How Colt and Cisco are defining the future of Segment Routing

Colt was an early adopter of Segment Routing (SR) in 2017, working closely with Cisco to add value to its SR-based network. This early commitment has delivered key benefits, such as:

  • Greater network availability with 50ms protection mechanism, covering 100% of the possible network topologies using Topology-Independent Loop-Free Alternate (TI-LFA) SR
  • Higher network utilisation with simple and scalable MPLS segment routing traffic engineering for the data plane
  • Easier delivery of innovative network services
  • Reduced network complexity

Nearly four years since it was first deployed, Segment Routing is now deeply ingrained in Colt’s global network and is essential to delivering innovative services. This investment, and the benefits to customers, are why Colt and Cisco are playing an active role in the Internet Engineering Task Force (IETF) standardisation of Segment Routing technology.

Contributing to Segment Routing at the IETF

With a strong focus on operations, and more specifically on performance monitoring capabilities, Colt has been working with Cisco on two standardisation drafts that have been recently submitted to the IETF:

These define an operational framework, where one-way and round-trip performance metrics like delay, delay variation, and packet loss can be integrated into the path computation process for finding network paths that are compliant with the SLAs of the service.

“We have been working closely with lead operators to drive Segment Routing innovation since day one. I’m thrilled to see Colt join the fray, bringing their expertise through involvement in the standardisation process, adding incremental value to SR,” said Clarence Filsfils, Cisco Fellow.

“As a lead operator in adopting MPLS Segment Routing, we continue to be a proud contributor, partnering with Cisco to help develop capabilities on this technology for Colt’s Packet Network and the global network community,” said Bart Janssens, Senior Architect, Packet Network Engineering, Colt. “For Colt, this means we can create network slices using a custom set of SLAs, such as maximum delay or loss thresholds. This innovation will also drive differentiated 5G slicing and become an active part of our fault and performance monitoring platforms, making use of ML/AI for analysing and visualising future services.”

Segment Routing today in the Colt IQ Network

One of the service offerings enabled by Segment Routing that is getting strong traction with customers increases the network resiliency against any node, link, or even Shared Risk Link Group (SRLG) failures by guaranteeing two disjoint network paths between two customer locations. This new service is based on Cisco platforms – ASR 9000, NCS 5500, and NCS 540 – and takes advantage of the following capabilities:

At the forefront of service provider innovation, Colt is leading the way in deploying this solution and has a unique mastery of Segment Routing technology that the broader community can benefit from. Those interested in learning more about our work so far can find out more through a podcast with ACG Research or a presentation put together for APNIC.

Sharing expertise and building a partnership

Over the years, Colt and Cisco have built a rich and extended relationship that goes above and beyond sourcing; together we have engaged in a broad partnership and the work around Segment Routing has been particularly successful.

The journey doesn’t stop here. Colt is already working with the Cisco Segment Routing team to develop new cutting-edge solutions combining both Segment Routing and EVPN.

“It’s phenomenal to see how Colt has quickly rolled out Segment Routing at a global scale, delivering new and innovative services to its customer base,” said Kevin Wollenweber, Vice President of Networking, Mass-Scale Infrastructure Group, Cisco. “This long-lasting partnership exemplifies how we can jointly drive innovation in the market and create services that align to customer needs.”

“Our work with Segment Routing is a perfect example of Colt’s strategy and differentiators,” said Vivek Gaur, VP Engineering, Colt. “We’re delivering innovation in our network that will significantly benefit our customers, and we’re partnering with industry-leading companies, like Cisco, to drive the industry as a whole. I’m really proud of the work we’ve done so far and excited about what’s still to come.”


Vivek Gaur, Vice President of Network Engineering, Colt Technology Services

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