
Enabling RSTP on an ONU can eliminate the loops between the UNIs or in the user networks by
blocking redundant links.
DHCP Snooping
After DHCP snooping is enabled on an ONU, a DHCP snooping table will be generated on the ONU to
record the IP address and user MAC address information that the DHCP client obtains from the DHCP
server, with each record being an entry in the DHCP snooping table.
DHCP Snooping Option82
With DHCP snooping Option82 enabled on an ONU,
For DHCP request messages with Option82 fields, the ONU replaces the Option82 fields with the
local one before broadcasting the DHCP request messages;
For DHCP request messages without Option82 fields, the ONU adds the Option82 field (which
contains ONU MAC addresses, number of the UNI connected to the DHCP client, and the VLAN
to which the UNI belongs) into the request messages when the DHCP client connected to the
ONU sends DHCP request messages to the DHCP server. This allows the DHCP client addresses
to be recorded in the DHCP server.
PPPoE+
The Point-to-Point Protocol over Ethernet (PPPoE) technology interconnects large numbers of hosts
through Ethernet, allowing the hosts to access the Internet through a far-end access device, and
implementing control and accounting functions on each connected host. Operating in the client/server