3Com S7906E Command Reference Manual page 1682

Fast Ethernet port: 64 to 100000
GigabitEthernet port: 64 to 1000000
Ten-GigabitEthernet port: 64 to 10000000
Note that the committed-information-rate argument must be a multiple of 64.
cbs committed-burst-size: Specifies the committed burst size in bytes.
The committed-burst-size argument ranges from 4000 to 16000000.
If the cbs keyword is not used, the system uses the default committed burst size, that is, 62.5 ms x
committed-information-rate, or 16000000 if the multiplication is more than 16000000.
Description
Use the qos lr outbound command to limit the rate of outbound traffic via physical interfaces.
Use the undo qos lr outbound command to cancel the limit.
Examples
# Limit the outbound traffic rate on GigabitEthernet 2/0/1 within 640 kbps.
<Sysname> system-view
[Sysname] interface GigabitEthernet 2/0/1
[Sysname-GigabitEthernet2/0/1] qos lr outbound cir 640
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