Glossary / Integrations and APIs
🔌 Integrations and APIs covers how a Cloud PBX connects with other business software such as CRM systems, Microsoft Teams, and custom applications. This section contains 18 terms that explain the protocols, standards, and methods used to link your phone system with the rest of your digital workplace.
On this page: CRM Integration · CTI · TAPI · REST API · Webhook · WebSocket · AMI · ARI · AGI · Microsoft Teams Integration · Direct Routing · Operator Connect · Zoom Phone · Calendar Integration · Directory Integration/LDAP · SSO · Zapier/Make · Screen Pop
CRM Integration
Connecting your phone system to a Customer Relationship Management tool (such as Salesforce, HubSpot, or Odoo) so that call data flows automatically between the two. When a customer calls, the CRM can display their record on screen. When the call ends, the system can log the call, its duration, and any notes directly in the CRM.
Related: Screen Pop · CTI · Analytics
CTI (Computer Telephony Integration)
A technology that allows computers and phone systems to work together. CTI enables features like click-to-call from your desktop, automatic screen pops when a call arrives, and call control (answer, hold, transfer) directly from your computer screen. It is the foundation for most modern PBX integrations with business software.
Related: TAPI · Screen Pop · CRM Integration
TAPI (Telephony Application Programming Interface)
A Microsoft Windows standard that allows software applications to control telephone functions. TAPI was widely used with on-premise PBX systems to enable click-to-dial and call logging from Windows applications. It is less common in modern Cloud PBX setups, where REST APIs and WebSockets have largely replaced it.
Related: CTI · REST API
REST API (Representational State Transfer API)
A standard way for software to communicate over the internet using simple HTTP requests (GET, POST, PUT, DELETE). Cloud PBX providers offer REST APIs so that developers can build custom integrations: retrieve call logs, create extensions, trigger calls, or manage voicemail programmatically. REST APIs are the most common integration method for modern cloud services.
Related: Webhook · WebSocket · API
Webhook
An automated message sent from the PBX to another application when a specific event occurs. For example, the PBX can send a webhook to your CRM every time a call ends, delivering call details in real time. Unlike polling (repeatedly asking "any new data?"), webhooks push data instantly when something happens. They are efficient and simple to set up.
Related: REST API · Zapier/Make
WebSocket
A communication protocol that keeps a persistent, two-way connection open between a client (such as a web browser) and a server. In PBX systems, WebSockets enable real-time features like live call status updates, instant presence changes, and browser-based softphones (WebRTC). Unlike REST APIs, which require a new request for each action, WebSockets stream data continuously.
Related: REST API · WebRTC
AMI (Asterisk Manager Interface)
A control interface specific to Asterisk-based PBX systems. AMI allows external programs to send commands (originate a call, transfer, hang up) and receive real-time events (call started, call ended, queue status) over a TCP connection. It is powerful but complex, and is being gradually replaced by the newer ARI in modern Asterisk deployments.
Related: ARI · AGI · Asterisk
ARI (Asterisk REST Interface)
A modern API for Asterisk PBX that gives developers fine-grained control over calls using standard REST and WebSocket protocols. With ARI, you can build custom call applications: interactive menus, call recording triggers, or intelligent call routing based on external data. ARI is the recommended way to develop on Asterisk today.
Related: AMI · REST API · Asterisk
AGI (Asterisk Gateway Interface)
A scripting interface for Asterisk that lets external programs control the flow of a single call in real time. When a call hits an AGI step in the dial plan, Asterisk launches your script (written in Python, PHP, or another language), which can play prompts, collect input, query a database, and route the call accordingly.
Related: AMI · ARI · IVR
Microsoft Teams Integration
Connecting a Cloud PBX to Microsoft Teams so that users can make and receive external phone calls directly within the Teams app. This means employees use a single application for both internal collaboration and external calling. The two main integration methods are Direct Routing and Operator Connect.
Related: Direct Routing · Operator Connect · Microsoft Teams
Direct Routing
A Microsoft Teams integration method where your PBX connects to Microsoft's phone system through a certified Session Border Controller (SBC). Your PBX handles the SIP trunk and call routing, then bridges those calls into Teams. Direct Routing gives you full control over call routing, number management, and provider selection.
Related: Microsoft Teams Integration · Operator Connect · SBC
Operator Connect
A Microsoft Teams integration method where your telecom provider appears directly in the Teams admin centre. Instead of managing an SBC yourself, you select your provider from a list, and Microsoft and the provider handle the technical connection. Operator Connect is simpler to set up than Direct Routing but offers less customisation.
Related: Direct Routing · Microsoft Teams Integration
Zoom Phone
Zoom's built-in cloud phone system that turns the Zoom application into a full business phone. Some Cloud PBX providers can integrate with Zoom Phone through SIP peering, allowing calls to flow between your PBX and Zoom users. This is useful for organisations that have standardised on Zoom for video meetings.
Related: Microsoft Teams Integration · SIP Trunk
Calendar Integration
Connecting your PBX to a calendar system (such as Google Calendar or Microsoft Outlook) so that your phone behaviour changes based on your schedule. For example, during a meeting marked "busy," calls can be forwarded to voicemail automatically. Calendar integration helps reduce interruptions and improves presence accuracy.
Related: Presence · Directory Integration/LDAP
Directory Integration / LDAP
Syncing your PBX user list with a central directory service such as Microsoft Active Directory or an LDAP server. When a new employee is added to the company directory, their PBX extension and voicemail are created automatically. When they leave, their account is disabled. This eliminates manual user management and reduces errors.
Related: SSO · Calendar Integration · Provisioning
SSO (Single Sign-On)
A system that lets users log in to the PBX web portal, softphone, or admin interface using their existing company credentials (such as Microsoft 365 or Google Workspace). SSO eliminates the need for separate passwords, improves security, and simplifies user management for IT teams.
Related: Directory Integration/LDAP · SSO Feature
Zapier / Make (Automation Platforms)
No-code automation tools that connect your PBX to hundreds of other applications without writing code. For example, you can create a workflow that sends a Slack message whenever a call is missed, or adds a new contact to your CRM when an unknown number calls. These platforms use webhooks and APIs to link services together.
Related: Webhook · REST API · CRM Integration
Screen Pop
A notification that appears on an agent's computer screen when a call arrives, showing information about the caller. The screen pop typically displays the caller's name, company, previous interactions, and open support tickets pulled from the CRM or helpdesk. Screen pops help agents handle calls faster and provide more personalised service.
Related: CTI · CRM Integration · Call Queue
Related Sections
🔗 SIP Protocol — The signalling standard behind VoIP calls
📞 Call Features — IVR, call queues, presence, and more
⚙️ Deployment and Administration — Provisioning, dial plans, and system management
🔒 Security — Encryption, authentication, and fraud prevention
📅 Ready to explore Cloud PBX for your business?
Start with the provider comparisons or feature guides. If you want expert help, book a short call with a consultant.
Made with Bullet