---
source_url: https://www.pubnub.com/docs/general/setup/data-transport
title: Data transport & protocols
updated_at: 2026-06-17T11:38:12.956Z
---

> Documentation Index
> For a curated overview of PubNub documentation, see: https://www.pubnub.com/docs/llms.txt
> For the full list of all documentation pages, see: https://www.pubnub.com/docs/llms-full.txt


# Data transport & protocols

PubNub is protocol agnostic. It runs on the global PubNub Data Stream Network. It chooses the best protocol for the user’s network, so your app stays connected.

As networks change (cell tower switching, double NAT, antivirus, and proxies), PubNub’s SDKs switch protocols so that connections stay stable, fast, and use very little power.

Over time, PubNub has used multiple protocols:

* WebSockets
* COMET
* BOSH
* SPDY
* [Long polling](https://www.pubnub.com/guides/long-polling/)

Transport is a non-issue because PubNub picks the most efficient protocol for each SDK and runtime. Client and server SDKs update to new standards over time. They shield you from protocol details so you can focus on features.

PubNub ensures performance and reliability. Think of it as a scalable, secure, and fast messaging backbone that removes transport complexity.

## HTTP/2

PubNub supports HTTP/2 on select origins. Clients connecting to supported origins negotiate HTTP/2 automatically. HTTP/1.1 remains fully supported for all clients and endpoints. The goal is the same: to work in any network, use minimal bandwidth, and save power, especially on mobile.

:::note Contact support
To request HTTP/2 support for a custom origin, [contact PubNub Support](https://support.pubnub.com/).
:::

## Terms in this document

* **PubNub** - PubNub is a real-time messaging platform that provides APIs and SDKs for building scalable applications. It handles the complex infrastructure of real-time communication, including: Message delivery and persistence, Presence detection, Access control, Push notifications, File sharing, Serverless processing with Functions and Events & Actions, Analytics and monitoring with BizOps Workspace, AI-powered insights with Illuminate.