Save the State: Data Synchronization Between Master and Backup Services

When the center is actively handling calls, minimizing any disruptions is key. You don’t want to have your agents stop, log out, log back in, then attempt to continue as they were. Doing that is an efficiency killer. To avoid this, multiple copies of a single service can be set to run on different servers. However, data has to be kept current in order to avoid losing information when switching services from backup to master.  Synchronization of information is absolutely required when we are attempting to set up redundancy for high availability in the call center.
Continue reading Save the State: Data Synchronization Between Master and Backup Services

Call Center Load Balancing with Kamailio

Session Initiation Protocol (SIP) hasn’t officially been crowned king of call center technologies, but it has become ubiquitous. The wide availability of SIP service providers and the way Asterisk is pushing Open Source technologies into the call center has made it undeniable. Especially now with the widespread adoption of Cloud-based call center software and remote agents, SIP is cementing its importance. Continue reading Call Center Load Balancing with Kamailio

Call Survival and Contact Center ACD

The rapid pace of innovation in Voice over IP (VoIP) technology and telephony software has been a blessing to contact centers around the world and has spurred a surge in deployment. The advantages of fully featured applications and low costs have been offset by the possibilities of service interruptions. The US patented Q-Suite Call Survival feature allows deployment of Asterisk based contact center ACD in a mission-critical and high value environment. Continue reading Call Survival and Contact Center ACD

The Challenge of VoIP System Failures Not Addressed by Most High Availability Designs

Hardware or software can fail at anytime and induce a system failure. It is not possible to reduce such failures to nil. When VoIP based systems experience such failures, it results in the loss of on-going calls. High availability (HA) or redundant systems cannot address this unless they are capable of restoring an on-going call without either one of the end-points re-initiating the call. Most high availability system for Session Initiation Protocol (SIP) based VoIP calls and their redundancy setup, deploy an immediate replacement of the failed component/sub-system to allow continued use of the system. It is good enough for many situations but it might not be adequate for mission critical applications when the HA cannot not restore on-going calls.

Imagine a scenario where an outside caller initiates a call and when it hits the demarcation point of the contact center installation. This could be a premise based contact center or a Cloud set up offering virtual contact center services. When the call setup reaches the intended peer and conversation starts, it is possible that your system, either Cloud based or on-premise solutions, could experience a failure. Once the system detects a failure, its high availability and redundant setup will kick-in and the system will be ready for future calls but what happens to the on-going call? They just die. This is the normal operating mode of traditional high availability systems including most high availability solutions offered for Asterisk. This issue becomes more critical for large contact centers using automatic call distribution (ACD) with significant traffic at any given time.

With contact center ACD, the importance of going beyond the traditional high availability is extremely important. Having the capability to keep calls alive through call survival is critical. This will allow the user to continue the phone conversation without the need for re-initiating the call. It is a sophistication in offering redundancy that goes beyond recognizing the need to bring into action the replacement software and hardware components. It introduces intelligence required in preserving all the on-going calls essential for mission critical systems.

The Differences in Call Survival and Call Recovery

While investigating High Availability (HA) in CTI and PBX systems you will often find mention of Call Recovery. Another term you run into is Call Survival, which is often used interchangeably with Call Recovery incorrectly. This is because each is a different approach to solving a problem. The problem being a failure which would interrupt the calls of a system.

With Call Survival when a failure happens the caller and callee do not have to take action to continue their call as it survives the failure. At a high level this is done by reacting to the failure quickly and re-routing the audio path around the failure.

With Call Recovery when a failure happens the recovery is different depending on the system. Sometimes the caller will need to initiate the redial the callee or it could be an automated process but the callee still have to answer this new call.

From a user perspective the better option is Call Survival as they may only experience a momentary interruption in their audio as the path is rerouted around the failure instead of having to re-initiate a call to recovery it.

The Q-Suite platform supports Call Survival with the help of the Overseer Watchdog providing HA for other services in addition to being one part of the Call Survival solution.