Variable Bit Rate Dual-Leaky Bucket Policing Examples; Table 21-12 Policing Options For Vbr Connections - Cisco BPX-BXM-155-8DX Installation And Configuration Manual

Chapter 21 Configuring ATM Connections

Variable Bit Rate Dual-Leaky Bucket Policing Examples

The contract for a variable bit rate (VBR) connection is set up based on an agreed upon sustained cell
rate (SCR) with allowance for occasional data bursts at a Peak Cell Rate (PCR) as specified by
maximum burst size MBS.
When a connection is added, a VPI.VCI address is assigned, and UPC parameters are configured for the
connection. For each cell in an ATM stream, the VPI.VCI addresses are verified and each cell is checked
for compliance with the UPC parameters as shown in Figure 21-23.
The VBR cells are not enqueued, but are processed by the policing function and then sent to the network
unless discarded.
For VBR, traffic policing, depending on selected policing option, is based on:
•
•
The policing options for VBR connections, selected by entering 1-5 in response to the policing choice
prompt, are shown in Table 21-12:

Table 21-12 Policing Options for VBR Connections

VBR.1
VBR with
policing set to 1.
VBR.2
VBR with
policing set to 2.
VBR.3
VBR with
policing set to 3.
VBR with
policing set to 4.
VBR with
policing set to 5.
Release 9.3.0, Part Number 78-10674-01 Rev. D0, July 2001
Leaky bucket 1, PCR and CDVT
Leaky bucket 2, SCR, CDVT, and MBS
CLP(0+1) cells compliant with leaky bucket 1 are passed to leaky bucket 2;
non-compliant cells are discarded. CLP(0+1) cells compliant with leaky bucket
2 are admitted to the network; non-compliant cells are discarded.
CLP(1) cells compliant with leaky bucket 1 are admitted to the network;
non-compliant CLP(0+1) cells are dropped. CLP(0) cells compliant with leaky
bucket 1 are applied to leaky bucket 2; non-compliant cells are dropped. CLP(0)
cells compliant with leaky bucket 2 are admitted to the network; non-compliant
cells are dropped.
CLP(1) cells compliant with leaky bucket 1 are admitted to the network;
non-compliant CLP(0+1) cells are dropped. CLP(0) cells compliant with leaky
bucket 1 are applied to leaky bucket 2; non-compliant cells are dropped. CLP(0)
cells compliant with leaky bucket 2 are admitted to the network; non-compliant
cells are tagged and admitted to the network.
CLP(0+1) cells compliant with leaky bucket 1 are admitted to the network;
non-compliant cells are dropped. Leaky bucket 2 is not active.
Policing is off, so there is no policing of cells on ingress.
Cisco BPX 8600 Series Installation and Configuration
Traffic Policing Examples
21-47