Colt + Quendra help SD Worx to replace WAN connectivity, ISDN + SIP trunking services
Delivering services procured on a per-country basis, with unified, global network and SIP trunking solutions from a single provider
SD Worx chose Quendra / Colt for its high-performance, scalable services, geographical coverage, flexible SD WAN access options for SD Worx sites, and ability to provide a Direct Routing solution when SD Worx is ready to activate voice on Microsoft Teams.
A long-term Colt partner, Quendra designs and delivers IT and communications solutions for enterprise customers in Europe. To ensure the quality and reliability of its solutions, Quendra works with market leaders like Colt.
Business drivers – why SD WAN and SIP Trunking?
SD Worx, headquartered in Belgium, is an international provider of HR, payroll, recruitment and other technology solutions for people management. It has ~150 offices throughout Europe and a large team of developers in Mauritius.
When each country had its own network provider, managing the supplier contracts, diverse networking equipment and the network itself was a hefty burden.
In addition, all communications had to pass through and break out from the company’s data centre in Belgium, adding a degree of latency to the user experience.
At the same time, the company relied on a mix of ISDN and SIP trunks (with dozens of SBCs) from a variety of suppliers for voice services, including inbound calls to its customer service centre that make up ~75% of its voice traffic.
To drive cost savings, reduce management complexity and increase scalability, SD Worx wanted to replace its WAN connectivity, ISDN and SIP trunking services procured on a per-country basis with unified, global network and SIP trunking solutions from a single provider.
What did they need from their connectivity and voice services?
“We wanted a connectivity solution that was more manageable and would provide a consistently high level of performance.”
Daniel Cohen, Product Owner Network, SD Worx
“We wanted to move away from legacy ISDN connections and multiple SIP trunks and were after a single SIP trunking solution with managed SBCs that would support PSTN calling now, and get us on track for our planned migration to voice on Microsoft Teams.”
Peter Boers, System Engineer Voice, SD Worx
Daniel and Peter knew that working with a single provider would allow SD Worx to benefit from coherent solutions that can scale easily to support the company’s growth.
Why Colt?
SD Worx chose Colt for its high-performance, scalable services, geographical coverage, flexible SD WAN access options for SD Worx sites, and ability to provide a Direct Routing solution when SD Worx is ready to activate voice on Microsoft Teams.
The solution
Managed Colt SD WAN for corporate networking, powered by Versa Networks, with site access based on MPLS, IP Access or a combination of the two, depending on the requirements of each site. SIP Trunking with number porting and managed session border controllers (SBCs) for inbound and outbound voice.
The result
Simplified, secure managed networking and voice solutions that scale in line with business growth. SD WAN connects ~150 SD Worx offices to each other and to the corporate data centres. SIP Trunking enables calls to be made and received and lays the foundations for voice activation on Microsoft Teams.
The Colt difference
Smaller SD Worx sites connect to the SD WAN via Internet Access or MPLS. Larger sites have both, in an active-active configuration that allows traffic to travel over the most appropriate path. A single device at each site replaces previously separate routers and firewalls, reducing complexity.
“SD WAN also increases security. Now all our traffic is encrypted, even when it travels over the internet.”
Daniel Cohen, Product Owner Network, SD Worx
Peter appreciates the flawless handling of what was a large and challenging number porting project: “A Colt specialist spent months planning it and scheduled 90 porting windows to minimise disruption,” he says. “It all went amazingly smoothly.”
Activating voice on Microsoft Teams is the next step: the managed SBCs are Microsoft-certified, and Colt has set up Direct Routing to enable SD Worx to run a proof of concept (PoC).
“We’ve been very happy working with the exceptional Colt team and Quendra,” says Peter. “We’ve always been able to have open discussions and solve any issues jointly. It’s been a very positive experience,” adds Daniel.

COMPANY NAME
SD Worx
INDUSTRY
Human Resources
CHALLENGE
To drive cost savings, reduce management complexity and increase scalability
COLT SOLUTION
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