CTS - Computer Technology Specialists
VoIP vs Traditional Phone Systems
Traditional PSTN and ISDN business phone systems are being retired across Australia — NBN's circuit switch-off has accelerated this shift, making VoIP and Microsoft Teams Phone the standard for Melbourne business communications.
Melbourne IT support with visible local credentials
CTS - Computer Technology Specialists has supported Melbourne SMBs since 2000. Contact: 1300 790 780, hello@cts.au, L30 - 35 Collins St Melbourne 3000.
Certifications, affiliations and technology partners
Microsoft Partner, ACSC Essential Eight aligned, ISO 27001 practices, NBN Business Accredited Adviser, Cisco Partner, Dell Partner, HPE Partner, Arcserve Partner, Broadcom Partner, Kyocera Partner.
How traditional phone systems work — and why they're ending
Traditional business phone systems — PABX hardware connected to PSTN or ISDN lines — route calls through the public switched telephone network using dedicated circuit-switched connections. These systems required on-premises hardware, physical handsets, and ISDN lines from a telco. Telstra has been migrating ISDN services to IP-based alternatives since 2018, and the NBN rollout has accelerated the retirement of PSTN copper circuits. Businesses still running ISDN lines are operating on infrastructure that is being progressively decommissioned — forced migrations are creating opportunities to move to more capable, lower-cost alternatives.
How VoIP and cloud calling work
Voice over IP (VoIP) converts voice calls into data packets transmitted over an internet connection, eliminating the need for dedicated phone lines. Cloud-based VoIP systems host the calling platform in the cloud — the business connects softphone apps on PCs and mobiles, or VoIP handsets, to the cloud platform over the internet. This removes the on-premises PABX hardware and the associated maintenance cost. Call routing, voicemail, IVR menus, hunt groups, and call recording are all managed in a web portal rather than through hardware configuration.
Microsoft Teams Phone for Melbourne businesses
Microsoft Teams Phone adds full PSTN calling capability to Microsoft Teams. Calls can be made and received through the Teams app on any device — PC, Mac, iOS, Android — using either Microsoft's Calling Plans (where Microsoft is the carrier) or Direct Routing (where an existing Australian carrier is connected to Teams via a Session Border Controller). For Melbourne businesses already using Microsoft 365, Teams Phone unifies communication into a single platform — no separate desk phone system, no additional apps, and administration through the existing Microsoft 365 admin centre. CTS deploys Teams Phone as the standard recommendation for most Melbourne SMBs.
Cost comparison — traditional vs VoIP
Traditional PABX systems carry high upfront hardware costs (typically $5,000-30,000+ depending on size), per-handset costs, ISDN line rental, and ongoing hardware maintenance. VoIP and Teams Phone eliminate the hardware capital cost, replacing it with a per-user monthly licence and carrier call costs. For most Melbourne SMBs, the total monthly cost of Teams Phone is lower than ISDN line rental alone, while providing significantly more capability — softphones, mobile apps, voicemail transcription, call recording, and IVR menus.
Number porting and migration considerations
Existing business phone numbers can be ported to VoIP providers or to Microsoft Teams Phone Calling Plans. Australian number porting typically takes 4-10 business days, during which calls should be diverted to avoid interruption. Before porting, confirm that all numbers are active on the current account and that there are no pending disconnections. For Direct Routing deployments (connecting your existing carrier to Teams), no porting is required — calls continue routing through the existing carrier. CTS manages the porting process for Teams Phone deployments and coordinates with carriers to minimise transition risk.
How CTS migrates Melbourne businesses to Teams Phone
CTS handles the full Teams Phone deployment: licence assignment, Direct Routing or Calling Plan configuration, auto-attendant and call queue setup, number porting, handset configuration (where physical handsets are required), user training, and post-cutover support. For managed IT clients already using Microsoft 365, Teams Phone deployment typically completes within two to four weeks. CTS also manages ongoing administration — adding new users, adjusting call routing, and managing carrier relationships.
Frequently asked questions
Can we keep our existing phone numbers when moving to Teams Phone?
Yes. Australian business phone numbers can be ported to Microsoft Teams Phone through Microsoft's Calling Plans or maintained with your existing carrier through Direct Routing. CTS manages the porting process and coordinates with your carrier to minimise disruption during the transition.
What happens to our existing handsets when migrating to Teams Phone?
Existing analogue or digital handsets generally cannot be reused with Teams Phone, which requires SIP-compatible handsets or softphone apps. CTS assesses your current hardware during the migration scoping and recommends compatible handsets where physical devices are still required — many users transition to softphone apps on PC and mobile instead, eliminating handset cost entirely.