# Interacting with a Public Node

## Overview

The [`RPC`](https://docs.ont.io/ontology-node/interact-with-public-node) interface, [`RESTful`](https://docs.ont.io/ontology-node/interact-with-public-node) interface, and [`WebSocket`](https://docs.ont.io/ontology-node/interact-with-public-node) interface of the Ontology node follow a set of public interface specifications.

By default, the `RESTful` interface listens on `port 20334`, the `WebSocket` interface listens on `port 20335`, the `RPC` interface listens on `port 20336`, and the `EVM` interface listens on `port 10339`.

## Using public nodes

It is inconvenient for developers to run their own nodes. Therefore, the Ontology blockchain provides the `Polaris` test network node and the `Ontology` main network node for developers to use, all supporting `RPC`, `RESTful`, and `WebSocket` calls, and using the default port number.

{% hint style="success" %}
HTTPS is supported in `port 10334` of **Polaris TestNet** node <http://polaris1.ont.io> and **Ontology MainNet** node <http://dappnode1.ont.io>.
{% endhint %}

### Polaris TestNet

The public Ontology polaris test network nodes:

* <http://polaris1.ont.io>
* <http://polaris2.ont.io>
* <http://polaris3.ont.io>
* <http://polaris4.ont.io>
* <http://polaris5.ont.io>

{% hint style="info" %}
If you want to develop on a `Polaris` test network, you can apply for test `ONG` [here](https://developer.ont.io/applyOng).
{% endhint %}

### Ontology MainNet

The public Ontology main network nodes:

* <http://dappnode1.ont.io>
* <http://dappnode2.ont.io>
* <http://dappnode3.ont.io>
* <http://dappnode4.ont.io>

A **private node** can also be set up on the local machine. This can be done by directly compiling and running the [source code](https://github.com/ontio/ontology), but for the convenience of developers, Ontology provides a method to directly download and run a private node. Please follow [this](https://docs.ont.io/ontology-node/interact-with-public-node) link to find the guide.

To find the methods and relevant details on the aforementioned `APIs`, please follow [this](https://docs.ont.io/developer-tools/api) link.

{% hint style="info" %}
For the **Rosetta node API** reference please follow [**this**](https://docs.ont.io/developer-tools/api/rosetta-node-api) link.
{% endhint %}