A softphone is a software program for making telephone calls over the Internet using a general purpose computer, tablet or smartphone, rather than using dedicated hardware. Often designed to behave like a traditional telephone, with a display panel and buttons for user interaction.

Learn More: Back to Basics, What is a Softphone and How to Leverage It?

• VoIP.ms Softphone — Official mobile app with push notifications and SMS support (Android & iOS)
• Zoiper — Multi-platform SIP and IAX softphone (Windows, macOS, Android, iOS, Linux)
• Bria Solo / Bria Teams — Desktop and mobile softphones with call control and team messaging (CounterPath)
• Linphone — Open-source SIP softphone supporting voice, video, and messaging (all platforms)
• MicroSIP — Lightweight Windows/macOS/Linux SIP client
• Acrobits — Certified mobile SIP client for iOS and Android

An Analog Telephone Adapter (ATA) is a device used to connect one or more standard analog telephones to a digital telephone system (such as Voice over IP) or a non-standard telephone system. ATAs allow you to keep using your existing analog phones on a VoIP network.

Learn More: Back to Basics - What is an ATA?

• Grandstream HT802 — 2-port ATA with T.38 faxing, SIP TLS, and SRTP encryption
• Grandstream HT802V2 — Updated HT802 with enhanced performance and security
• Polycom OBi300 — Single-port ATA with T.38 fax support, ideal for home office use
• Mediatrix C7 / 4100 Series — Enterprise-grade VoIP adapters, up to 24 analog ports, TLS/SRTP
• ReadyNet AC1000MS / AC1300MS — Dual-band Wi-Fi router with integrated 2-line or 1-line SIP ATA

An IP Phone uses Voice over IP (VoIP) technologies, allowing telephone calls to be made over an IP network such as the Internet, instead of the ordinary PSTN system. IP phones connect directly to your network and require no adapter.

Learn More: Back to Basics - What is an IP Phone?

• Grandstream GXP2170 — High-end IP phone with color display and advanced telephony features
• Yealink SIP-T46U — Professional business phone with color display and advanced call management
• Fanvil V66 Pro — Premium phone with 7-inch rotatable touch screen and dual-band Wi-Fi 6
• Cisco 68XX & 88XX Series — Business phones ranging from affordable to HD video-capable models
• Fanvil V67 — Executive phone with adjustable touch screen and colorful keypad lighting
• Grandstream GRP2615 — Carrier-grade enterprise phone with advanced security features

An acronym for Private Branch eXchange. PBX telephone systems support incoming calls from the outside PSTN, placing calls between extensions, conferencing, voicemail, and a variety of other advanced telecommunication functions. PBX systems range from open-source software solutions to dedicated hardware appliances.

Learn More: Back to Basics - What is a PBX?

• Asterisk — The world's most widely used open source telephony platform (Linux/UNIX, since 1999)
• FreePBX — Open source, web-based PBX built on Asterisk — easy to manage at any scale
• 3CX Phone System — Software-based IP PBX with complete Unified Communications out of the box
• VitalPBX — Free Linux/Asterisk-based communications system for on-premise or hosted deployments
• FusionPBX — Full-featured multi-tenant PBX and voice switch for FreeSWITCH
• Yeastar S/P-Series — SMB-focused VoIP PBX with enterprise-grade UC capabilities