IP telephony for office
Corporate PBX on Asterisk, 3CX or Yeastar. Call center, queues, IVR, CRM integration
IP telephony vs conventional PBX
A conventional PBX is copper wiring, analog or digital handsets, limited functionality. IP telephony is a local network, SIP phones or softphones, unlimited functionality.
IP telephony is cheaper to maintain, easier to scale (adding a subscriber = connecting a phone to the network), easily integrates with CRM (incoming call = client card on the screen).
Platforms
Asterisk is open source, free, with no functionality restrictions. Requires a qualified administrator. Suitable for large projects (50+ subscribers).
FreeSWITCH is an open source, more performant alternative to Asterisk. Used in large VoIP providers.
3CX is a commercial PBX with a free version for up to 8 subscribers. Easier to set up, good web interface. For medium offices (10-50 subscribers).
Yeastar is a commercial PBX, sold as hardware (P-series, S-series) or cloud. Easy setup, good support. For SMB.
Equipment
IP phones — Yealink (most popular, price/quality), Grandstream (budget), Fanvil (for hotels and specific tasks), Cisco (for large companies). Models from 2000 ₽ (basic) to 30,000 ₽ (premium with color screen and headset).
Gateways — for connecting analog lines or providers without SIP. AudioCodes, Grandstream, OpenVox. From 5000 ₽.
Headsets — for call centers and operators. Yealink, Jabra, Plantronics. From 2000 ₽.
Business functionality
Queues and call groups — distribution of incoming calls by departments or operators. Hold music, greeting, IVR (multi-level voice menu).
Call recording — for quality control or for controversial situations. Storage — locally or in the cloud, usually 3-12 months.
Integration with CRM (1C, Bitrix24, amoCRM) — incoming call automatically opens the client card. Outgoing call in one click from the card.
Mobile employees — softphone on the phone (Zoiper, Linphone, 3CX) for remote employees. Corporate communication without being tied to the office.
Connecting to telecom operators
SIP trunk is the main way to connect to an operator (Rostelecom, MTT, Beeline, Megafon). The operator issues a number or a pool of numbers, SIP settings are in the PBX.
Backup channel is from two different operators with automatic switching when the main one fails.
8-800 numbers are free for callers. Cost of the number is from 2000 ₽/month, incoming — per minute.