What is VoIP and How Does it Work?
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VoIP systems convert analog input (your voice) into digital data for transmission over the internet. Adoption of VoIP telephony is increasing as more businesses move away from traditional landline systems, fueling the digital transformation of many organizations across industries.
This page provides a quick overview of VoIP technology, the business benefits of making the switch, the setup requirements you’ll need to meet and additional factors to consider when shopping for a VoIP provider.
What is Voice Over Internet Protocol (VoIP)?
VoIP, meaning Voice over Internet Protocol, is a technology that converts analog voice signals into digital data packets that can be securely transmitted over the internet. By definition, voice over IP replaces traditional copper wire phone lines and circuit-switched networks with internet-based calling.
Landline use has been declining due to the widespread adoption of cell phones by the general public. This trend has also impacted the business world, and VoIP systems have expanded to fill the gaps left by the Plain Old Telephone System (POTS) in favor of telephony that uses the high-speed internet connection already in place. VoIP is sometimes referred to as IP telephony, internet telephony, broadband telephony or SIP trunking.
How VoIP Works
The basic process of placing a VoIP call looks something like this:
- Voice is captured as analog signals by a microphone (on a VoIP handset, or softphone app on your tablet, PC or mobile phone)
- An Analog-to-Digital Converter (ADC) converts that signal into digital data
- Voice codecs compress the data into packets
- Packets are transmitted via internet protocols (RTP/UDP)
- Packets are reassembled at their destination
- Digital-to-Analog Converter (DAC) converts the data back to sound waves
And all of that takes place in milliseconds, leading to a seamless experience that feels just like a call on a traditional landline. Some of the technologies involved in this process are borrowed from other disciplines like audio recording and playback, while others are unique to VoIP implementations:
- Codec: A portmanteau of “coder/decoder,” a codec is responsible for turning analog voice sound into digital data that can be transmitted across the internet.
- SIP: Session Initiation Protocol (SIP) sets up your call, establishes routing and manages the session or call from start to finish.
- Endpoints: For VoIP calling, an endpoint can be a dedicated VoIP handset, headset or a software-based phone app, called a softphone, that can be installed on any device, like a PC, tablet or smartphone.
VoIP vs Landlines
| Feature | VoIP | Landline |
|---|---|---|
| Cost structure | Significant cost savings thanks to no long-distance fees and minimal hardware costs | High setup costs, long-distance charges and PBX equipment installation costs |
| Flexibility | Location-independent, calls can be made from anywhere with an internet connection | Fixed to the physical location where the PBX and infrastructure are installed |
| Scalability | Quick and easy to add/remove lines and make configuration changes from a central dashboard | Hardware limits expansion, and complicated PBX software is needed to make configuration changes |
| Feature set | Advanced features often included (call forwarding, auto attendant, voicemail-to-email, etc.) | Basic calling features, limited advanced features may be available with additional fees |
| Mobility | Mobile apps enable streamlined hybrid and remote work scenarios | Users are tied to their desks by physical phones and wiring infrastructure |
| Call Quality | HD voice quality available, bandwidth dependent | Consistent but limited to standard audio quality |
| Reliability | Internet-dependent, but modern systems can offer high-uptime guarantees | Vulnerable to physical line damage that can lead to significant downtime in certain scenarios |
Further key advantages of VoIP:
- Elimination of separate voice and data networks reduces the complexity of the necessary infrastructure.
- Advanced feature sets like conference calling and collaboration tools are included, improving team productivity regardless of where teams are located.
- Remote work compatibility is essential for modern business operations to run smoothly.
Benefits of Using VoIP
Cost-Effectiveness and Scalability
Businesses typically achieve substantial savings on their phone bills after making the switch to VoIP, thanks to several factors:
- Elimination of long-distance charges for both domestic and international calls
- Reduced infrastructure costs by combining voice and data networks
- Lower maintenance and overhead expenses compared to a traditional private branch exchange (PBX) system
These savings are multiplied when you account for the easy expansion and scalability of VoIP:
- No need for on-site PBX hardware
- Easy line addition without any needed changes to physical infrastructure
- Flexible pricing models that grow with your business needs
- Workforce reallocation as automated features reduce administrative overhead
Enhanced Features and Flexibility
Beyond the cost savings and easy scalability, VoIP solutions offer additional benefits, such as advanced feature sets and workforce flexibility.
- Features like call forwarding, voicemail-to-email transcription, auto-attendant with customizable greetings and routing options and CRM integration all enhance the user and customer experience.
- Video calling and conferencing capabilities are baked in
- Call analytics and reporting enable robust business intelligence
- Mobile apps allow complete portability; one number reaches you anywhere in the world
- Enhanced productivity and support for hybrid work models and distributed teams
Global Accessibility and Integration
What Do You Need to Set Up VoIP?
- High-speed broadband internet: VoIP functionality requires a reliable connection with adequate bandwidth for concurrent calls and other data-based business operations. Wired Ethernet is preferred over WiFi for handsets to reduce latency and increase connection stability.
- VoIP service provider: When comparing providers, look for high uptime guarantees, transparent pricing models and comprehensive customer support across channels.
- VoIP hardware considerations: IP phones for plug-and-play deployments at the office, softphone apps for laptops and mobile devices cut costs and enable hybrid work and Analog Terminal Adapters (ATAs) enable integration of existing analog phone hardware.
- Network infrastructure considerations: Enterprise-grade routers with quality of service (QoS) functionality for optimal performance, network security measures, firewall configurations that take into account the additional network traffic and a solid backup internet connection for redundancy will all help ensure business continuity in case of disruption.
- Additional business requirements: SIP trunking for enterprise-level connections and additional scalability, flexible licensing models accommodating business growth and integration with existing tech workflows, keeping productivity uninterrupted.
VoIP in Business: Why It Matters
VoIP Phones and Unified Communications
VoIP solutions provide a unified communication (UC) platform that integrates voice, video and messaging. This streamlines workflows, reduces application switching and enables real-time collaboration with additional features like file sharing and text messaging.
Customer relationship management (CRM) platform integration can display customer information before initiating a call, so your customer service staff are better prepared to assist the caller. Call recording and monitoring features elevate quality assurance and advanced call routing ensures customers reach the right person the first time, automatically.
Role of VoIP in Digital Transformation
The shift from POTS to VoIP supports organizations’ digital-first strategies by enabling collaboration and hybrid workforce productivity. Migrating to cloud-based solutions brings further benefits like the elimination of physical phone infrastructure and the maintenance it requires. Cloud-based tools are inherently more scalable to adapt to changing business needs, and real-time analytics enable data-driven decision-making.
Further competitive advantages include enhanced mobility and accessibility, global connectivity, AI automation integration and improved collaboration tools for dispersed teams.
How to Choose a VoIP Provider
Evaluating a VoIP provider entails examining several sets of factors to ensure they align with your business needs:
Reliability and infrastructure
- High uptime guarantees with robust SLAs
- Multiple global data centers for redundancy and failover capabilities
- Network quality and geographic coverage that match your requirements
Feature set evaluation
- Core vs. advanced features assessment based on your needs
- Scalability options that accommodate your projected growth
- Integration capabilities with your existing line-of-business applications
Support and service quality
- Comprehensive customer support across channels
- Technical expertise and fast response times for issue resolution
- Implementation assistance and training
Security and compliance
- Strong encryption and security protocols to keep your data safe
- Regular security updates and proactive monitoring
- Industry-specific regulatory compliance
Business-specific considerations
- Transparent pricing structure with no hidden fees
- Mobile compatibility and apps for hybrid and remote workforces
- User-friendly management console or dashboard
Stay Connected with GTT Voice Solutions
GTT delivers enterprise-grade VoIP solutions for businesses that demand reliability, global reach, advanced features and 24/7 support from telephony experts. Our comprehensive voice solutions integrate seamlessly with your existing infrastructure, providing the scalability and performance growing organizations need. GTT offers flexible options like Cloud Phone Direct for simplified deployments, Zoom Phone with GTT SIP Trunking for seamless collaboration and robust SIP Trunking for enterprise-level scalability.
Whether you’re migrating from a traditional phone system or upgrading your existing VoIP infrastructure, take the next step and talk to our experts in all things VoIP for personalized consultation and implementation guidance.
Learn more about how GTT can help support your business collaboration, mobility and growth
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