Virgin Media


Virgin Media operates multiple national SDH transport networks. Their network growth has been both planned and through acquisition. With consolidation and integration of these networks Virgin Media experienced challenges including sporadic pointer adjustment events and equipment holdover alarms. These occurred especially during routine maintenance and during minor transmission failures. These events were recognised to be synchronisation related and a cause for concern.


Horsebridge were called in to audit the network synchronisation configuration. Using Sync Architect we modeled the entire transport network using configuration information from the element management systems.

On simulation it became apparent that there were discrepancies between the actual network traffic element synchronisation configurations and the synchronisation network plan.

In particular incorrect configuration of Synchronisation Status Messaging (SSM) functionality prevented automatic synchronisation ring recovery during routine maintenance and trail loss.


  • Horsebridge presented the audit identifying systematic errors in existing network configuration and necessary process for rectification.
  • Virgin Media purchased Sync Architect and used it to identify and correct network equipment configuration faults.
  • Virgin Medias’ network no longer suffers from day-to-day synchronisation anomalies.
  • Reductions in deployment of synchronisation equipment have resulted in a reduction in both OPEX and CAPEX expenditure.
  • Sync Architect is now used in-house to maintain network equipment configuration settings, synchronisation port assignments and also to perform risk analysis on scheduled maintenance activities.