The primary purpose of an Auto attendant is to direct a caller to an appropriate person or department based on the caller's input to the provided menu options. Callers can be directed to specific people within your organization, to Call queues where they wait to talk to the next available agent, or to voicemail. Different call routing options can be specified for business hours, off hours, and holidays.

Menu prompts can be created by using text-to-speech (system-generated prompts) or by uploading a recorded audio file. Speech recognition accepts voice commands for hands-free navigation, but people calling in can also use the phone keypad to navigate menus.

Each Auto attendant has a specific language and time zone. If you do business in multiple languages or multiple parts of the world, you can create as many different Auto attendants as you need to accommodate your callers.

For each Auto attendant, you can configure an operator. While you can configure operator calls to go to various destinations, the operator feature is designed to allow callers to talk to a specific person in your organization who can help them.

Auto attendants can be configured to allow callers to search your organization's directory, either by name or by extension number. Within an Auto attendant, you can specify who is available for the directory search by choosing groups of users to include or exclude. (This is known as dial scope.)

Callers can reach an Auto attendant either by direct phone number, if configured, or by being redirected from another Auto attendant or a Call queue.

An Auto attendant is best for your departmental needs if you need to provide:

• A greeting message.
• Automated Holiday greetings and hours
• Voice and dial key menu options for callers to reach different destinations at the push of a button
• Automated after hours call flow

A Call queue is analogous to a waiting room in a physical building. Callers wait on hold while calls are routed to the agents in the queue. Call queues are commonly used for sales and service functions. However, Call queues can be used for any situation where the number of calls exceeds your internal capacity, such as a receptionist in a busy facility.

Call queues allow for specific routing of calls in cases where the total number of callers in the queue or the wait time exceeds the limits that you specify. Calls can be routed to specific people, voicemail, other Call queues, or Auto attendants.

Like Auto attendants, Call queues each have a language setting. You can use different Call queues if you do business in multiple languages. Agents can be members of more than one queue if they're multi-lingual.

For each Call queue, you can specify if agents in the queue can opt out of taking calls and if calls should be routed to them based on their presence indication in Teams.

You can assign a phone number to a Call queue, however Call queues don't provide separate call routing for off hours and holidays. Unless your Call queue is staffed 24/7, we recommend assigning the phone number to an Auto attendant that redirects to the Call queue during business hours.

A call queue is best for your departmental needs if you need to provide:

• A greeting message.
• CallerID for Callbacks
• Music while people are waiting on hold in a queue.
• Call routing - in First In, First Out (FIFO) order - to agents.
• Handling options for queue overflow and timeout.

Role Based Account (RBA)

A Role Based Account is a User object in Active Directory. This type of account can be an Agent for a call queue or a menu destination for an auto attendant. It can also be used as a voicemail target.

Traditionally a Role Based Account is used as a stand alone account that is assigned a phone number and can take the role of a front desk receptionist.

Instructions for creating an RBA can be found here: https://answers.uillinois.edu/34169

A role based account is best for your departmental needs if you need to provide: 

• A direct phone line to a person or set of people
• Call Delegation with Team call groups and delegates
• Centralized place for Voicemail