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JLL: SIP Migration Reduces Risk, Boosts Performance, Cuts Costs

JLL (Jones Lang LaSalle) provides real estate and investment management services, including property leasing, management, and consulting, and operates in the commercial real estate industry.


Jones Lang LaSalle (JLL) is a business with a history of responding decisively to changing business conditions. Faced with the deadlines imposed by SIP, the JLL management team decided they could not delay further and commenced plans to withdraw ISDN services from more than 60 offices across the UK and Europe.

They are a world leader in real estate services, building and investing in a variety of assets including industrial, commercial, retail, residential and hotel real estate.

  • Revenues: $16.3 billion
  • Workforce: 82,000
  • Global offices: 300, across 80 countries
  • Property managed: 4.6 billion square feet
  • Leasing transactions: 33,700, totalling 784 million square feet


Businesses across the world are implementing SIP. For many, the move is an essential step towards deploying modern SIP-enabled cloud communications and saving costs.

Aside from the benefits, the move to SIP had taken on a more urgent, obligatory requirement when BT announced that it is phasing out ISDN, starting with a cease in supply from 2020 and migrating fully to SIP and IP infrastructure by 2025.

This lead to JLL looking for a solution provider they could trust and who would take them on the journey to upgrade their infrastructure, tailoring the replacement technology to their unique requirements.

Taking into account the scale of the project and the risks involved, JLL called on the experience of Kerv C&C to provide project planning consultancy, a scope of works and a requirements definition across business and technical operations. This initial ‘discovery’ phase of the project would serve as the basis for a tender to select a suitable service provider for implementation of the SIP installation work.


Kerv C&C consultants identified existing Avaya telephony infrastructure operating across a Verizon MPLS core network between data centres in Frankfurt and Slough. Ninety-five percent of calls were carried across ISDN connections. Having established that the core was SIP-ready, Kerv saw that deployment of SIP trunks across the existing core network would offer the simplest and most economical solution, bringing with it a transformation in security, quality of service and call expenditure.

Kerv C&C’s assessment of inventory, network capacity, costs and existing contractual commitments included detailed analytics and sometimes complex appraisal of technical issues. The results exposed potential annual savings in the order of six figures, presenting JLL management with a relatively simple decision to proceed with implementation.

Following a sequence of design, roll-out and hand-over, the project sought to mitigate risk whilst achieving maximum return on investment and optimal SIP performance.

The project was supported by a Kerv Collaborate team comprising past employees of tier-one network carriers and international telecommunications
providers. With this hands-on, ‘insider’ knowledge of systems and processes used by the industry, Kerv projects benefit from uniquely close
collaboration between the client and supply sides of the project, delivering rapid resolution of technical issues and acceleration of
completion times.

Managing Time and Costs

The combined savings from removing ISDN line costs and rerouting of calls across the new SIP-enabled infrastructure resulted in a remarkable saving of 47% across the total region, with reductions as high as 80% in some individual European countries. By benchmarking tariffs, cutting under-utilised services and negotiating new contracts, Kerv C&C has leveraged the reduction of existing costs and set out terms with carriers for continued savings in the future.

With projects of this type, it is common for technology to be the focus of attention. In reality, though, it is the administration and management of often complex peripheral issues that can incur the bulk of project time. These tasks rely on the experience of the project team to ensure success. Order management, for example, was a detailed and critical process often governing the cost and timescales incurred by the project, as well as the quality of the product specification.

Similarly, hiring and management of local service providers, putting the right resource in the right place at the right time, was essential to system performance and achievement of deadlines.

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