7-34 Cisco BPX 8600 Series Reference
Traffic Policing Examples
Figure 7-20 shows a VBR.3 connection policing example, with policing set to 3, and Leaky bucket 2
shown as non-compliant. Leaky bucket 2 is shown policing the CLP(0) cell stream for conformance
with maximum burst size MBS (as specified by BT), and for compliance with SCR sustained cell
rate. For the policing = 3 selection, CLP tagging is enabled, so the cells that have exceeded the BT
+ CDVT(0+1) limit are tagged as CLP=1 cells and admitted to the network. In this example, either
the sustained cell rate could have been exceeded for an excessive interval, or a data burst could have
exceeded the maximum burst size allowed.
Figure 7-20 VBR.3 Connection, Policing = 3, with Bucket 2 non-compliant
CLP=1
5
CLP=0
4
CLP=1
3
CLP=0
2
CLP=0
1
+
PCR(0+1)
CDVT(0+1)
Time
interval
variations
Leaky Bkt 1
Connection setup
and compliance status:
VBR.3
Policing = 3
Bkt 1 depth < CDVT(0+1)
Bkt 2 depth > BT + CDVT
S6350
Leaky Bkt 1
discards
if depth >
CDVT(0+1)
+
SCR
BT + CDVT
Leaky Bkt 2
CLP=1
5
CLP=1
3
CLP=0
4
CLP=0
2
CLP=0
1
CLP=0
4
CLP=1
2
CLP=1
1
CLP(1) cells compliant with Leaky Bkt 1, admit to network
CLP(0) cells
compliant with
Leaky Bkt 1
are applied to
Leaky Bkt 2
Two CLP(0) cells, 1 and 2,
are shown as non-compliant
with the BT + CDVT limit of
Leaky Bkt 2. With policing = 3,
the cells are tagged as CLP=1
and admitted to the network.
