- Ad Hoc On-Demand Distance Vector
- Adaptive Differential Pulse Code Modulation
- Analog Display Service Interface
- Analog Roaming
- Answering Machine
- Antenna Array
- Asynchronous Transfer Mode
- Authentication Center
- Auto Dialer
- Automatic Call Distributor
- Automatic Location Identification
- Automatic Number Identification
- Band
- Base Station Controller
- Bell 103
- Bell 212A
- Bell Operating Company
- Bellhead
- Blue Box
- Bluejacking
- Business Support System
- Call Control
- Call Detail Record
- Call Forwarding
- Caller ID
- Caller Ringback Tone
- Candy Bar Phone
- Carrier
- Cell On Wheels
- Cell Phone Spying
- Cellular
- Cellular Phone Hacking
- Central Office
- Central Office Exchange Service
- Channel Bank
- Code Division Multiplexing
- Communication Media
- Competitive Local Exchange Carrier
- Computer Telephony Integration
- Concatenated Short Message Service
- CoolTalk
- Customer Premises Equipment Device
- Dark Fiber
- Deep Dialing
- Delay Distortion
- Delta Channel
- Demand Assigned Multiple Access
- Demarcation Point
- Demon Dialer
- Dialed Number Identification Service
- Digital Access and Cross-Connect System
- Digital Enhanced Cordless Telecommunications
- Digital Loop Carrier
- Digital Video Broadcasting-Satellite Second Generation
- Direct Inward Dialing
- Dual-Mode Device
- Dual-Tone Multifrequency
- E.164
- Echo Cancellation
- Eight-to-Fourteen Modulation
- European Telecommunications Standards Institute
- Evolution-Data Optimized
- Facsimile Machine
- Fast Infoset
- Feature Group D
- Fiber to the Home
- Firmware Over-The-Air
- Flight Mode
- Frequency-Shift Keying
- G.711
- G.722
- G.723
- G.726
- G.727
- G.728
- Gatekeeper Transaction Message Protocol
- Global Area Network
- Global Internet Exchange
- Google Talk
- Hairpin
- Handoff
- Handsfree
- Hayes Smartmodem
- High-Performance Radio Local Area Network
- I-Mode
- Incumbent Local Exchange Carrier
- Integrated Services Digital Network
- Interexchange Carrier
- International Mobile Equipment Identity
- International Mobile Subscriber Identity
- Internet Art
- Internet Phone
- Internet Protocol Private Branch Exchange
- Internet Protocol Telephony
- Internet Telephony
- Internet Telephony Service Provider
- IP Multimedia Subsystem
- iPhone 3G
- Jitter (VoIP)
- Land Line
- Last Mile Technology
- Leased Line
- Local Access and Transport Area
- Local Exchange Carrier
- Location Based Services
- Main Distribution Frame
- Mean Opinion Score
- Measured Telephone Service
- Medium Dependent Interface Crossover
- MERA VoIP Key System
- MERA VoIP Transit Softswitch
- Microcell
- Mobile Location Protocol
- Mobile Marketing Association
- Mobile Network Operator
- Mobile Phone Virus
- Mobile Station International Subscriber Directory Number
- Mobile Switching Center
- Mobile Virtual Network Operator
- Multi Channel Television Sound
- Multiplexing
- Next Generation Network
- Node Port
- Nokia N8
- Numbering Plan
- Optical Local Exchange Carrier
- Phablet
- Phase-Shift Keying
- Phreaking
- Plain Old Telephone Service
- Predictive Dialer
- Private Access DSL
- Private Automatic Branch Exchange
- Public Switched Telephone Network
- Punchdown Block
- Q Signaling
- Q.931
- Qi
- Radio Frequency Identification Reader
- Real-Time Transport Protocol
- Reed-Solomon Codes
- Registered Jack-45
- Ringtone
- Second Generation Wireless
- Service Switching Point
- Session Controller
- Session Initiation Protocol Trunking
- Short Message Service Center
- Signal Strength
- Signaling System No.7
- Spatial Division Multiple Access
- Speed Dial
- Sub-band Adaptive Differential Pulse Code Modulation
- Synchronous Digital Hierarchy
- T-1 Carrier
- T1 Line
- Tag Switching (Label Switching)
- Telecommunications
- Telecommunications Equipment Manufacturer
- Telephone Company
- Telephone Number Mapping
- Telephony Server Application Programming Interface
- TEMPEST
- Time Division Duplex
- Transponder
- Unbundled Network Elements-Platform
- User Agent Client
- V.22
- V.22bis
- V.34
- V.35
- V.42
- V.90
- Virtual Private Branch Exchange
- Voice 2.0
- Voice Call Continuity
- Voice Operated Switch
- Voice Over Instant Messenger
- Voice Over Internet Protocol Caller Identification
- Voice Over Internet Protocol Phone
- Voice Over IP Security Alliance
- Voice Over Wireless Fidelity
- Voice Peering
- Voice Search
- VoIP Trunk Gateway
- Wide Area Telecommunication Service
- Wide Area Telephone Service
- Wideband Voice
- Wi-Fi Cell Phone
- Wi-Fi Multimedia
- Windows NT LAN Manager
- Wrap Plug
- xDSL
- Yagi Antenna
- ZMODEM
