Cisco Crosswork Network Controller 7.2.x Network Bandwidth Management

PDF

Cisco Crosswork Network Controller 7.2.x Network Bandwidth Management

Configure bandwidth on demand

Updated: January 30, 2026

Want to summarize with AI?

Log in

Use this procedure to enable BWoD and create BWoD SR policies to dynamically manage network bandwidth.

Before you begin

Both CSM and BWoD cannot be enabled at the same time. If you have CSM enabled, you must disable it before enabling BWoD.

Note

It is recommended to delete the respective policies from the network before disabling the associated function pack (BWoD or CSM). If policies remain in the disabled function pack, this may cause issues with new policy delegation and increase processing time.

Complete these steps to configure bandwidth on demand and create BWoD SR policies. As long as BWoD is enabled, you can create multiple BWoD SR policies.

Procedure

1.

From the main menu, choose Services & Traffic Engineering > Bandwidth on Demand > Configuration.

2.

Toggle the Enable switch to True.
3.

Configure the required options. Refer to the BWoD configuration options section to view the description of each field.
4.

Click Commit changes to save the configuration.

5.

To create BWoD SR policies, choose Services & Traffic Engineering > Traffic Engineering > SR-MPLS tab and click Create > PCE init.
6.

In addition to entering the required SR policy details, click the Bandwidth on demand option and enter the required bandwidth.
7.

If applicable, enter a Flexible Algorithm constraint in the SID Algorithm field. The values correspond to the Flexible Algorithm that are defined on the device and the 128-255 range is enforced by Cisco IOS XR. Crosswork Network Controller will try to find a path with this SID. If a path with the SID constraint cannot be found, the provisioned policy will remain operationally down until the conditions are met.

8.

Click Preview to view the proposed SR policy.

9.

Click Provision to commit the SR policy.

BWoD configuration options

These tables provide information on the BWoD configuration options available in the UI.

Basic BWoD options

Table 1. Basic configuration options

Option

Description

Enable

Enables or disables the BWoD function pack.

Primary Objective

Sets the primary objective when optimizing policies.

  • Maximize available bandwidth: Computes an SR policy path maximizing the overall available bandwidth in the network. This setting generally attempts to maximize usable network capacity at the expense of potentially longer paths.

  • Metric minimization: Computes an SR policy path minimizing the metric selected. This setting generally results in the shortest available paths for a metric type.

Link Utilization

Sets the congestion constraint (in percentage). When searching for paths for delegated policies, the Bandwidth on Demand will avoid any path that may exceed this utilization threshold, ensuring traffic is not routed through congested links. Additionally, when an interface exceeds this value, the system will trigger optimization to redistribute traffic and alleviate congestion.

Re-optimization interval (seconds)

Sets the minimum time (in seconds) before paths can be re-optimized if network conditions change. This acts as a countdown timer; the BWod policy will wait for this duration to expire before allowing re-optimization.

Metric re-optimization time

Sets the duration (in seconds) before paths can be re-optimized for metric improvements. If bandwidth requirements are met but a better IGP or TE path is available, BWod will wait for this timer to expire before re-optimizing. This helps prevent frequent path changes and unnecessary re-optimizations.

Advanced BWoD options

Table 2. Advanced configuration options

Option

Description

SR policy traffic

Determines how bandwidth optimization is calculated for each policy.

  • Measured: Uses the current measured traffic of BWoD provisioned SR policies for optimization caculations.

  • Max measured requested: Uses the maximum value between the current measured traffic on BWoD provisioned SR policies or the amount of bandwidth requested for optimization calculations.

Update throttle (seconds)

Sets the time (in seconds) to wait between updates. Set to 0 to disable throttling.

Optimizer event threshold (seconds)

Sends an alert to the UI if the optimizer runs longer than the specified time (in seconds).

Note

In large-scale environments, the optimizer run may exceed the default run time limit of 60 seconds. For deployments where policies are provisioned in batches of 100, setting the Optimizer event threshold to 240 seconds and the Optimizer run time limit to 300 seconds has been effective in internal testing. For environments where 1,000 or more policies are deployed, these values may need to be increased further. Adjust these parameters based on the scale of your deployment to ensure optimal performance.

Optimizer run time limit (seconds)

Sets the maximum allowed run time (in seconds) for the BWoD optimizer.

Note

In large-scale environments, the optimizer run may exceed the default run time limit of 60 seconds. For deployments where policies are provisioned in batches of 100, setting the Optimizer event threshold to 240 seconds and the Optimizer run time limit to 300 seconds has been effective in internal testing. For environments where 1,000 or more policies are deployed, these values may need to be increased further. Adjust these parameters based on the scale of your deployment to ensure optimal performance.

Policy violations

Determines how BWoD responds when new policies are provisioned and policy violations are detected.

Prefer strict SIDs

When enabled, prefers strict SIDs when deriving segment lists. Required for compatibility with LCM.

Debug optimizer

Enables logging of optimizer plan files to the Crosswork Network Controller file system. The number of saved files is limited by the Debug opt max plan files setting.