VoIP migration planning: a staged cutover guide
Move from legacy telephony to VoIP with inventory, dependency mapping, pilot testing, staged cutover, rollback, and user support.
From the blog
VoIP Fundamentals
Clear explanations of VoIP, SIP, RTP, codecs, phone numbers and the technologies behind modern voice.
VoIP fraud prevention and toll-fraud controls
Reduce VoIP fraud risk with strong authentication, destination controls, rate limits, monitoring, alerting, and incident response.
VoIP high availability and failover
Design and test VoIP failover for PBXs, SBCs, carriers, DNS, media paths, power, and connectivity without relying on untested assumptions.
VoIP documentation checklist
Create the network, numbering, routing, security, carrier, endpoint, and recovery documentation needed to operate a VoIP service.
Voicemail systems: storage, access, and reliability
Plan VoIP voicemail with greetings, storage, message waiting indicators, email delivery, retention, permissions, and recovery testing.
Voice quality testing: a practical test plan
Test VoIP quality with repeatable calls, realistic paths, controlled impairments, user scenarios, and measurable acceptance criteria.
SIP timers: retransmissions, timeouts, and session refreshes
Understand SIP transaction timers, retransmissions, session timers, and why slow or lossy networks can cause calls to fail.
IPv6 for VoIP: dual-stack signalling and media
Prepare VoIP systems for IPv6 by checking DNS preference, SIP transport, SDP addresses, firewalls, NAT differences, and endpoint support.
VoIP dial plans: routing rules that remain maintainable
Design dial plans with clear normalisation, permissions, emergency handling, least-cost routing, and predictable test cases.
VoIP call transfers: blind, attended, and consultative transfer
Learn how blind and attended transfers work, which SIP transactions are involved, and how to troubleshoot failed transfers.
VoIP call recording: architecture and operational checklist
Understand call recording capture points, storage, access control, retention, quality, and operational risks in VoIP systems.
VoIP call queues: design, metrics, and troubleshooting
Plan call queues with routing strategy, agent states, overflow, announcements, service levels, and meaningful operational metrics.