# Why Traffic Steering is a Moot Point in Packet-Based Bonded SD-WAN Scenarios In the realm of Software-Defined Wide Area Networking (SD-WAN), much of the early excitement centred on traffic steering—the ability to dynamically direct application flows across multiple WAN paths based on real-time link performance, application type, or business policy. While powerful in concept, traffic steering is no longer a pressing concern in modern SD-WAN architectures that leverage **packet-based bonding**. In such implementations, the very premise of steering traffic across individual paths becomes irrelevant. This article explores why **traffic steering is a moot point in bonded packet-based SD-WAN**, how packet-based and session-based load balancing differ, and why modern implementations, such as Fusion’s SD-WAN, achieve superior results without relying on the legacy concept of traffic steering. ### Session-Based vs. Packet-Based Load Balancing in SD-WAN ![](https://cdn.hashnode.com/res/hashnode/image/upload/v1753088153444/afcb3e38-e702-40db-a237-e3fc341f9147.png align="center") #### **Session-Based Load Balancing** In traditional SD-WAN implementations—especially those using session-based architectures—each network session (typically defined as a five-tuple of source IP, destination IP, source port, destination port, and protocol) is mapped to a specific WAN link at the session’s start. Once assigned, all packets belonging to that session flow across the chosen link until the session terminates. This approach allows the SD-WAN to maintain session integrity without the need for sophisticated reordering mechanisms. However, it comes with limitations: * **Underutilisation of links**: If one link is congested and another is idle, active sessions cannot shift mid-flow. * **Delayed response to performance degradation**: Re-steering a session requires detection, closure, and re-establishment, which is reactive. * **Dependent on traffic steering logic**: Optimal performance is reliant on accurate and responsive traffic steering algorithms. #### **Packet-Based Load Balancing** Packet-based bonding takes a more advanced approach. Instead of sending entire sessions down one path, **individual packets from the same session are distributed across multiple WAN links** simultaneously. This allows full bandwidth utilisation and real-time failover, as traffic flows can dynamically adapt at the packet level. Key advantages include: * **Maximum bandwidth utilisation**: All available links are used in parallel, regardless of session. * **Real-time failover**: If a link fails mid-session, only a few packets are lost. The session continues seamlessly over the remaining paths. * **Dynamic compensation for link quality**: Algorithms can favour higher-quality links on a per-packet basis, adjusting instantly to jitter, packet loss, or latency. --- ### Why Traffic Steering Becomes Irrelevant In a bonded, packet-based architecture, traffic steering no longer applies in the traditional sense. Here’s why: #### 1\. **All Links Are Active for All Traffic** Traffic isn’t “steered” to a specific path based on performance—it’s dynamically split **per packet** across all links. This means there's no need to “decide” which path is best for a particular session or application. The bonded tunnel continuously evaluates each link’s performance in real time and assigns each packet to the optimal path at that moment. #### 2\. **Session-Aware Traffic Steering Isn’t Needed** Because packets can be reassembled in-order by the receiving SD-WAN node, the concept of assigning sessions to a single WAN path for consistency becomes obsolete. Packet ordering and flow integrity are preserved by the overlay layer, freeing the system from session stickiness requirements. #### 3\. **Failure Handling Is Instantaneous** With packet-based bonding, failure detection and failover do not require session termination or reassignment. Since every packet is evaluated independently, traffic can bypass faulty links without human intervention or complex re-routing logic. #### 4\. **Redundancy and Speed Outperform Manual Optimisation** Traffic steering assumes a network operator must configure or automate policy-based routing to improve performance. In bonded packet-based systems, there’s **nothing to configure**. The optimisation is automatic, granular, and reactive at microsecond-level resolution. --- ### Nepean Network’s SD-WAN: A Case Study in Bonded Resilience Nepean Network’s SD-WAN platform exemplifies the power of bonded packet-based routing. Its platform creates a virtualised tunnel that spans up to three separate WAN circuits. Whether combining fibre, fixed wireless, or LTE, Nepean Network’s SD-WAN: * Sends **split packets across all active links**. * Monitors link health at **sub-second intervals**. * Reacts in real time to **latency, jitter, or packet loss**. * Delivers **single IP continuity**, masking link disruptions. * Eliminates the need for **manual steering policies**. The result is **no downtime, no decisions, and no steering**. Whether you're running VoIP, cloud applications, or real-time industrial telemetry, all flows are bonded across every path with optimal use of available bandwidth. --- ### Wrap Traffic steering, once a core feature of SD-WAN, is rendered obsolete by packet-based bonding. When every packet can be optimally routed in real time, the notion of “steering” entire sessions to specific links becomes not just unnecessary but counterproductive. Bonded packet-based SD-WAN solutions like Nepean Network’s offer superior performance, resilience, and simplicity. In these environments, **steering is not only moot—it’s a relic of an older network philosophy**. The future lies in intelligent, real-time, per-packet optimisation, not reactive per-session redirection. --- %[https://bsky.app/profile/mastelek.bsky.social/post/3luhmuirdcc2i]