VoLTE Vs VoIP

What Is VoLTE?

Voice over LTE (VoLTE) enables voice calls over 4G LTE networks rather than traditional 2G or 3G networks. By using LTE, VoLTE supports high-speed data alongside voice services. This results in clearer call quality, faster call setup, and simultaneous access to voice and data on compatible devices. It is particularly useful in areas with strong LTE coverage, allowing users to experience uninterrupted connectivity for both voice and internet activities.

VoLTE integrates with IP multimedia subsystem (IMS), a framework that supports communication services like video calling and conferencing. Additionally, VoLTE works well in modern mobile ecosystems, offering improved spectral efficiency. However, it requires both compatible devices and network support, which can be a limitation in certain regions.

VoLTE vs Other VoIP Networks: Similarities and 5 Key Differences

What Is VoIP?

Voice over internet protocol (VoIP) enables voice communication via the internet. Instead of traditional voice networks, VoIP transmits voice data as digital packets over IP networks. This makes it a cost-effective alternative, particularly for international calls or enterprises aiming to integrate voice communication with other data systems. VoIP is primarily used in applications like Zoom or Microsoft Teams.

VoIP can function on various devices, including computers, smartphones, and specialized IP phones, as long as they are connected to the internet. However, the quality of VoIP calls often depends on the speed and stability of the internet connection. While it offers flexibility and cost savings, VoIP’s reliance on internet connectivity can result in degraded call quality or dropped calls in areas with poor network performance.

There are several types of VoIP networks, with VoLTE being one of them:

Over-the-Top (OTT) VoIP: Runs on public internet connections without integration into the carrier’s network. Examples include WhatsApp, Skype, and Viber, which use proprietary protocols over general broadband or mobile data networks.

Managed VoIP: Provided by telecom operators or ISPs who manage and prioritize VoIP traffic within their network. This approach helps maintain call quality and reduces issues like jitter and packet loss.

Enterprise VoIP (Unified Communications): Typically hosted on private IP networks with integrated collaboration features like video conferencing, instant messaging, and screen sharing. Examples include Cisco Webex and Microsoft Teams.

VoLTE (Voice over LTE): A carrier-based VoIP implementation on LTE networks, supporting high-definition voice and seamless mobility with QoS guarantees.

VoLTE vs. VoIP: The Similarities

Both VoLTE and other VoIP networks use packet-switched networks to transmit voice data, moving away from traditional circuit-switched telephony. This allows for more efficient use of network resources and supports features like HD voice and video calls. They both convert voice into data packets, transmit them over IP-based networks, and reassemble them at the receiving end.

Both technologies also support integration with digital communication platforms. VoLTE uses IMS to handle services such as messaging, video calling, and conferencing. Similarly, other types of VoIP networks can integrate with unified communication systems and software platforms, enabling voice, messaging, and collaboration features within a single interface.

Another similarity is the reliance on end-to-end IP connectivity. Whether through LTE networks or general internet access, both VoLTE and VoIP require compatible infrastructure and sufficient bandwidth to ensure high call quality.

VoLTE vs. Non-Cellular VoIP: The Key Differences

1. Network Type

VoLTE (Voice over LTE) relies exclusively on the LTE cellular network infrastructure. LTE networks are designed with low latency and high data throughput, enabling the delivery of real-time services like voice and video. 

Within LTE, voice traffic is transmitted using a dedicated bearer, which ensures isolation from regular data streams and provides prioritized handling. This network architecture allows VoLTE to support stringent QoS parameters such as guaranteed bit rate, packet delay budget, and packet error loss rate.

VoIP (Voice over internet protocol) operates over any IP-based network, including Wi-Fi, broadband, Ethernet, and mobile data (3G, 4G, or 5G). 

Because VoIP uses the public internet, there is no built-in prioritization of voice packets unless the network administrator configures traffic shaping or QoS at the local network level. As a result, VoIP is more vulnerable to issues like jitter, latency, and packet loss, especially in unmanaged or heavily loaded networks.

2. Device Support

VoLTE support is limited to devices that meet narrow hardware and software criteria. These include support for LTE radios, integrated IMS clients, and firmware certified by mobile carriers. 

VoLTE functionality is often disabled by default on unlocked or international phones unless explicitly supported by the network. Firmware updates may be necessary to enable VoLTE on certain devices.

VoIP is highly versatile in terms of device compatibility. It can operate on virtually any device that has a microphone, speaker, and internet connection. This includes smartphones, laptops, tablets, desktop computers, and dedicated IP desk phones. 

Traditional landline phones can also connect via VoIP using analog telephone adapters (ATAs), which convert analog signals into digital packets. VoIP applications are available across major operating systems, and many platforms allow cross-device syncing.

3. Mobility

VoLTE is inherently mobile-first. It supports continuous service as users move between cell towers, maintaining session continuity and quality. 

Features like SRVCC (Single Radio Voice Call Continuity) allow seamless handover from LTE to 3G or 2G networks when users move out of LTE coverage areas. This ensures ongoing calls do not drop and audio quality remains consistent.

VoIP mobility is application-based rather than network-integrated. Calls may drop or degrade when switching between networks (e.g., moving from Wi-Fi to cellular data). Maintaining call continuity across networks often requires solutions like SIP session management or mobile-optimized transport protocols such as ICE/STUN/TURN for NAT traversal.

4. Call Quality

VoLTE consistently delivers high-definition (HD) voice quality due to its use of wideband codecs like AMR-WB (Adaptive Multi-Rate Wideband). These codecs cover a broader audio frequency range (typically 50 Hz to 7 kHz), resulting in clearer and more natural-sounding voice. The dedicated LTE bearer ensures minimal interference from other data streams, supporting low latency (around 50ms round-trip) and high reliability.

VoIP also supports HD voice, but its performance is highly dependent on external factors. Many VoIP systems use codecs like G.711, G.722, or Opus, which vary in bandwidth consumption and error tolerance. In high-quality networks, VoIP can match or exceed VoLTE audio fidelity. However, without QoS or sufficient bandwidth, issues such as echo, delay, and dropped audio frames become common.

5. Call Setup Time

VoLTE benefits from fast call setup times, generally between 1 to 2 seconds. This speed comes from its persistent connection to the LTE network and pre-established signaling paths via the IMS core. Call signaling messages are processed rapidly within the mobile network, allowing instant transitions from dialing to call ringing.

VoIP setup times are longer and less predictable. Depending on the SIP infrastructure, NAT traversal mechanisms, and firewall configurations, call initiation may involve multiple handshake steps and address resolution processes. For example, in a residential setup with a consumer router, SIP messages may be delayed or blocked without port forwarding or STUN server configuration.

6. Integration

VoLTE offers deep integration with cellular network features. This includes support for emergency services (e.g., 911), carrier voicemail, SMS messaging, and call continuity. Because VoLTE uses the same identity management as other carrier services (typically the SIM card), users experience a unified communication system that works out of the box with native apps and interfaces.

VoIP provides flexible but more fragmented integration. It is highly customizable, supporting APIs, programmable call flows, and integration with software like CRMs, helpdesk platforms, and collaboration suites (e.g., Slack, Salesforce, Zoom). However, these integrations require configuration and are dependent on the service provider’s ecosystem.

7. Use Cases

VoLTE is tailored for mobile voice communication in consumer markets. It is especially relevant as carriers phase out 2G and 3G networks in favor of LTE and 5G, where VoLTE is essential for voice functionality. It supports casual personal communication, integrated mobile services, and use in geographically distributed areas with cellular coverage but no wired internet.

VoIP works best in business and global communication contexts. It is widely adopted in call centers, remote work environments, multinational teams, and software-driven workflows. Its lower cost per call, especially for international calls, and ability to integrate with digital tools make it the preferred option for enterprises. VoIP also powers a range of OTT services such as WhatsApp, Google Meet, and Microsoft Teams, enabling voice and video communication across the internet without relying on carrier infrastructure.

Is VoLTE Right for You?

VoLTE is ideal if your organization depends on reliable mobile communication, especially in areas with strong LTE coverage and where maintaining call quality is essential. It suits businesses that require seamless voice and data usage on the same device, such as logistics, field services, or customer support teams operating remotely. It also benefits organizations aiming to future-proof their mobile communication as 2G and 3G networks phase out.

-Key considerations for choosing VoLTE:

• -Coverage and infrastructure: Choose VoLTE if your workforce relies heavily on mobile networks and operates in regions with robust LTE support. Opt for non-cellular VoIP if broadband connectivity is stable and widely available.Device and network control: Use managed VoIP or SIP trunking if your IT team needs tight control over network settings, device compatibility, and integration with internal systems like CRMs or call analytics tools.

  Mobility vs. flexibility: VoLTE provides better mobility and integration with native mobile features. Other types of VoIP networks offer more flexibility, especially across different device types and locations.

  Cost efficiency: For international or high-volume calling needs, VoIP—especially OTT apps—can be more economical due to lower per-minute rates and broader service options.

  Integration requirements: Select enterprise VoIP or SIP trunking if you need extensive integration with business software. VoLTE is more limited in this aspect and relies on carrier-level features.

  Service reliability: If call quality and low latency are critical, and you’re operating within a mobile-first environment, VoLTE is preferable due to its QoS guarantees. VoIP’s performance can change with internet quality.

VoLTE IoT Connectivity with floLIVE

floLIVE offers a robust suite of voice services for IoT devices, supporting both traditional circuit-switched voice and advanced Voice over LTE (VoLTE) capabilities. Purpose-built to meet the rising demand for real-time voice communication and high-speed data in IoT deployments, floLIVE’s VoLTE solution is deployed on its own core network and integrated with an in-house IMS (IP Multimedia Subsystem).

The IMS connects to the Packet Data Network (PDN) Gateway via the SGi interface and is configured to support both Mobile Originating (MO) and Mobile Terminating (MT) voice services through seamless integration with termination partners and MSISDN provisioning.

The solution is tightly integrated with floLIVE’s Connectivity Management Platform (CMP), enabling streamlined management of voice services, billing, call preferences, and analytics from a single interface.

Here are the main points that differentiate floLIVE from other solutions:

1. Full ownership of the cellular ecosystem: unlike competitors that depend on third-party components, floLIVE has developed and operates its entire cellular stack- including the core network, IMS, and CMP. This vertical integration ensures unmatched flexibility, control, and the ability to rapidly adapt to specific customer needs.

2. Integrated Multi-IMSI Technology: floLIVE’s VoLTE solution is enhanced by its proprietary multi-IMSI capability, allowing devices to automatically switch between networks—even across borders—without service interruption. This is crucial for mission-critical use cases such as connected healthcare, automotive (eCall), and emergency response systems.

3. Geo-Redundant and Scalable Deployment: floLIVE’s globally distributed IMS architecture provides geo-redundancy and high availability. The system is designed to scale effortlessly as customer demands grow, ensuring consistent quality without service degradation.

4. Unified Management via CMP: VoLTE capabilities are fully integrated into floLIVE’s CMP, offering customers a centralized interface to manage all aspects of IoT connectivity—including data, voice, SIM lifecycle, alerts, and billing—greatly simplifying operational complexity.

5. End-to-End Security and Quality of Service: By running IMS on its proprietary core infrastructure, floLIVE ensures robust security and tightly controlled Quality of Service (QoS) parameters. This guarantees reliable, high-quality voice communication, even in latency-sensitive environments.

6. Regulatory Compliance and eCall Support:

floLIVE’s VoLTE solution is designed with regulatory compliance in mind, particularly for emergency services like eCall.

Europe (NG112 Compliant): floLIVE’s eCall implementation aligns with mandatory EU regulations for all new vehicles (since 2018), leveraging IMS and SIP signaling to support the Next Generation 112 (NG112) standard.
United States (NG911 Compatible): While eCall is not mandatory in the U.S., floLIVE ensures compliance with NENA standards and supports emergency call routing over NG911 frameworks.

7. Key eCall Features:

IMS-Based SIP Signaling: Enables accurate call setup and flow control.
Minimum Set of Data (MSD): Transmits vital information (e.g., crash data, location) in parallel with the voice call.

Location-Based PSAP Routing: Calls are intelligently routed to the nearest Public Safety Answering Point (PSAP) using NPLI and other geolocation methods.

Cross-Border Interoperability: Ensures MSD delivery and voice call integrity across regulatory regions, aligned with ETSI guidelines in Europe.

Learn more about floLIVE