B&B Electronics 856-14205--29 - Manual - Manual (Page 31)

Configuration
26
be sent. If the internal buffers are full, excess
traffic will be dropped. The Unit Rate Control can
be used to alleviate this.
DATA PORT
Ingress Bandwidth
Limit
(CIR)
Monitors the traffic entering the unit (ingress),
discarding traffic that exceeds a fixed Committed
Information Rate (CIR) plus Burst Allocation (BA).
Frames are not held in queue, they either meet the
bandwidth limits and are accepted into the unit or
they are dropped.
Max Burst Allocation
size (BA) The BA size is specified in bits; the # of bits above
the bandwidth limit before packets are thrown away.
Ingress Burst
Allocation Bandwidth limiting can be set at Ingress of each port
individually by setting the MAX BW Limit in bits/sec.
and the BA in bits. Traffic in excess of the bandwidth
limit plus BA for any time interval will be dropped.
This function utilizes an advanced “Leaky Token-
Bucket” algorithm to provide typical resolution under
5% of the set values at all data rate and frames sizes.
Egress Traffic
Shaping Actively controls the transmitter and hard limits the
maximum frame rate that can be sent. Frames can
be delayed in the internal buffers of the unit, waiting
their turn to be sent. If the internal buffers are full,
excess traffic will be dropped. The Unit Rate Control
can be used to alleviate this.
OSI Level Used in
Calculations
(Open Systems
Interconnect, referring
to the seven layers for
TCP/IP)
Choose Layer 1, 2 or 3 for the counter, this will
determine how many bytes from the Ethernet frame
are to be included in the calculations.
Layer 1:
Layer 2:
Layer 3:
Preamble + DA to CRC + IFG
Frames DA to CRC
Frames DA to CRC – 18
(- 4 if frame is tagged)