Specifications

• Flexibility & Scalability — You can easily add / remove extensions, remote users, SIP-trunks; no need for dedicated line-cards or major rewiring. vastresult.com+2Wikipedia+2

• Unified Network for Voice & Data — IP PBX uses your existing LAN/internet – no separate circuit-switched telephone wiring required. RingCentral+2diallink.com+2

• Lower & Predictable Costs — Reduced infrastructure, lower maintenance, and often cheaper trunking/long-distance calls (via VoIP) vs traditional PSTN. @ubiqcom+2calilio.com+2

• Modern Features & Integration — Easy to integrate with software (CRM, mail, cloud), support for remote workers, voicemail-to-email, auto-attendants, call-routing, conferencing, etc. diallink.com+2Wikipedia+2

• Better for Distributed / Multi-Site / Remote Work — Since it runs over IP, remote extensions (home offices, branch offices) can connect over Internet, not just physical lines — useful for modern-day work setups. bitvoice.in+2OnSIP+2

• Legacy infrastructure: If an organization already has lots of analog/digital phones, wired lines, and doesn’t want to re-wire or re-provision, they might continue with existing PBX.

• Simplicity: For very small setups or where basic calls suffice, old PBX might be simpler.

• Less dependency on network or Internet: Traditional PBX doesn’t depend on network bandwidth, SIP-trunks or Internet reliability — useful in areas with unstable Internet.

• For certain analog-phone/setups or proprietary digital-phone hardware — Digital-PBX (circuit-switched) may remain relevant.