What is Traffic Steering?

Traffic steering is the SD-WAN capability that directs application traffic across available WAN paths – or to local internet breakout – based on match criteria, circuit and path priority, and SLA compliance, implemented through forwarding profiles bound to traffic-steering policies so each flow rides the path suited to it.

Key takeaways

• Traffic steering picks a WAN path per flow, not per physical link.
• Forwarding profiles rank circuits and next hops by priority and SLA.
• Policy rules match traffic by application, address, protocol, or DSCP.
• A path that violates its SLA is dropped for the next compliant one.
• Layer 2, Layer 3, and internet traffic steering cover different scopes.

On this page: Why it matters · How it works · Types · Traffic Steering & Versa · FAQ

Why is traffic steering important?

A branch with two or more WAN links – broadband, MPLS, LTE – must decide, for every flow, which link carries it and what happens when it degrades. A static routing table cannot answer either question; it picks one path and ignores whether that path still meets the application’s needs. Traffic steering answers both continuously, with no one watching a dashboard.

The payoff is application experience and cost control together. A voice call can ride the lowest-latency circuit while a bulk backup rides the cheapest one, and both decisions can change automatically once measured latency, jitter, or loss crosses a threshold. Without it, WAN link decisions are manual or accidental; with it, path selection is policy that reacts to real conditions rather than a fixed configuration.

What is traffic steering?

Traffic steering matches a session to a WAN path in two stages. A policy rule first identifies the traffic – by application, address, hostname, protocol, URL category, or DSCP – and points it at a forwarding profile. The profile then ranks circuits or next hops by priority; if an SLA profile is attached, only paths meeting the configured latency, jitter, and loss thresholds are eligible at that level. Ties between equally-ranked, compliant paths are resolved by weighted round-robin or a similar load-balancing method.

A circuit is a local WAN endpoint, such as WAN1 or LTE1; a path is the end-to-end route formed by pairing a local circuit with a remote one. The forwarding decision is made once per session and holds for its lifetime, unless continuous evaluation is enabled to move real-time flows off a path that falls out of compliance.

Types of traffic steering

Layer 2 SD-WAN traffic steering (Release 21.2.1 and later) steers bridged traffic between sites at the switching layer, using the same forwarding-profile and SLA-profile model as Layer 3. Layer 3 SD-WAN traffic steering is the routed equivalent, and also supports path eligibility from route lookups (equal-cost multipath) or an explicit next-hop list. Internet traffic steering, available on spoke devices, prioritizes local WAN circuits for internet- and SaaS-bound traffic so it breaks out directly at the branch instead of backhauling to a hub – local breakout as a traffic-steering policy. Web proxy traffic steering redirects specific traffic to a proxy server at a data center or hub instead of sending it direct.

Each type shares the same components – match criteria, a forwarding profile, an optional SLA profile – applied at a different scope.

Traffic Steering & Versa

On VOS devices managed through Director, traffic steering is configured as forwarding profiles: circuit and next-hop priority (up to 15 levels, plus Avoid and Last Resort), an SLA profile, a connection selection method such as weighted round-robin, symmetric forwarding, and advanced behaviors like forward error correction and packet replication that apply even to encrypted traffic. SLA smoothing, violation damping, and gradual migration stop flows from oscillating between compliant and non-compliant paths.

In Concerto’s newer workflow, the same policy is built from traffic-steering rules bound to a forwarding profile and, optionally, a TCP optimization profile, with four presets – Real Time, Business Critical, Default, Low Priority. SASE gateway deployments extend the same rules to zones like Host, Remote Client, SD-WAN, Trust, and Untrust. See Configure SD-WAN Traffic Steering for the Director procedure, its Concerto 13.1.1+ counterpart, and Configure Traffic Steering for the Titan portal.

Frequently asked questions

What is the difference between traffic steering and a path?

A path is one candidate route between two branches, formed by pairing a local WAN circuit with a remote one. Traffic steering is the decision process – policy rules plus a forwarding profile – that chooses which available path a flow uses, and re-evaluates that choice as conditions change.

How does traffic steering decide which WAN link to use?

A policy rule matches traffic by criteria like application or address and points it to a forwarding profile, which ranks eligible circuits or next hops by priority. If an SLA profile is attached, only paths meeting its latency, jitter, and loss thresholds qualify at each level.

What happens when a path fails to meet its SLA?

The path is demoted to an SLA-violated state, and the forwarding profile looks for another path at the next priority level that complies. The default action forwards traffic anyway if nothing compliant is found; it can instead be set to drop.

Does traffic steering work on encrypted traffic?

Yes. Advanced traffic-steering features – forward error correction, packet replication, per-packet load balancing – apply to all customer traffic regardless of encryption, including HTTPS, TLS, and IPsec-protected flows, because steering operates on the session as a whole, not the packet payload.

Is internet traffic steering the same as local breakout?

They describe the same outcome from different angles. Internet traffic steering is the policy mechanism – prioritizing local WAN circuits for internet-bound flows on a spoke device – that implements local breakout, so trusted traffic reaches the internet directly instead of routing through a hub.

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