Call lists, PDS and SIP

There are two ways how Voximplant can handle an outgoing call. First, the outgoing call can be initiated from JavaScript session created from the incoming call. That approach is used if you want to connect two or more people, forward call into a call center or implement any other “connect two persons” logic where and outgoing call is initiated as a response to the incoming call. Second, you can initiate outgoing call via the HTTP API. That approach is used if you want to initiate a call from your service or call multiple users. You can implement any call logic via HTTP API, but you also need to setup your own backend that will initiate calls, maintain the suitable number of simultaneous calls etc. For fast “out-of-the-box” experience we have a built-in “Call list” functionality that allows calling thousands of users with a few commands and without any backend of your own.

Operator status and temporary ban

While Voximplant ACD framework provides only essential call center backbone, it also has some out-of-the-box features for most popular use cases. One of such features is “Operator Status” that can be set to “Ready” if operator is available to handle a call, or any one of non-“Ready” if calls should not be forwarded to that operator.

IVR and operator skills

In a simple scenario all incoming user calls are evenly distributed among all available operators. But as a number of users grows, it became more convenient to direct specific requests to specific operators who can handle them better. This raises a number of questions: how to figure out user question and how to define which operator can answer that questions.

Waiting in a queue

Having a full control over an incoming and outgoing calls allows to implement any business needs. By default, a user will hear nothing while waiting in the queue, since we have not instructed VoxEngine to produce any audio. Good practice is to inform the user about his or her queue position and play some music to indicate the call in progress.

Handling a call disconnect

Since our cloud has separate “incoming” and “outgoing” call logs, we have full control over call disconnects. If a calling user or an operator disconnects, you can make decisions what to do next: play a notification message, call back, disconnect the remaining participants and so on. If the incoming or outgoing call is disconnected, the corresponding call object receives Disconnected event. Please note that an outgoing call can fail to connect (ex user not answered), in such case Failed event will be received instead of Disconnected.

Creating a call queue

The application we created at the previous step has a flaw: it’s unclear what to do if the second user calls while the first one is still talking to the operator. Our web and mobile SDK can accept multiple incoming calls (and the phone app supports two lines to demonstrate it), but a human operator can speak only with one person at a time. This can be solved by a call queue: while the operator speaks with a user, all other users are waiting in a queue, with optional waiting music being played and/or the synthesized message informing the users about the remaining waiting time.

Call queuing is required to process inbound calls to PBX or contact center, callers are put into queue where they wait for a free operator and listening to some music. IVR usually notifies a caller about his position in a queue and about estimate waiting time. Operators have controls to set their availability, because some time is required to put data about previous call before answering the next one. VoxImplant has all capabilities required to build contact center functionality including ACD (Automatic call distributor) that can be controlled using the ACD Module. In this tutorial we will build a simple queue that is being processed by operators with the same skill set.

Most of IVRs nowadays provide caller with the number of options that can be chosen in a multi-level menu. While this kind of IVR can be built using vanilla VoxEngine javascript code, it’s better to use helper module (Modules.IVR) we created to simplify the process. It lets developers build IVR menus in scenarios much faster and write less code for that. Let’s build the following IVR using the module: