Strategy
A Strategy (formerly Link Sharing Policies) defines how the Router uses the available WAN links for a specific class of traffic on an Overlay.
These WAN links are identified through WAN labels. The policy is applied in the context of a Traffic Rule attached to an Overlay, which means it controls the WAN behavior for that traffic class only.
Strategy (formerly Link Sharing Policies) can use either legacy behavior or probe-based behavior.
Performance-Based Policies
Newer policies use a probe that continuously measures the quality of each WAN link. The probe can evaluate metrics such as delay, jitter, packet loss, and reachability, depending on the implementation.
Policy | Behavior |
|---|---|
Primary/Backup | Uses the primary WAN link first. If the primary link is unavailable, traffic is moved to the backup link. |
Load Balance | Shares traffic across multiple WAN links based on the configured load-sharing behavior. |
This allows traffic steering to follow the current quality of the underlay network instead of relying only on static configuration or manual checks.
Legacy Policies
Legacy policies use the configured WAN order and traditional availability or load-sharing methods.
Policy | Behavior |
|---|---|
Fastest | Selects the WAN link with the best composite score. A hysteresis mechanism, typically around 20%, helps avoid frequent switching between links. |
Performance | Load balances traffic across WAN links that meet the selected Performance Objective. The objective can include delay, jitter, packet loss, or a combination of these metrics. This policy uses primary and secondary WAN roles, with product-defined fallback behavior when no link meets the objective. |
Available | Load balances traffic across WAN links that are reachable. Links with complete packet loss are excluded. |
These policies do not use the newer continuous quality probe model. They rely mainly on configured link order, availability, and classic load-sharing logic.
Role in the Model
The Strategy (formerly Link Sharing Policies) determines how traffic uses WAN links after it has matched a Traffic Rule and selected an Overlay.
For example, real-time traffic can use a Performance policy to avoid links with high delay or jitter, while guest internet traffic can use an Available policy to use any reachable WAN link.
In this way, the Strategy (formerly Link Sharing Policies) connects traffic classification to real-time WAN path selection.