Cisco ACI Case Study. When this leading UK water utility customers’ turn on a tap, they expect a consistently good experience. And that’s exactly the kind of expectation this utility had for its network. They needed a platform that could efficiently handle the day-to-day but scale to meet demand. One that could do more, with the same headcount. And most importantly, one that could keep their 3.5m customer records safe.

Their IT team were already seeing a cloud-first strategy pay off with greater flexibility, security and efficiency. Now, they wanted the same for the on premises network. And with their existing “monolithic” network having seen 10 years of service, they knew it was time to invest in the future.

OCSL’s experts pinpointed a Cisco ACI (Application Centric Infrastructure) as the ideal solution. It would streamline the management of virtual & physical environments, transform performance, standardise deployment and automate day-to-day IT tasks. With this powerful new automated Software Defined Network in place, IT service levels have been dramatically improved.

A fresh perspective

Compared to the existing network the new ACI “spine and leaf” topology offered greater security, flexibility and visibility.  Using Gartner-recommended Fixed Form Factor (FFF) hardware building blocks and software, it offers the ultimate in network flexibility. To minimise any issues, our experts proposed a bite-sized approach to migration.  And working closely with the internal IT team, we made sure knowledge was fully transferred. As a further step, we designed a robust test to ensure no one could touch the network without the right skills. And as a final level of our reassurance, our 24x7 Cisco total support package gives complete confidence in their systems to help deliver over 900 million litres of water to customers each day.

A better answer

“The Cisco ACI has revolutionised our approach to networking. We can now split business streams into various units, provide common shared services -  for example, security, backup, internet and core business application - then control access to the relevant services” said their Network Manager. “Because of the segmented approach it’s much easier and faster to manage than previously.” Now, they can deploy “any workload, anywhere” across physical and virtual environments. All with the peace of mind that there’s consistent policy and security across the board. Maintaining network health is much easier too; the Cisco Application Policy Infrastructure Controller (APIC) automatically generates a Health Score. And integration with industry-leading orchestration, security, Layer 4 through 7 services, and management tools is much simpler. “I estimate that we’ve been able to do 50% more, with the same headcount.” continued their Network Manager, “This means we can roll out new systems and customer enhancements faster than ever before.”  Next steps for OCSL will be integrating existing Citrix and VMware vCenter technology. And for this utility company the “what if” questions about network stability are now a distant memory.


  • Faster deployment of apps
  • Increase in productivity
  • PCI compliance 


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What impressed us about OCSL was their ability to design and migrate the new ACI. No other supplier could offer both.

Water Utilities


Leading UK Utilities Organisation

Cisco ACI Case Study


  • Drive IT & operational efficiency 


  • Design, build & run an ACI network


  • Faster deployment of apps
  • Increase in productivity
  • PCI compliance targets met

Technology & Solution overview

Core Switch Replacement

  • x 2 Cisco Nexus 3048TP switches

ACI Switches

  • Spine: Cisco Nexus 9336
  • Leaf: Cisco Nexus 93180YC & 93108TC

Cisco Application Policy Infrastructure Controller (APIC) with API web interface

  • Open Architecture for 3rd Party integration
  • Single security for physical & virtual environments


  • 3 Year 24x7x4 Cisco
  • SmartNet support with onsite engineer

Project methodology