Segment routing

SDN starts with application-driven network routing

What if your applications could communicate their requirements, such as jitter, bandwidth, and latency, to the network? What if your network would have the ability and agility to respond to the application’s reported needs?


In terms of efficiency, network traffic and road traffic aren’t that different. Going from one side of town to the other, the shortest path, right through the middle, isn’t always the best path. We’ve all had our moments when we got stuck in traffic following the recommended “shortest path”, instead of saving time by going around it. These days, modern GPS services have adapted by using client feedback to calculate the fastest (even if longer) route, and service provider networks are providing similar improvements with segment routing.

Operators have long optimized MPLS traffic to avoid congestion, meet SLAs, and even avoid certain countries due to legal requirements. Segment routing is the software upgrade designed to give service providers more control over their network. Instead of only attaching the final destination to each packet, this new approach to routing means that each packet carries the information defining each step it needs to take to the destination. Most importantly, the priorities of the application define what this best path is.

Not all network traffic is equal

The VOIP application might request a low-jitter path because any delay or distorsion harms user experience.

A different application might request a low-cost path to transfer large quantities of bulk data.

Financial transactions and video streaming have vastly different priorities, and segment routing allows the applications themselves to communicate these priorities to the network.

Rather than manually configuring and managing each tunnel, sometimes tens of thousands of them, segment routing offloads the route management to a routing controller. The controller equips the traffic itself with the map on how to get where it needs to go, in a way that is understood by all industry leading network controllers.

When will you need to look into segment routing?

Putting aside the fact that you’re looking into it right now, segment routing most visibly impacts application value and deployment. At the end of the day, application provision is what drives customer value, and segment routing gives you the flexibility networks need to answer application needs.

Additionally, it changes how we approach and manage tunneling, by removing the need for thousands of individually configured MPLS tunnels. This offers new applications a significantly reduced time-to-market, lower cost of deployment, and best of all, it doesn’t require any hardware changes to the existing MPLS network.

Multi-vendor support: The standardization process is undergoing at IETF and is supported by network industry leaders.

Where do we go from here

The first step in any MPLS network looking to implement segment routing is ensuring that the existing infrastructure is ready for it.

  • Survey: The network needs to be surveyed to identify any needed node software upgrades and catalogue existing tunnels in place.
  • Design: Once readiness is ensured, you’ll probably move on to design, training, deployment, and after it’s all done, support.
  • Consulting: We can help you in any stage of the design and deployment of Segment Routing in your environment.
  • Training: NIL delivers authorized courses that will teach your team how to leverage the power of Segment Routing for your business.
  • Support: We can also provide support to your teams designing, implementing and operating applications making use of Segment Routing in your environment.