Creating a call center test bench for load balancing Asterisk servers in a cluster

Abstract

The article deals with the issues of increasing throughput in call centers. The current solution is to cluster call servers and evaluate their characteristics to ensure efficient operation and the necessary fault tolerance. It is shown that one of the main aspects of the quality functioning of the call center is load balancing of servers in the cluster. The features of the call-center modeling process are considered. The organization scheme of the call center of the company and the network model of the call center have been created. Virtualization technology was used to create a network model of a call center. The VMWare ESXI 6.7 hypervisor and the vCenter client were used as a network configuration platform. An analysis of load balancing was carried out using different algorithms and strategies. Asterisk PBX was configured and a server cluster was created. A test bench was developed and configured using the Zabbix open source product to explore a cluster of call servers. A bandwidth characteristic for the Asterisk _1 server and a network map were obtained, which actually represents a simulated structure of the call center network. The process of load testing on three Asterisk servers and the implementation of Zabbix load balancing capabilities are shown. A custom SIPp session script has been created for accepting calls and load testing. The number of calls that the call center is able to handle is calculated. It has been determined that a single Asterisk server with its current settings can handle a maximum of 915 concurrent calls. The process of load balancing on a cluster of SIP servers has been launched. A cluster of Asterisk servers has been found to be capable of handling 2550 simultaneous calls.