350+ terms
19 sections
Start here: the 5 terms business owners ask about most
If you only have a minute, these are the ones that come up in every contract.
01 | SIP Trunking
The digital line that connects your phone system to the outside world.
02 | Call Recording
Recording conversations for training, compliance, or quality assurance.
03 | Softphone
A phone app that runs on your computer or mobile device.
04 | Mobile Application
Your business number on your personal device, without mixing work and personal calls.
Calls reach the right person based on who's available, not who's next on the list.
Browse by Topic
📞 Core Telephony Concepts
Key terms: PSTN · ISDN · DID · DTMF · Caller ID · Extensions · Trunks · +11 more
🌐 VoIP Fundamentals
Key terms: VoIP · RTP · RTCP · Packetization · WebRTC · SBC · Gateway · +9 more
⚡ SIP Trunking
Key terms: SIP trunk · Concurrent calls · IP auth · STIR/SHAKEN · Emergency calling · +9 more
📬 Voicemail and Messaging
Key terms: Voicemail · Voicemail-to-email · Transcription · Visual voicemail · +7 more
🌊 Networking for VoIP
Key terms: QoS · NAT · VLAN · Latency · Jitter · Packet loss · Firewalls · STUN · TURN · +9 more
🎧 Devices and Hardware
Key terms: IP phones · Headsets · DECT phones · Conference phones · ATAs · +7 more
🔍 Quality Metrics and Troubleshooting
Key terms: MOS · One-way audio · CDR · Wireshark · SIP traces · Call drops · Echo · +8 more
⚙️ Deployment and Administration
Key terms: Auto-provisioning · Failover · High availability · Admin portals · +8 more
🏗️ Advanced and Carrier-Level
Key terms: Kamailio · Erlang formulas · Geo-redundancy · SIPREC · Load balancers · +8 more
🚀 Emerging Technologies
Key terms: AI transcription & Summary · Sentiment analysis · 5G · Edge computing · +8 more
🏢 PBX Systems
Key terms: Cloud PBX · IP PBX · Hosted PBX · Asterisk · FreePBX · 3CX · UCaaS · +8 more
🔗 SIP Protocol
Key terms: SIP · INVITE · REGISTER · SDP · 200 OK · Dialogs · Forking · +13 more
🔀 Call Routing and Features
Key terms: IVR · Call queues · Forwarding · Transfer · BLF · Presence · Call parking · +13 more
💬 Unified Communications
Key terms: UC · UCaaS · Video conferencing · Contact centres · Omnichannel · +10 more
🎵 Audio, Media and Codecs
Key terms: G.711 · G.722 · Opus · RTP · SRTP · Echo cancellation · Transcoding · +9 more
🔒 Security
Key terms: TLS · SRTP · VoIP fraud · Fail2Ban · ACLs · Brute force attacks · Encryption · +8 more
💰 Billing, Numbering and Telecom Business
Key terms: SLAs · E.164 · Number porting · TCO · Pricing models · Interconnection · +11 more
🔌 Integrations and APIs
Key terms: CRM integration · Microsoft Teams · REST API · Webhooks · SSO · +10 more
📋 Regulatory and Compliance
Key terms: GDPR · Recording consent · Emergency services · ILR · Data residency · +7 more
Definitions are just the entry point
Every glossary term links to where it matters: features that use it, providers that offer it, scenarios that need it.
📅 Ready to explore Cloud PBX for your business? Book a short call with a consultant. We cover Cloud PBX for businesses in Luxembourg, Belgium, France, and Germany.