# Creating a low-latency calling network

DevFeed: [Creating a low-latency calling network](<https://devfeed.tech/articles/creating-a-low-latency-calling-network-1791.md>)

Original publisher: [Read original article](<https://signal.org/blog/low-latency-switching/>)

Published: 2013-01-31T00:00:00Z

Content type: tutorial

Language: en

Sources: [Signal Blog](<https://devfeed.tech/sources/signal-blog.md>)

Topics: [App](<https://devfeed.tech/topics/app.md>), [Cryptography](<https://devfeed.tech/topics/cryptography.md>), [Security, Privacy and Abuse Prevention](<https://devfeed.tech/topics/security-privacy-and-abuse-prevention.md>)

Tags: [availability](<https://devfeed.tech/tags/availability.md>), [communication](<https://devfeed.tech/tags/communication.md>), [cryptographic](<https://devfeed.tech/tags/cryptographic.md>), [infrastructure](<https://devfeed.tech/tags/infrastructure.md>), [low-latency](<https://devfeed.tech/tags/low-latency.md>), [mobile](<https://devfeed.tech/tags/mobile.md>), [networks](<https://devfeed.tech/tags/networks.md>), [push-notification](<https://devfeed.tech/tags/push-notification.md>), [server](<https://devfeed.tech/tags/server.md>), [voice](<https://devfeed.tech/tags/voice.md>)

## AI overview

The article explains RedPhone's network strategy for high-quality, low-latency, highly available mobile voice calls. It covers a custom signaling switch, push notifications, and TURN-style packet relaying to handle restrictive mobile NATs and reduce regional latency.

## Source excerpt

RedPhone is our mobile app for end-to-end encrypted voice calls. When we talk about RedPhone, we tend to emphasize the cryptography, and how using it can help keep your communications safe. What we don't talk about as much is the VoIP application underneath all of that, which it turns out was actually the hard part. When we were developing RedPhone, we discovered that the cryptographic aspects of it were relatively straightforward. What we didn't anticipate was how difficult the mechanics of delivering high-quality, low-latency, and highly available voice communication would be. This describes the basic strategy we developed for the network side of low-latency and highly available calls. Read more...