Building Voice AI Applications: Infrastructure and Telephony Considerations

Building Voice AI Applications: Infrastructure and Telephony Considerations

By Zach Philips-Gary

Voice AI is reshaping how people interact with technology. But building real-time voice applications is fundamentally different from deploying a chatbot or traditional API. These systems demand low-latency infrastructure, persistent audio streams, and session-aware logic, all built to meet user expectations measured in milliseconds, not seconds. That shift has deep implications for how you approach architecture, scaling, and reliability.


Comparing Traditional vs. Real-Time Applications

To understand why voice AI infrastructure is different, it helps to contrast it with the architecture of traditional web applications:


Traditional Web App

Real-Time Voice AI

Request Duration

Milliseconds

Minutes

Interaction Style

Stateless, request/response

Persistent, bidirectional streaming

Resource Pattern

Spiky, short-lived bursts

Steady, continuous usage

Concurrency

High volume, low duration

Lower volume, longer duration

Latency Tolerance

Moderate

Very low

Scalability Focus

Auto-scaling via containers

Session stability and warm pools

This comparison highlights why typical serverless or container-based infrastructure often falls short. In voice AI, warm pools, session handoff, and persistent compute are core architectural needs, not afterthoughts.


The Infrastructure Demands of Voice AI

To deliver a smooth, real-time conversation experience, your backend must consistently respond within 800 milliseconds or less. That timeline includes:

  • Capturing and encoding user audio

  • Sending it to your backend

  • Running transcription and endpointing

  • Passing the transcript to a language model

  • Returning a generated response

  • Running text-to-speech

  • Streaming the result back to the user

Every millisecond counts. That means planning for compute that is always warm, reducing cold starts, co-locating services regionally, and using fast, event-driven pipelines to maintain context across the session.


Handling Latency and Scaling

We’ve seen companies try to build voice experiences on compute services like AWS Lambda or Google Cloud Functions. Those work well for short requests, but fail when the task is maintaining a two-minute call. Your bots need consistent CPU, low jitter, and no restarts during a session.

Voice AI infrastructure must support:

  • Warm containers or virtual machines with pinned memory and CPU

  • Session-aware schedulers that avoid draining or restarting during a call

  • Audio streaming using protocols like WebRTC (Web Real-Time Communication) that support low-latency, resilient communication

  • Real-time monitoring to track latency from speech input to spoken response


The Telephony Layer

Most production-grade voice AI applications need to interface with real-world phone networks or enterprise systems. That means supporting both PSTN (Public Switched Telephone Network) and SIP (Session Initiation Protocol).

Integrations should support:

  • Inbound and outbound calls

  • DTMF (Dual-Tone Multi-Frequency) for handling keypresses

  • Call transfers between systems or agents

  • Echo cancellation and background noise handling

  • Session control APIs that allow the system to direct the call flow

The telephony layer bridges traditional voice networks with cloud infrastructure, and the translation between those two worlds needs to be seamless.


Tooling and Operations

Infrastructure is only one part of the equation. Teams also need tools for:

  • Logging and debugging live sessions

  • Monitoring “time to first word” as a performance metric

  • Scaling capacity based on active conversations

  • Updating systems without disrupting calls

  • Managing routing logic across geographies and telecom providers


Lessons From the Field

We’ve helped companies scale voice AI systems used for customer service, triage, and lead qualification. The biggest lesson is simple. If the infrastructure can’t deliver responses in under a second, or if it stutters during real-time audio, the experience will break.

Voice AI is not just another chatbot. It’s a real-time product that behaves like a human conversation. That sets a high bar, and infrastructure needs to meet it.

Jinka helps teams build and scale infrastructure for voice and language AI products. If you’re working on something in this space and want help making it production-ready, let’s talk.


Voice AI is reshaping how people interact with technology. But building real-time voice applications is fundamentally different from deploying a chatbot or traditional API. These systems demand low-latency infrastructure, persistent audio streams, and session-aware logic, all built to meet user expectations measured in milliseconds, not seconds. That shift has deep implications for how you approach architecture, scaling, and reliability.


Comparing Traditional vs. Real-Time Applications

To understand why voice AI infrastructure is different, it helps to contrast it with the architecture of traditional web applications:


Traditional Web App

Real-Time Voice AI

Request Duration

Milliseconds

Minutes

Interaction Style

Stateless, request/response

Persistent, bidirectional streaming

Resource Pattern

Spiky, short-lived bursts

Steady, continuous usage

Concurrency

High volume, low duration

Lower volume, longer duration

Latency Tolerance

Moderate

Very low

Scalability Focus

Auto-scaling via containers

Session stability and warm pools

This comparison highlights why typical serverless or container-based infrastructure often falls short. In voice AI, warm pools, session handoff, and persistent compute are core architectural needs, not afterthoughts.


The Infrastructure Demands of Voice AI

To deliver a smooth, real-time conversation experience, your backend must consistently respond within 800 milliseconds or less. That timeline includes:

  • Capturing and encoding user audio

  • Sending it to your backend

  • Running transcription and endpointing

  • Passing the transcript to a language model

  • Returning a generated response

  • Running text-to-speech

  • Streaming the result back to the user

Every millisecond counts. That means planning for compute that is always warm, reducing cold starts, co-locating services regionally, and using fast, event-driven pipelines to maintain context across the session.


Handling Latency and Scaling

We’ve seen companies try to build voice experiences on compute services like AWS Lambda or Google Cloud Functions. Those work well for short requests, but fail when the task is maintaining a two-minute call. Your bots need consistent CPU, low jitter, and no restarts during a session.

Voice AI infrastructure must support:

  • Warm containers or virtual machines with pinned memory and CPU

  • Session-aware schedulers that avoid draining or restarting during a call

  • Audio streaming using protocols like WebRTC (Web Real-Time Communication) that support low-latency, resilient communication

  • Real-time monitoring to track latency from speech input to spoken response


The Telephony Layer

Most production-grade voice AI applications need to interface with real-world phone networks or enterprise systems. That means supporting both PSTN (Public Switched Telephone Network) and SIP (Session Initiation Protocol).

Integrations should support:

  • Inbound and outbound calls

  • DTMF (Dual-Tone Multi-Frequency) for handling keypresses

  • Call transfers between systems or agents

  • Echo cancellation and background noise handling

  • Session control APIs that allow the system to direct the call flow

The telephony layer bridges traditional voice networks with cloud infrastructure, and the translation between those two worlds needs to be seamless.


Tooling and Operations

Infrastructure is only one part of the equation. Teams also need tools for:

  • Logging and debugging live sessions

  • Monitoring “time to first word” as a performance metric

  • Scaling capacity based on active conversations

  • Updating systems without disrupting calls

  • Managing routing logic across geographies and telecom providers


Lessons From the Field

We’ve helped companies scale voice AI systems used for customer service, triage, and lead qualification. The biggest lesson is simple. If the infrastructure can’t deliver responses in under a second, or if it stutters during real-time audio, the experience will break.

Voice AI is not just another chatbot. It’s a real-time product that behaves like a human conversation. That sets a high bar, and infrastructure needs to meet it.

Jinka helps teams build and scale infrastructure for voice and language AI products. If you’re working on something in this space and want help making it production-ready, let’s talk.


Jinka


Jinka