Knowledge Base Article-Call Centre Load Testing

Contact Centre / Call Centre Performance Testing and Load Testing

This is short article about Performance & Load Testing a Contact / Call Centre (referred to subsequently as Contact Centre). Contact Centre performance often refers to how quickly call centre personnel answer a call or the sound quality of the call. This article is about neither.  It is about how the software and infrastructure perform, how quickly a telephone call is routed and how much capacity can your Contact Centre handle.

A Contact Centre involves a complex blend of technologies and protocols.  A typical Contact Centre might communicate with its customers via phone calls, emails, Texts (SMS), online and faxes.  The Contact Centre will need to route these communications to and from the most appropriate and available person (Agent).  The Contact Centre will also be collecting data about the customer interactions, providing contact information to the Agents and providing reports and analysis.

In order to Load Test a Contact Centre the following key items need to be considered:

* Generating inbound phone call traffic
* Generating outbound phone call traffic
* Agent interactions with the Contact Centre application
* Agent interactions with the customer via the multiple medias that may be supported
* Routing of phone calls to appropriate Agent
* Generating a multiplicity of reports such as Agent, Supervisor and System
* Deployment of new or modified Contact Centre configurations
* Management and maintenance of the heirarchical structure of Agents, Supervisors, Groups and Queues


Before conducting a Performance Test it is good practice, as in any other performance testing exercise, to understand the volumetrics of the Call Centre being tested.  There is no point running a Performance Test against aspects of the application that are only rarely used, however it is imperative that those aspects of the application which are heavily used are thoroughly tested.


In order to determine these volumetrics you should consider the following (amongst many others):

* The number of Agents that will be concurrently logged on
* The rate at which Agents log on at
* The rate at which phone calls are made to the Contact Centre
* The rate at which phone calls are made from the Contact Centre
* The number of concurrent phone calls
* How many calls per hour should each Agent handle
* The rate at which emails are made to the Contact Centre
* The rate at which emails are made from the Contact Centre
* The number of concurrent emails
* How many emails per hour should each Agent handle
* .. and so on for all media types supported by the Contact Centre


Testing Performance have found that there a number of protocols used in Contact Centres, the most popular being SIP (Session Initiation Protocol) which handles the phone calls, Web Services, HTTP/HTML and SMTP.  We usually use HP's LoadRunner for performance testing, however, at the time of writing this article, LoadRunner does not directly support SIP, this means that a number of tools are required, one to handle the SIP traffic and LoadRunner for most of the other traffic. Empirix, one of the lesser known performance testing tools, is well placed to performance test a Contact Centre in that the Empirix Hammer product can generate SIP requests.

We have found the performance testing of Contact Centres to be very challenging yet very satisfying and rewarding.

From time to time this article will be updated and enhanced, should you be interested in learning more or would like Testing Performance to undertake performance testing of your Contact Centre please feel free to contact us regarding this service or to have a chat about our software testing services.