How Business VoIP Works and Why It Is Better Than a Traditional Phone Line

Traditional Phone Lines Are Disappearing

The copper network that carries traditional analogue phone lines across Australia is being progressively decommissioned as the NBN rollout completes. Telstra has announced the copper network will be fully shut down, and businesses still relying on PSTN or ISDN connections will need to transition.

VoIP (Voice over Internet Protocol) is the replacement technology — and for most businesses, it is not just a like-for-like substitution. VoIP phone systems offer features and flexibility that traditional phone systems simply cannot match.

How VoIP Actually Works

VoIP converts voice into digital data packets and transmits them over the internet — the same way email or a web page travels. Instead of a dedicated copper circuit between two phones, a VoIP call uses your existing internet connection.

The quality of a VoIP call depends on:

• BandwidthVoice calls use roughly 100 Kbps per concurrent call, so a 50 Mbps connection can handle hundreds of calls simultaneously
• LatencyCall quality degrades with high latency — a quality business internet connection with QoS configured for VoIP traffic maintains the low latency required
• JitterIrregular packet delivery creates audio artefacts — a well-configured QoS policy on your network prioritises VoIP packets to prevent this

What VoIP Does That Traditional Phone Systems Cannot

Calls from anywhere. A VoIP softphone on a laptop or smartphone extends your business phone system to wherever your staff are. Calls to your business number ring on the office phone and the mobile simultaneously. Staff working from home answer as if they are in the office.

Auto-attendant and IVR. "Press 1 for sales, 2 for support" functionality is standard in virtually all VoIP platforms and requires no additional hardware. Traditional phone systems required expensive PABX equipment to achieve the same result.

Call recording. Recording calls for training, compliance, or dispute resolution is a standard feature in most VoIP systems. Storing call recordings in the cloud means they are searchable and accessible from anywhere.

Conference calling. Multi-party conference calls — again, standard in VoIP systems and requiring no bridge dial-in or extra cost.

CRM integration. Many VoIP platforms integrate with CRM systems so incoming calls are automatically matched to customer records, logging call history and triggering workflows.

The Cost Comparison

A traditional multi-line phone system for a ten-person office typically involved significant upfront PABX hardware costs, per-line rental fees, and per-minute call costs. A comparable VoIP system costs $20–$40 per user per month on a hosted platform with no hardware capital expense, and calls to Australian numbers are typically included in the monthly plan.

What Businesses Should Consider Before Switching

• Internet quality: VoIP requires a reliable connection. Businesses with internet reliability issues should address connectivity before switching
• Network QoS: VoIP traffic should be prioritised on the router and switch to prevent call quality issues during busy periods
• Number porting: Existing phone numbers can be ported to most VoIP providers

VoIP Quality: What Determines Call Quality

Understanding what determines VoIP call quality helps explain both why VoIP performs well and what causes the problems some businesses experience.

Codec. The codec converts audio to digital packets and back. Modern codecs — particularly Opus and G.722 — provide HD-quality audio that is noticeably clearer than traditional landlines. Older codecs like G.711 provide standard quality, and G.729 (a compressed codec used to save bandwidth) can sound thin if overused. Your provider and phones determine which codecs are available.

Jitter. Jitter is variation in packet arrival timing. Voice packets need to arrive at consistent intervals to sound smooth. High jitter produces choppy audio — words drop out or sound robotic. Jitter is caused by network congestion, poor Wi-Fi, or saturated internet connections. QoS configuration on the business router prioritises voice packets to reduce jitter.

Packet loss. Lost packets mean lost audio. Even a 1–2% packet loss rate on a voice call is perceptible. Packet loss is caused by congestion on the network path between your office and the VoIP provider. A business-grade internet connection with adequate headroom for voice traffic prevents this.

Latency. The delay between speaking and the other party hearing. Under 150ms is imperceptible; 150–300ms is noticeable but workable; above 300ms creates an awkward echo effect. Cloud VoIP services routing through geographically close servers (Australian-based) have lower latency than services routing internationally.

Microsoft Teams Phone vs Traditional VoIP

Two distinct approaches to cloud telephony are common in Brisbane and Gold Coast businesses:

Traditional VoIP (e.g., 3CX, FreePBX, MyNetFone, Aussie Broadband Business Voice). A traditional VoIP system replicates the function of a physical PBX in the cloud. Extensions, ring groups, IVR menus, call queues, hold music, call recording — all the features of a business phone system, delivered via internet. Compatible with desk phones (physical handsets) and softphone apps.

Microsoft Teams Phone. Uses Microsoft Teams as the phone system. Staff make and receive calls through the Teams app on their computer or mobile. Calling requires either Microsoft Calling Plans (dial tone from Microsoft) or Direct Routing (connecting an existing telephone number through a SIP provider). Deeply integrated with Teams calendar, contacts, and collaboration — ideal for businesses already using Teams heavily.

The choice between them depends on: how embedded Teams is in daily workflows (if Teams is used for everything, Teams Phone is a natural extension), whether physical desk phones are required (Teams Phone runs on computers and mobile; adding physical handsets requires either Teams-certified devices or Direct Routing with compatible hardware), and cost (Teams Phone requires Microsoft 365 licences plus a calling plan add-on, which may be competitive with or more expensive than a standalone VoIP service depending on call volume).

What Happens to VoIP During an NBN Outage

VoIP calls depend on internet connectivity. When the NBN goes down, VoIP calls fail — unless the business has internet failover.

This is one of the most significant practical arguments for a managed business internet plan with seamless failover. When the primary NBN connection fails and failover activates (within approximately one second on a Netluma IT managed plan), VoIP calls survive the transition because:

1. The failover path maintains the same public Static IP address 2. The VoIP provider sees a continuous connection from the same IP 3. Active calls do not drop; the audio may glitch briefly 4. New calls can be placed and received on the failover path

Without failover, an NBN outage means the phone system goes dark — calls to your business number go unanswered or to voicemail. For businesses where phone availability is critical (healthcare practices taking bookings, trades businesses receiving job calls, professional services firms with client calls), this is a significant operational risk.

How VoIP Saves Money for SE Queensland Businesses

The cost comparison between VoIP and a traditional landline/PBX:

Elimination of PSTN line rental. Traditional landlines charge a monthly rental fee per line. A business with four traditional lines pays four line rental fees. VoIP replaces these with a single managed internet connection and a per-user or per-seat VoIP subscription.

Cheaper calls. VoIP calls — particularly national calls — are typically included in the service or priced at a fraction of traditional carrier rates. International call rates are dramatically lower on VoIP.

No PBX hardware to maintain. Traditional phone systems require a physical PBX on-site — hardware that ages, requires maintenance, and eventually fails and needs replacement. Cloud VoIP has no on-site hardware (beyond the phones themselves).

Mobile integration included. Staff can take calls on their mobile through the VoIP app — a feature that traditional systems charge additional per-user fees to enable.

The typical Gold Coast small business with 5–15 staff reduces its phone spend by 30–50% when switching from a traditional system to managed VoIP, while gaining features the old system could not provide.

Netluma IT designs, deploys, and manages VoIP phone systems for SE Queensland businesses. Call 1300 521 162 to discuss what your business needs.