js-libp2p/README.md

# js-libp2p-identify

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> libp2p Identify Protocol

## Lead Maintainer

[Jacob Heun](https://github.com/jacobheun)

## Description

Identify is a STUN protocol, used by libp2p-swarm in order to broadcast and learn about the `ip:port` pairs a specific peer is available through and to know when a new stream muxer is established, so a conn can be reused.

## How does it work

Best way to understand the current design is through this issue: https://github.com/libp2p/js-libp2p-swarm/issues/78

### This module uses `pull-streams`

We expose a streaming interface based on `pull-streams`, rather then on the Node.js core streams implementation (aka Node.js streams). `pull-streams` offers us a better mechanism for error handling and flow control guarantees. If you would like to know more about why we did this, see the discussion at this [issue](https://github.com/ipfs/js-ipfs/issues/362).

You can learn more about pull-streams at:

- [The history of Node.js streams, nodebp April 2014](https://www.youtube.com/watch?v=g5ewQEuXjsQ)
- [The history of streams, 2016](http://dominictarr.com/post/145135293917/history-of-streams)
- [pull-streams, the simple streaming primitive](http://dominictarr.com/post/149248845122/pull-streams-pull-streams-are-a-very-simple)
- [pull-streams documentation](https://pull-stream.github.io/)

#### Converting `pull-streams` to Node.js Streams

If you are a Node.js streams user, you can convert a pull-stream to a Node.js stream using the module [`pull-stream-to-stream`](https://github.com/pull-stream/pull-stream-to-stream), giving you an instance of a Node.js stream that is linked to the pull-stream. For example:

```js
const pullToStream = require('pull-stream-to-stream')

const nodeStreamInstance = pullToStream(pullStreamInstance)
// nodeStreamInstance is an instance of a Node.js Stream
```

To learn more about this utility, visit https://pull-stream.github.io/#pull-stream-to-stream.