Foresight Congestion Control; Atm Connection Requirements; Figure 21-2 Abr Vsvd Flow Control Diagram; Table - Cisco BPX-BXM-155-8DX Installation And Configuration Manual

ATM Connection Requirements

Figure 21-2 ABR VSVD Flow Control Diagram

Forward flow data cells
Source
Only the flows for forward data cells and their associated RM cell
control loop are shown in this diagram. The flows for backward
flow data cells (destination to source) and their associated RM
cell control loop are just the opposite of that shown for the forward
flow data cells.
NE = Network element

ForeSight Congestion Control

The ForeSight feature is a proprietary dynamic closed-loop, rate-based, congestion management feature
that yields bandwidth savings compared to non-ForeSight equipped trunks when transmitting bursty
data across cell-based networks.
ForeSight may be used for congestion control across BPX/IGX switches for connections that have one
or both end points terminating on BXM cards. The BXM cards also support the VSVD congestion
control mechanism as specified in the ATM Traffic Management 4.0 standards.
ATM Connection Requirements
Two connection addressing modes are supported:
•
•
The full ATM address range for VPI and VCI is supported.Virtual Path Connections are identified by
an * in the VCI field. Virtual Circuit Connections specify both the VPI and VCI fields.
The VPI and VCI fields have significance only to the local BPX switch, and are translated by tables in
the BPX switch to route the connection. Connections are automatically routed by the AutoRoute feature
once the connection endpoints are specified.
Cisco BPX 8600 Series Installation and Configuration
21-6
Node Node
NE NE
Forward RM cells
RM cell control loop for forward flow data
Backward RM cells
You may enter a unique VPI/VCI address in which case the BPX switch functions as a virtual
circuit switch.
You may enter only a VPI address in which case all circuits are switched to the same destination
port and the BPX switch functions as a virtual path switch in this case.
Node
Destination
NE
Release 9.3.0, Part Number 78-10674-01 Rev. D0, July 2001
Chapter 21 Configuring ATM Connections