Call features
- Authentication
- Automated Attendant
- Blacklists
- Blind Transfer
- Call Detail Records
- Call Forward on Busy
- Call Forward on No Answer
- Call Forward Variable
- Call Monitoring
- Call Queuing
- Call Recording
- Call Routing (DID & ANI)
- Call Snooping
- Call Transfer
- Call Waiting
- Caller ID
- Caller ID Blocking
- Caller ID on Call Waiting
- Conference Bridging
- Database Store / Retrieve
- Database Integration
- Dial by Name
- Direct Inward System Access
- Distinctive Ring
- Distributed Universal Number Discovery (DUNDi™)
- Do Not Disturb
- E911
- Flexible Extension Logic
- Interactive Directory Listing
- Interactive Voice Response (IVR)
- Local and Remote Call Agents
- Macros
- Music On Hold
- Music On Transfer:
- Flexible Mp3-based System
- Random or Linear Play
- Volume Control
Call features
- Protocol Conversion
- Remote Call Pickup
- Remote Office Support
- Roaming Extensions
- Route by Caller ID
- SMS Messaging
- Supervised Transfer
- Three-way Calling
- Time and Date
- Transcoding
- Trunking
- VoIP Gateways
- Voicemail:
- Visual Indicator for Message Waiting
- Voicemail to email
- Voicemail Groups
Codecs
- ADPCM
- G.711 (A-Law & μ-Law)
- G.722
- G.723.1 (pass through)
- G.726
- G.729 (through purchase of a commercial license)
- GSM
- iLBC
- Linear
Protocols
- IAX™ (Inter-Asterisk Exchange)
- H.323
- SIP (Session Initiation Protocol)
PRI Protocols
- 4ESS
- BRI (ISDN4Linux)
- DMS100
- EuroISDN
- Lucent 5E
- National ISDN2
- NFAS
